Novel Procoagulant Proteins

This invention relates to a novel series of proteins which exhibit procoagulant properties. These proteins have marked structural differences from human factor VIII:C, but have similar procoagulant activity.

Factor VIII:C is the blood plasma protein that is defective or absent in Hemophilia A disease. This disease is a hereditary bleeding disorder affecting approximately one in 20,000 males. The structure of factor VIII:C is described in U.S. Patent Applications Ser. Nos. 546,650 filed Oct. 28, 1983 and 644,036 filed Aug. 24, 1984, which are incorporated herein by reference and in Nature. 312:306, 307, 326 and 342.

One of the problems presently encountered with the use of human factor VIII:C for treatment of hemophilia arises from its antigenicity. A significant percentage of hemophiliacs have developed an immune reaction to the factor VIII:C used for their treatment. Non-hemophiliacs can also develop or acquire hemophilia when their immune systems become sensitized to factor VIII:C and produce circulating antibodies or "inhibitors" to factor VIII:C. In either case, the effect is the neutralization of whatever factor VIII:C is present in the patient, making treatment very difficult. Until now, the method of choice for treating hemophiliacs with this problem has been to administer, in cases of severe bleeding episodes, non-human factor VIII:C, such as treated porcine factor VIII:C. See Kernoff et al., Blood 63:31 (1984). However, the antibodies which neutralize the clotting ability of human factor VIII:C will react to a varying extent with factor VIII:C of other species, and the porcine protein is itself antigenic, thus both the short-term and long-term effectiveness of such treatment will vary.

Additionally, patients frequently display adverse reactions to infusion with the porcine factor VIII:C. The use of porcine factor VIII:C in spite of the risks has been justified because of the lack of reliably effective alternatives. Kernoff, supra at 38. The present invention provides an alternative to the administration of porcine factor VIII:C.

This invention provides for proteins which have procoagulant activity similar to that of factor VIII:C and also have substantially lower molecular weight. These proteins are schematically depicted by formula (1) as follows:

wherein A represents a polypeptide sequence substantially duplicative of the sequence Ala-20 through Arg-759; B represents a polypeptide sequence substantially duplicative of the sequence Ser-1709 through the C-terminal Tyr-2351; and X represents a polypeptide sequence of up to 949 amino acids substantially duplicative of sequences of amino acids within the sequence Ser-760 through Arg-1708. The amino terminus of region X is covalently bonded through a peptide bond (designated "-" in formula 1) to the carboxy terminus of A. The carboxy terminus of region X is likewise bonded to the amino terminus of B. Numbering of amino acids throughout this disclosure is with reference to the numbering of amino acids in Table 1 in which the first amino acid, Met, of the leader sequence is assigned Number 1. Protein domain X may comprise a continuous but shorter sequence selected from the region Ser-760 through Arg-1708. Alternatively X may comprise two or more amino acid sequences selected from that region which are covalently bonded by a peptide bond (maintaining an ascending numerical order of amino acids). 5' GAATTCCCCACTGGGTAAGTTCCTTAAAGCTCTGGAAAGAAATTCCGACTTTTCATTAAATCAGAAATT TTACTTTTTTCCCCTCCTGGGACCTAAAGATATTTTAGAGAAGAATTAACCTTTTGCTTCTCCAGTTGAACAT TTCTAGCAATAAGTC MET Gln Ile Glu Leu Ser Thr Cys Phe Phe Leu Cys Leu Leu Arg Phe Cys Phe 18 ATG CAA ATA CAG CTC TCC ACC TGC TTC TTT CTG TGC CTT TTG CCA TTC TCC TTT Ser Ala Thr Arg Arg Tyr Tyr Leu Gly Ala Val Glu Leu Ser Trp Asp Tyr MET 36 ACT CCC ACC AGA AGA TAC TAC CTG GGT CCA CTG GAA CTC TCA TGC GAC TAT ATC Gln Ser Asp Leu Gly Glu Leu Pro Val Asp Ala Arg Phe Pro Pro Arg Val Pro 54 CAA AGT GAT CTC GGT CAG CTG CCT GTG CAC GCA AGA TTT CCT CCT AGA CTG CCA Lys Ser Phe Pro Phe Asn Thr Ser Val Val Tyr Lys Lys Thr Leu Phe Val Glu 72 AAA TCT TTT CCA TTC AAC ACC TCA CTC GTG TAC AAA AAG ACT CTG TTT GTA GAA Phe Thr Val His Leu Phe Asn Ile Ala Lys Pro Arg Pro Pro Trp MET Gly Leu 90 TTC ACG GTT CAC CTT TTC AAC ATC CCT AAG CCA ACC CCA CCC TGG ATG CCT CTG Leu Gly Pro Thr Ile Gln Ala Glu Val Tyr Asp Thr Val Val Ile Thr Leu Lys 108 CTA GGT CCT ACC ATC CAG CCT GAG GTT TAT CAT ACA GTG GTC ATT ACA CTT AAG Asn MET Ala Ser His Pro Val Ser Leu His Ala Val Gly Val Ser Tyr Trp Lys 126 AAC ATG GCT TCC CAT CCT GTC ACT CTT CAT GCT GTT CGT GTA TCC TAC TGG AAA Ala Ser Glu Gly Ala Glu Tyr Asp Asp Gln Thr Ser Gln Arg Glu Lys Glu Asp 144 GCT TCT CAG CCA CCT CAA TAT CAT CAT CAC ACC ACT CAA AGG CAG AAA GAA CAT Asp Lys Val Phe Pro Gly Gly Ser His Thr Tyr Val Trp Gln Val Leu Lys Glu 162 GAT AAA GTC TTC CCT CCT GGA ACC CAT ACA TAT CTC TCC CAG CTC CTG AAA GAG Asn Gly Pro MET Ala Ser Asp Pro Leu cys Leu Thr Tyr Ser Tyr Leu Ser His 180 AAT GGT CCA ATG GCC TCT CAC CCA CTG TCC CTT ACC TAC TCA TAT CTT TCT CAT Val Asp Leu Val Lys Asp Leu Asn Ser Gly Leu Ile Gly Ala Leu Leu Val Cys 198 GTG GAC CTG CTA AAA GAC TTG AAT TCA CGC CTC ATT GGA CCC CTA CTA CTA TGT Arg Glu Gly Ser Leu Ala Lys Glu Lys Thr Gln Thr Leu His Lys Phe Ile Leu 216 AGA CAA GGG AGT CTG GCC AAG CAA AAG ACA CAG ACC TTG CAC AAA TTT ATA CTA Leu Phe Ala Val Phe Asp Glu Gly Lys Ser Trp His Ser Glu Thr Lys Asn Ser 234 CTT TTT GCT GTA TTT CAT GAA GGG AAA ACT TGC CAC TCA GAA ACA AAG AAC TCC Leu MET Gln Asp Arg Asp Ala Ala Ser Ala Arg Ala Trp Pro Lys MET His Thr 252 TTG ATG CAG CAT AGG CAT GCT CCA TCT CCT CCG GCC TGG CCT AAA ATG CAC ACA Val Asn Gly Tyr Val Asn Arg Ser Leu Pro Gly Leu Ile Gly Cys His Arg Lys 270 GTC AAT CGT TAT GTA AAC AGG TCT CTG CCA CCT CTG ATT CCA TCC CAC ACG AAA Ser Val Tyr Trp His Val Ile Gly MET Gly Thr Thr Pro Glu Val His Ser Ile 288 TCA CTC TAT TGG CAT CTG ATT GCA ATG GGC ACC ACT CCT GAA GTC CAC TCA ATA Phe Lue Glu Gly His Thr Phe leu Val Arg Asn His Arg Gln Ala Ser Leu Glu 306 TTC CTC CAA CCT CAC ACA TTT CTT CTC ACC AAC CAT CCC CAC CCG TCC TTG CAA Ile Ser Pro Ile Thr Phe Leu Thr Ala Gln Thr Leu Leu MET Asp Leu Gly Gln 324 ATC TCG CCA ATA ACT TTC CTT ACT CCT CAA ACA CTC TTG ATG CAC CTT GGA CAG Phe Leu Leu Phe Cys His Ile Ser Ser His Gln His Asp Gly MET Glu Ala Tyr 342 TTT CTA CTG TTT TCT CAT ATC TCT TCC CAC CAA CAT GAT GGC ATG CAA GCT TAT Val Lys Val Asp Ser Cys Pro Glu Glu Pro Gln Leu Arg MET Lys Asn Asn Glu 360 GTC AAA GTA GAC AGC TGT CCA GAG GAA CCC CAA CTA CGA ATG AAA AAT AAT GAA Glu Ala Glu Asp Tyr Asp Asp Asp Leu Thr Asp Ser Glu MET Asp Val Val Arg 378 GAA GCG GAA GAC TAT GAT GAT GAT CTT ACT CAT TCT GAA ATG GAT CTG GTC AGG Phe Asp Asp Asp Asn Ser Pro Ser Phe Ile Gln Ile Arg Ser Val Ala Lys Lys 396 TTT GAT GAT GAC AAC TCT CCT TCC TTT ATC CAA ATT CCC TCA GTT GCC AAG AAG His Pro Lys Thr Trp Val His Tyr Ile Aln Ala Glu Glu Glu Asp Trp Asp Tyr 414 CAT CCT AAA ACT TGG GTA CAT TAC ATT GCT GCT GAA GAG GAG GAC TGG GAC TAT Ala Pro Leu Val Leu Ala Pro Asp Asp Arg Ser Tyr Lys Ser Gln Tyr Leu Asn 432 GCT CCC TTA GTC CTC GCC CCC CAT GAC AGA AGT TAT AAA AGT CAA TAT TTG AAC Asn Gly Pro Gln Arg Ile Gly Arg Lyn Tyr Lys Lys Val Arg Phe MET Ala Tyr 450 AAT GCC CCT CAG CGG ATT GGT AGG AAC TAC AAA AAA CTC CGA TTT ATG CCA TAC Thr Asp Glu Thr Phe Lys Thr Arg Glu Ala Ile Gln His Glu Ser Gly Ile Leu 468 ACA CAT GAA ACC TTT AAG ACT CGT GAA CCT ATT CAG CAT GAA TCA CCA ATC TTG Gly Pro Leu Leu Tyr Gly Glu Val Gly Asp Thr Leu Leu Ile Ile Phe Lys Asn 486 GGA CCT TTA CTT TAT GGG GAA GTT CCA GAC ACA CTG TTC ATT ATA TTT AAG AAT Gln Ala Ser Arg Pro Tyr Asn Ile Tyr Pro His Gly Ile Thr Asp Val Arg Pro 504 CAA GCA AGC ACA CCA TAT AAC ATC TAC CCT CAC CGA ATC ACT CAT GTC CGT CCT Leu Tyr Ser Arg Arg Leu Pro Lys Gly Val Lys His Leu Lys Asp Phe Pro Ile 522 TTG TAT TCA AGG AGA TTA CCA AAA GGT GTA AAA CAT TTG AAG GAT TTT CCA ATT Leu Pro Gly Glu Ile Phe Lys Tyr Lys Trp Thr Val Thr Val Glu Asp Gly Pro 540 CTG CCA GGA GAA ATA TTC AAA TAT AAA TGG ACA GTG ACT GTA CAA CAT GGG CCA Thr Lys Ser Asp Pro Arg Cys Leu Thr Arg Tyr Tyr Ser Ser Phe Val Asn MET 558 ACT AAA TCA GAT CCT CGG TGC CTG ACC CGC TAT TAC TCT ACT TTC GTT AAT ATG Glu Arg Asp Leu Ala Ser Gly Leu Ile Gly Pro Leu Leu Ile Cys Tyr Lys Glu 576 GAG AGA GAT CTA GCT TCA GGA CTC ATT CGC CCT CTC CTC ATC TGC TAC AAA GAA Ser Val Asp Gln Arg Gly Asn Gln Ile MET Ser Asp Lys Arg Asn Val Ile Leu 594 TCT GTA GAT CAA AGA GGA AAC CAG ATA ATG TCA GAC AAG AGG AAT GTC ATG CTG Phe Ser Vnl Phe Asp Glu Asn Arg Ser Trp Tyr Leu Thr Glu Asp Ile Gln Arg 612 TTT TCT GTA TTT CAT CAG AAC CGA AGC TCG TAC CTC ACA CAG AAT ATA CAA CGC Phe Leu Pro Asn Pro Ala Gly Val Gln Leu Glu Asp Pro Glu Phe Gln Ala Ser 630 TTT CTC CCC AAT CCA CCT CGA GTG CAG CTT CAG CAT CCA GAG TTC CAA GCC TCC Asn Ile MET His Ser Ile Asn Gly Tyr Val Phe Asp Ser Leu Gln Leu Ser Val 648 AAC ATC ATG CAC ACC ATC AAT GGC TAT CTT TTT CAT ACT TTG CAG TTG TCA GTT Cys Leu His Glu Val Ala Tyr Trp Tyr Ile Leu Ser Ile Gly Ala Gln Thr Asp 666 TGT TTG CAT CAG CTG CCA TAC TGG TAC ATT CTA ACC ATT GGA GCA CAG ACT CAC Phe Leu Ser Val Phe Phe Ser Gly Tyr Thr Phe Lys His Lys MET Val Tyr Glu 684 TTC CTT TCT GTC TTC TTC TCT GGA TAT ACC TTC AAA CAC AAA ATG GTC TAT CAA Asp Thr Leu Thr Leu Phe Pro Phe Ser Gly Glu Thr Val Phe MET Ser MET Glu 702 GAC ACA CTC ACC CTA TTC CCA TTC TCA GGA CAA ACT GTC TTC ATG TCG ATG GAA Asn Pro Gly Leu Trp Ile Leu Gly Cys His Asn Ser Asp Phe Arg Asn Arg Gly 720 AAC CCA GGT CTA TGG ATT CTG GGG TGC CAC AAC TCA GAC TTT CGG AAC AGA CCC MET Thr Ala Leu Leu Lys Val Ser Ser Cys Asp Lys Asn Thr Gly Asp Tyr Tyr 738 ATG ACC CCC TTA CTG AAG GTT TCT AGT TGT GAC AAG AAC ACT GGT GAT TAT TAC Glu Asp Ser Tyr Glu Asp Ile Ser Ala Tyr Leu Leu Ser Lys Asn Asn Ala Ile 756 GAG GAC ACT TAT GAA CAT ATT TCA GCA TAC TTG CTG ACT AAA AAC AAT GCC ATT Glu Pro Arg Ser Phe Ser Gln Asn Ser Arg His Pro Ser Thr Arg Gln Lys Gln 774 GAA CCA AGA ACC TTC TCC CAG AAT TCA AGA CAC CCT AGC ACT AGG CAA AAG CAA Phe Asn Ala Thr Thr Ile Pro Glu Asn Asp Ile Glu Lys Thr Asp Pro Trp Phe 792 TTT AAT GCC ACC ACA ATT CCA CAA AAT GAC ATA CAG AAG ACT CAC CCT TGG TTT Ala His Arg Thr Pro MET Pro Lys Ile Gln Asn Val Ser Ser Ser Asp Leu Leu 810 GCA CAC AGA ACA CCT ATG CCT AAA ATA CAA AAT GTC TCC TCT ACT GAT TTG TTG MET Leu Leu Arg Gln Ser Pro Thr Pro His Gly Leu Ser Leu Ser Asp Leu Gln 828 ATG CTC TTG CGA CAG ACT CCT ACT CCA CAT GGG CTA TCC TTA TCT GAT CTC CAA Glu Ala Lys Tyr Glu Thr Phe Ser Asp Asp Pro Ser Pro Gly Ala Ile Asp Ser 846 GAA GCC AAA TAT GAG ACT TTT TCT GAT GAT CCA TCA CCT GGA GCA ATA CAC ACT Asn Asn Ser Leu Ser Glu MET Thr His Phe Arg Pro Gln Leu His His Ser Gly 864 AAT AAC AGC CTG TCT GAA ATG ACA CAC TTC ACC CCA CAG CTC CAT CAC ACT GGG Asp MET Val Phe Thr Pro Glu Ser Gly Leu Gln Leu Arg Leu Asn Glu Lys Leu 882 GAC ATG GTA TTT ACC CCT GAG TCA GGC CTC CAA TTA AGA TTA AAT CAG AAA CTG Gly Thr Thr Ala Ala Thr Glu Leu Lys Lys Leu Asp Phe Lys Val Ser Ser Thr 900 GGG ACA ACT GCA GCA ACA GAG TTC AAG AAA CTT CAT TTC AAA CTT TCT ACT ACA Ser Asn Asn Leu Ile Ser Thr Ile Pro Ser Asp Asn Leu Ala Ala Gly Thr Asp 918 TCA AAT AAT CTG ATT TCA ACA ATT CCA TCA GAC AAT TTG GCA GCA CCT ACT CAT Asn Thr Ser Ser Leu Gly Pro Pro Ser MET Pro Val His Tyr Asp Ser Gln Leu 936 AAT ACA AGT TCC TTA GGA CCC CCA ACT ATG CCA GTT CAT TAT CAT ACT CAA TTA Asp Thr Thr Leu Phe Gly Lys Lys Ser Ser Pro Leu Thr Glu Ser Gly Gly Pro 954 CAT ACC ACT CTA TTT GGC AAA AAG TCA TCT CCC CTT ACT GAG TCT GGT GCA CCT Leu Ser Leu Ser Glu Glu Asn Asn Asp Ser Lys Leu Leu Glu Ser Gly Leu MET 972 CTG AGC TTG ACT CAA CAA AAT AAT CAT TCA AAG TTG TTA CAA TCA CCT TTA ATC Asn Ser Gln Glu Ser Ser Trp Gly Lys Asn Val Ser Ser Thr Glu Ser Gly Arg 990 AAT ACC CAA CAA ACT TCA TGG CGA AAA AAT CTA TCG TCA ACA CAG ACT CGT ACC Leu Phe Lys Gly Lys Arg Ala His Gly Pro Ala Leu Leu Thr Lys Asp Asn Ala 1,008 TTA TTT AAA CGG AAA AGA GCT CAT GCA CCT CCT TTG TTG ACT AAA CAT AAT GCC Leu Phe Lys Val Ser Ile Ser Leu Leu Lys Thr Asn Lys Thr Ser Asn Asn Ser 1,026 TTA TTC AAA GTT AGC ATC TCT TTG TTA AAG ACA AAC AAA ACT TCC AAT AAT TCA Ala Thr Asn Arg Lys Thr His Ile Asp Gly Pro Ser Leu Leu Ile Glu Asn Ser 1,044 CCA ACT AAT ACA AAG ACT CAC ATT CAT CGC CCA TCA TTA TTA ATT GAG AAT AGT Pro Ser Val Trp Gln Asn Ile Leu Glu Ser Asp Thr Glu Phe Lys Lys Val Thr 1,062 CCA TCA GTC TGG CAA AAT ATA TTA GAA AGT GAC ACT CAG TTT AAA AAA GTG ACA Pro Leu Ile His Asp Arg MET Leu MET Asp Lys Asn Ala Thr Ala Leu Arg Leu 1,080 CCT TTG ATT CAT GAC AGA ATG CTT ATG GAC AAA AAT GCT ACA CCT TTC AGG CTA Asn His MET Ser Asn Lys Thr Thr Ser Ser Lys Asn MET Glu MET Val Gln Gln 1,098 AAT CAT ATG TCA AAT AAA ACT ACT TCA TCA AAA ACC ATG GAA ATG CTC CAA CAG Lys Lys Glu Gly Pro Ile Pro Pro Asp Ala Gln Asn Pro Asp MET Ser Phe Phe 1,116 AAA AAA GAG GGC CCC ATT CCA CCA GAT CCA CAA AAT CCA GAT ATG TCG TTC TTT Lys MET Leu Phe Leu Pro Glu Ser Ala Arg Trp Ile Gln Arg Thr His Gly Lys 1,134 AAG ATG CTA TTC TTG CCA GAA TCA CCA ACC TGG ATA CAA AGG ACT CAT GCA AAG Asn Ser Leu Asn Ser Gly Gln Gly Pro Ser Pro Lys Gln Leu Val Ser Leu Gly 1,152 AAC TCT CTG AAC TCT GGG CAA GGC CCC ACT CCA AAC CAA TTA GTA TCC TTA GCA Pro Glu Lys Ser Val Glu Gly Gln Asn Phe Leu Ser Glu Lys Asn Lys Val Val 1,170 CCA GAA AAA TCT GTG GAA GGT CAG AAT TTC TTG TCT GAG AAA AAC AAA GTG GTA Val Gly Lys Gly Gly Phe Thr Lys Asp Val Gly Leu Lys Glu MET Val Phe Pro 1,188 GTA GGA AAG GGT GAA TTT ACA AAG CAC GTA CGA CTC AAA GAG ATG CTT TTT CCA Ser Ser Arg Asn Leu Phe Leu Thr Asn Leu Asp Asn Leu His Glu Asn Asn Thr 1,206 AGC AGC ACA AAC CTA TTT CTT ACT AAC TTG GAT AAT TTA CAT GAA AAT AAT ACA His Asn Gln Glu Lys Lys Ile Gln Glu Glu Ile Glu Lys Lys Glu Thr Leu Ile 1,224 CAC AAT CAA CAA AAA AAA ATT CAG CAA CAA ATA GAA AAG AAG GAA ACA TTA ATC Gln Glu Asn Val Val Leu Pro Gln Ile His Thr Val Thr Gly Thr Lys Asn Phe 1,242 CAA GAG AAT GTA GTT TTG CCT CAG ATA CAT ACA CTG ACT GGC ACT AAG AAT TTC MET Lys Asn Leu Phe Leu Leu Ser Thr Arg Gln Asn Val Glu Gly Ser Tyr Glu 1,260 ATG AAC AAC CTT TTC TAA CTG ACC ACT AGG GAA AAT GTA GAA GGT TCA TAT GAG Gly Ala Tyr Ala Pro Val Leu Gln Asp Phe Arg Ser Leu Asn Asp Ser Thr Asn 1,278 GGG GCA TAT CCT CCA GTA CTT CAA CAT TTT AGG TCA TTA AAT GAT TCA ACA AAT Arg Thr Lys Lys His Thr Ala His Phe Ser Lys Lys Gly Glu Glu Glu Asn Leu 1,296 AGA ACA AAG AAA CAC ACA CCT CAT TTC TCA AAA AAA CGG CAG CAA CAA AAC TTG Glu Gly Leu Gly Asn Gln Thr Lys Gln Ile Val Glu Lys Tyr Ala Cys Thr Thr 1,314 CAA GGC TTG GGA AAT CAA ACC AAG CAA ATT CTA CAG AAA TAT CCA TGC ACC ACA Arg Ile Ser Pro Asn Thr Ser Gln Gln Asn Phe Val Thr Gln Arg Ser Lys Arg 1,332 AGC ATA TCT CCT AAT ACA AGC CAG CAG AAT TTT CTC ACG CAA CCT ACT AAG AGA Ala Leu Lys Gln Phe Arg Leu Pro Leu Glu Glu Thr Glu Leu Glu Lys Arg Ile 1,350 CCT TTG AAA CAA TTC AGA CTC CCA CTA GAA GAA ACA CAA CTT GAA AAA AGG ATA Ile Val Asp Asp Thr Ser Thr Gln Trp Ser Lys Asn MET Lys His Leu Thr Pro 1,368 ATT GTG GAT GAC ACC TCA ACC CAC TGG TCC AAA AAC ATG AAA CAT TTC ACC CCG Ser Thr Leu Thr Gln Ile Asp Tyr Asn Glu Lys Glu Lys Gly Alu Ile Thr Cln 1,386 AGC ACC CTC ACA CAG ATA GAC TAC AAT GAG AAG GAC AAA GGG GCC ATT ACT CAG Ser Pro Leu Ser Asp Cys Leu Thr Arg Ser His Ser Ile Pro Gln Ala Asn Arg 1,404 TCT CCC TTA TCA GAT TGC CTT ACG AGG ACT CAT AGC ATC CCT CAA GCA AAT AGA Ser Pro Leu Pro Ile Ala Lys Val Ser Ser Phe Pro Ser Ile Arg Pro Ile Tyr 1,422 TCT CCA TTA CCC ATT GCA AAG GTA TCA TCA TTT CCA TCT ATT AGA CCT ATA TAT Leu Thr Arg Val Leu Phe Gln Asp Asn Ser Ser His Leu Pro Ala Ala Ser Tyr 1,440 CTG ACC AGG GTC CTA TTC CAA GAC AAC TCT TCT CAT CTT CCA GCA GCA TCT TAT Arg Lys Lys Asp Ser Gly Val Gln Glu Ser Ser His Phe Leu Gln Gly Ala Lys 1,458 ACA AAG AAA GAT TCT GGG GTC CAA GAA AGC ACT CAT TTC TTA CAA CGA CCC AAA Lys Asn Asn Leu Ser Leu Ala Ile Leu Thr Leu Glu MET Thr Gly Asp Gln Arg 1,476 AAA AAT AAC CTT TCT TTA GCC ATT CTA ACC TTG GAG ATG ACT CGT CAT CAA AGA Glu Val Gly Ser Leu Gly Thr Ser Ala Thr Asn Ser Val Thr Tyr Lys Lys Val 1,494 GAG GTT GGC TCC CTG GGG ACA ACT GCC ACA AAT TCA GTC ACA TAC AAC AAA GTT Glu Asn Thr Val Leu Pro Lys Pro Asp Leu Pro Lys Thr Ser Gly Lys Val Glu 1,512 CAG AAC ACT GTT CTC CCG AAA CCA GAC TTG CCC AAA ACA TCT CGC AAA CTT GAA Leu Leu Pro Lys Val His Ile Tyr Gln Lys Asp Leu Phe Pro Thr Glu Thr Ser 1,530 TTG CTT CCA AAA GTT CAC ATT TAT CAG AAG CAC CTA TTC CCT ACG GAA ACT AGC Asn Gly Ser Pro Gly His Leu Asp Leu Val Glu Gly Ser Leu Leu Gln Gly Thr 1,548 AAT CCG TCT CCT GGC CAT CTG GAT CTC GTG CAA GGG AGC CTT CTT CAG CGA ACA Glu Gly Ala Ile Lys Trp Asn Glu Ala Asn Arg Pro Gly Lys Val Pro Phe Leu 1,566 GAG GGA GCG ATT AAC TGG AAT GAA CCA AAC AGA CCT CGA AAA CTT CCC TTT CTG Arg Val Ala Thr Glu Ser Ser Ala Lys Thr Pro Ser Lys Leu Leu Asp Pro Leu 1,584 AGA GTA GCA ACA GAA AGC TCT GCA AAG ACT CCC TCC AAC CTA TTG CAT CCT CTT Ala Trp Asp Asn His Tyr Gly Thr Gln Ile Pro Lys Glu Glu Trp Lys Ser Gln 1,602 GCT TGG GAT AAC CAC TAT GGT ACT CAG ATA CCA AAA GAA GAG TGG AAA TCC CAA Glu Lys Ser Pro Glu Lys Thr Ala Phe Lys Lys Lys Asp Thr Ile Leu Ser Leu 1,520 GAG AAG TCA CCA GAA AAA ACA GCT TTT AAG AAA AAG GAT ACC ATT TTG TCC CTG Asn Ala Cys Glu Ser Asn His Ala Ile Ala Ala Ile Asn Glu Gly Gln Asn Lys 1,638 AAC GCT TGT GAA AGC AAT CAT GCA ATA GCA CCA ATA AAT GAG CGA CAA AAT AAG Pro Glu Ile Glu Val Thr Trp Ala Lys Gln Gly Arg Thr Glu Arg Leu Cys Ser 1,656 CCC GAA ATA GAA GTC ACC TCC GCA AAG CAA CGT AGG ACT CAA AGG CTC TCC TCT Gln Asn Pro Pro Vnl Leu Lys Arg His Gln Arg Glu Ile Thr Arg Thr Thr Leu 1,674 CAA AAC CCA CCA CTC TTC AAA CCC CAT CAA CGC CAA ATA ACT CGT ACT ACT CTT Gln Ser Asp Gln Glu Glu Ile Asp Tyr Asp Asp Thr Ile Ser Val Glu MET Lys 1,692 CAG TCA GAT CAA GAG GAA ATT CAC TAT CAT CAT ACC ATA TCA GTT GAA ATG AAG Lys Glu Asp The Asp Ile Tyr Asp Glu Asp Glu Asn Gln Ser Pro Arg Ser Phe 1,710 AAG GAA GAT TTT GAC ATT TAT CAT GAG CAT GAA AAT CAC AGC CCC CGC AGC TTT Gln Lys Lys Thr Arg His Tyr Phe Ile Ala Ala Val Glu Arg Leu Trp Asp Tyr 1,728 CAA AAG AAA ACA CCA CAC TAT TTT ATT GCT GCA GTG GAG AGC CTC TGG GAT TAT Gly MET Ser Ser Ser Pro His Val Leu Arg Asn Arg Ala Gln Ser Gly Ser Val 1,746 CCG ATG AGT AGC TCC CCA CAT GTT CTA AGA AAC AGG GCT CAG AGT GGC ACT GTC Pro Gln Phe Lys Lys Val Val Phe Gln Glu Phe Thr Asp Gly Ser Phe Thr Gln 1,764 CCT CAG TTC AAG AAA GTT GTT TTC CAG CAA TTT ACT GAT CGC TCC TTT ACT CAG Pro Leu Tyr Arg Gly Glu Leu Asn Glu His Leu Gly Leu Leu Gly Pro Tyr Ile 1,782 CCC TTA TAC CCT GGA GAA CTA AAT GAA CAT TTG GGA CTC CTG GGG CCA TAT ATA Arg Ala Glu Val Glu Asp Asn Ile MET Val Thr Phe Arg Asn Gln Ala Ser Arg 1,800 AGA GCA GAA GTT GAA GAT AAT ATC ATG GTA ACT TTC AGA AAT CAG GCC TCT CGT Pro Tyr Ser Phe Tyr Ser Ser Leu Ile Ser Tyr Glu Glu Asp Gln Arg Gln Gly 1,818 CCC TAT TCC TTC TAT TCT AGC CTT ATT TCT TAT GAG GAA GAT CAG AGG CAA GGA Ala Glu Pro Arg Lys Asn Phe Val Lys Pro Asn Glu Thr Lys Thr Tyr Phe Trp 1,836 GCA GAA CCT AGA AAA AAC TTT GTC AAG CCT AAT GAA ACC AAA ACT TAC TTT TGG Lys Val Gln His His MET Ala Pro Thr Lys Asp Glu Phe Asp Cys Lys Ala Trp 1,854 AAA CTG CAA CAT CAT ATG GCA CCC ACT AAA GAT GAG TTT GAC TGC AAA GCC TGG Ala Tyr Phe Ser Asp Val Asp Leu Glu Lys Asp Val His Ser Gly Leu Ile Gly 1,872 GCT TAT TTC TCT GAT GTT GAC CTG GAA AAA CAT GTG CAC TCA GGC CTG ATT GGA Pro Leu Leu Val Cys His Thr Asn Thr Leu Asn Pro Ala His Gly Arg Gln Val 1,890 CCC CTT CTG CTC TGC CAC ACT AAC ACA CTG AAC CCT GCT CAT CCG AGA CAA CTG Thr Val Glu Glu Phe Ala Leu Phe Phe Thr Ile Phe Asp Glu Thr Lys Ser Trp 1,908 ACA CTA CAG GAA TTT GCT CTG TTT TTC ACC ATC TTT CAT GAG ACC AAA AGC TCG Thy Phe Thr Glu Asn MET Glu Arg Asn Cys Arg Ala Pro Cys Asn Ile Gln MET 1,926 TAC TTC ACT CAA AAT ATG CAA AGA AAC TGC ACC CCT CCC TGC AAT ATC CAG ATG Glu Asp Pro Thr Phe Lys Glu Asn Thr Arg Phe His Ala Ile Asn Gly Tyr Ile 1,944 CAA GAT CCC ACT TTT AAA CAG AAT TAT CGC TTC CAT GCA ATC AAT CGC TAC ATA MET Asp Thr Leu Pro Gly Leu Val MET Ala Gln Asp Gln Arg Ile Arg Trp Tyr 1,962 ATG CAT ACA CTA CCT GGC TTA GTA ATG GCT CAG GAT CAA AGG ATT CGA TCG TAT Leu Leu Ser MET Gly Ser Asn Glu Asn Ile His Ser Ile His Phe Ser Gly His 1,980 CTC CTC AGC ATG CGC AGC AAT CAA AAC ATC CAT TCT ATT CAT TTC ACT CCA CAT Val Phe Thr Val Arg Lys Lys Glu Glu Tyr Lys MET Ala Leu Tyr Asn Leu Tyr 1,998 GTG TTC ACT CTA CCA AAA AAA CAG GAG TAT AAA ATG GCA CTG TAC AAT CTC TAT Pro Gly Val Phe Glu Thr Val Glu MET Leu Pro Ser Lys Ala Gly Ile Trp Arg 2,016 CCA CGT GTT TTT GAC ACA GTG GAA ATG TTA CCA TCC AAA GCT GGA ATT TCC CGG Val Glu Cys Leu Ile Gly Glu His Leu His Ala Gly MET Ser Thr Leu Phe Leu 2,034 GTG GAA TGC CTT ATT CCC GAC CAT CTA CAT CCT CGG ATG AGC ACA CTT TTT CTG Val Tyr Ser Asn Lys Cys Glu Thr Pro Leu Gly MET Ala Ser Gly His Ile Arg 2,052 GTG TAC AGC AAT AAG TGT CAG ACT CCC CTG GGA ATG GCT TCT GGA CAC ATT AGA Asp Phe Gln Ile Thr Ala Ser Gly Gln Tyr Gly Gln Trp Ala Pro Lys Leu Ala 2,070 CAT TTT CAG ATT ACA GCT TCA CGA CAA TAT GCA CAG TGG GCC CCA AAG CTG GCC Arg Leu His Tyr Ser Gly Ser Ile Asn Ala Trp Set Thr Lys Glu Pro Phe Ser 2,088 AGA CTT CAT TAT TCC GGA TCA ATC AAT GCC TGG AGC ACC AAG GAG CCC TTT TCT Trp Ile Lys Val Asp Leu Leu Ala Pro MET Ile Ile His Gly Ile Lys Thr Gln 2,106 TGC ATC AAG GTG CAT CTG TTG GCA CCA ATG ATT ATT CAC GGC ATC AAG ACC CAG Gly Ala Arg Gln Lys Phe Ser Ser Leu Tyr Ile Ser Gln Phe Ile Ile MET Tyr 2,124 GGT GCC CGT CAG AAG TTC TCC AGC CTC TAC ATC TCT CAG TTT ATC ATC ATG TAT Ser Leu Asp Gly Lys Lys Trp Gln Thr Tyr Arg Gly Asn Ser Thr Gly Thr Leu 2,142 AGT CTT GAT GGG AAG AAG TGG CAG ACT TAT CGA GGA AAT TCC ACT CCA ACC TTA MET Val Phe Phe Gly Asn Val Asp Ser Ser Gly Ile Lys His Asn Ile Phe Asn 2,160 ATG GTC TTC TTT GGC AAT CTC CAT TCA TCT CCC ATA AAA CAC AAT ATT TTT AAC Pro Pro Ile Ile Ala Arg Tyr Ile Arg Leu His Pro Thr His Tyr Ser Ile Arg 2,178 CCT CCA ATT ATT GCT CGA TAC ATC CGT TTG CAC CCA ACT CAT TAT AGC ATT CCC Ser Thr Leu Arg MET Glu Leu MET Gly Cys Asp Leu Asn Ser Cys Ser MET Pro 2,196 AGC ACT CTT CGC ATG GAG TTG ATG CCC TGT GAT TTA AAT ACT TCC AGC ATG CCA Leu Gly MET Glu Ser Lys Ala Ile Ser Asp Ala Gln Ile Thr Ala Ser Ser Tyr 2,214 TTG GCA ATG GAG AGT AAA GCA ATA TCA CAT GCA CAG ATT ACT GCT TCA TCC TAC Phe Thr Asn MET Phe Ala Thr Trp Ser Pro Ser Lys Ala Arg Leu His Leu Gln 2,232 TTT ACC AAT ATG TTT GCC ACC TGG TCT CCT TCA AAA GCT CGA CTT CAC CTC CAA Gly Arg Ser Asn Ala Trp Arg Pro Gln Val Asn Asn Pro Lys Glu Trp Leu Gly 2,250 GGG AGG ACT AAT GCC TGG AGA CCT CAG GTG AAT AAT CCA AAA CAG TGG CTG CAA Val Asp Phe Gln Lys Thr MET Lys Val Thr Gly Val Thr Thr Gln Gly Val Lys 2,268 GTG GAC TTC CAG AAG ACA ATG AAA CTC ACA GGA GTA ACT ACT CAG GGA CTA AAA Ser Leu Leu Thr Ser MET Tyr Val Lys Glu Phe Leu Ile Ser Ser Ser Gln Asp 2,286 TCT CTG CTT ACC ACC ATG TAT GTG AAG GAG TTC CTC ATC TCC ACC ACT CAA CAT Gly His Gln Trp Thr Leu Phe Phe Gln Asn Gly Lys Val Lys Val Phe Gln Gly 2,304 GGC CAT CAG TGG ACT CTC TTT TTT CAG AAT CCC AAA CTA AAC CTT TTT CAG CCA Asn Gln Asp Ser Phe Thr Pro Val Val Asn Ser Leu Asp Pro Pro Leu Leu Thr 2,322 AAT CAA GAC TCC TTC ACA CCT GTG GTG AAC TCT CTA GAC CCA CCG TTA CTG ACT Arg Tyr Leu Arg Ile His Pro Gln Ser Trp Val His Gln Ile Ala Leu Arg MET 2,340 CGC TAC CTT CGA ATT CAC CCC CAG AGT TGG CTC CAC CAG ATT CCC CTG ACC ATG Glu Val Leu Gly Cys Glu Ala Gln Asp Leu Tyr End 2,352 GAG GTT CTG GCC TGC GAG GCA CAG GAC C TC TAC TGA GGGTGGCCACTGCATGCCCACCTGCCACTG CCGTCACCTCTCCCTCCTCAGCTCCAGGGCA TGTGTCCCTCCCTGGCTTGCTTCTACCTTTGTGCTAAATCCTAGCAGACACTCCCTTG AAGCCTCCTGAATT AACTATCATGACTCCTGCATTTCTTTGGTGGGGGGCCAGGAGGCTGCATCCATTTTAACTTAACTCTTACCTA TT TTCTGCAGCTGCTCCCAGA

By way of example, one compound of this invention contains a region X comprising the amino acid sequence of Ser-760 to Pro-1000 followed by the amino acid sequence of Asp-1582 to Arg-1708. That compound thus comprises the polypeptide sequence of Ala-20 to Pro-1000 covalently linked by a peptide bond to amino acids Asp-1582 to Tyr-2351. Another exemplary compound contains a region X comprising the amino acid sequence Ser-760 to Thr-778 followed by the sequence Pro-1659 to Arg-1708. That compound thus comprises the polypeptide sequence Ala-20 to Thr-778 covalently linked by a peptide bond to the sequence Pro-1659 through Tyr-2351. Still another exemplary compound contains a region X comprising the amino acid sequence Ser-760 to Thr-778 followed by the sequence Glu-1694 to Arg-1708. That compound thus comprises the polypeptide sequence Ala-20 to Thr-778 covalently linked by a peptide bond to amino acids Glu-1694 through Tyr-2351.

These exemplary compounds are depicted schematically in Table 2.

The amino acid sequence represented by X should be selected so that it does not substantially reduce the procoagulant activity of the molecule, which activity can be conveniently assayed by conventional methods. Compound (2) of Table 2 is a presently preferred embodiment.

The procoagulant protein may be produced by appropriate host cells transformed by factor VIII:C DNA which has been specifically altered by use of any of a variety of site-specific mutagenesis techniques which will be familiar to those of ordinary skill in the art of recombinant DNA.

The starting materials may be a DNA sequence which codes for the complete factor VIII:C molecule, e.g., the complete human factor VIII:C as shown in Table 1, a truncated version of that sequence, or it may comprise segments of that DNA sequence, so long as the starting materials contain at least sufficient DNA to code for the amino acid sequences of the desired polypeptide.

The procoagulant proteins of the present invention, in addition to lacking a substantial amino acid segment of human factor VIII:C, also have fewer potential N-glycosylation sites than human factor VIII. Preferably, at least one N-glycosylation site has been deleted. More preferably, 18 of the 25 potential N-glycosylation sites are not in the molecule. In still more preferred embodiments, up to 19 of the 25 potential N-glycosylation sites are removed. While not wishing to be bound by theory, it is presently believed that the antibodies to factor VIII:C which are directed to antigenic determinants contained in the protein segment deleted in accordance with this invention, i.e., in the amino acid segement itself or in the carbohydrate portion of the glycosylated protein, will not neutralize the procoagulant proteins of the present invention. Moreover, the fact that the procoagulants of the present invention lack many of the sites for non-human glycosylation by the non-human mammalian or other cells used to produce the proteins is also belived to reduce the antigenicity of that protein, and lessen the likelihood of developing antibodies to the procoagulants. This may enable facilitating the treatment of patients in need of procoagulant therapy.

I contemplate that my compounds can be produced by recombinant DNA techniques at a much lower cost than is possible for production of human factor VIII. The host organisms should more efficiently process and express the substantially simpler molecules of this invention.

The compounds of this invention can be formulated into pharmaceutically acceptable preparations with parenterally acceptable vehicles and excipients in accordance with procedures known in the art.

The pharmaceutical preparations of this invention, suitable for parenteral administration, may conveniently comprise a sterile lyophilized preparation of the protein which may be reconstituted by addition of sterile solution to produce solutions preferably isotonic with the blood of the recipient. The preparation may be presented in unit or multi-dose containers, e.g. in sealed ampoules or vials. Their use would be analogous to that of human factor VIII, appropriately adjusted for potency.

One method by which these proteins can be expressed is by use of DNA which is prepared by cutting a full-length factor VIII:C DNA with the appropriate restriction enzymes to remove a portion of the DNA sequence that codes for amino acids 760 to 1708 of human factor VIII:C. The cut DNA is then ligated with an oligonucleotide that resects the cut DNA and maintains the correct translational reading frame.

Preparation of the cDNA has been set forth in detail in U.S. patent applications Ser. Nos. 546,650 and 644,086, supra. A pSP64 recombinant clone containing the nucleotide sequence depicted in Table 1, designated as pSP64-VIII, is on deposit at the American Type Culture Collection under Accession Number ATCC 39812.

Restriction endonucleases are used to obtain cleavage of the human factor VIII:C cDNA, hereinafter the DNA source sequence, at appropriate sites in the nucleotide sequence. Unless otherwise noted, restriction endonucleases are utilized under the conditions and in the manner recommended by their commercial suppliers. The restriction endonucleases selected herein are those which will enable one to excise with substantial specificity sequences that code for the portion of the factor VIII:C molecule desired to be excised. BamHI and SacI are particularly useful endonucleases. However, the skilled artisan will be able to utilize other restriction endonucleases chosen by conventional selection methods. The number of nucleotides deleted may vary but care should be taken to insure that the reading frame of the ultimate cDNA sequence will not be affected.

The resulting DNA fragments are then purified using conventional techniques such as those set forth in Maniatis et al., Molecular Cloning, A Laboratory Manual (Cold Spring Harbor Laboratory 1982) the disclosure of which is incorporated herein by reference, and Proc. Natl. Acad. Sci. 76:615-619 (1979). The purified DNA is then ligated to form the sequence encoding the polypeptide of the preferred invention. When necessary or desirable, the ligation may be within an oligonucleotide that resects the cut DNA and maintains the correct translational reading frame using standard ligation conditions. Ligation reactions are carried on as described by Maniatis et al., supra at 2453-6 using the buffer described at page 246 thereof and using a DNA concentration of 1-100 ug/ml, at a temperature of 23.degree. C. for blunt ended DNA and 16.degree. C. for "sticky ended" DNA. The following double-stranded oligonucleotide is useful when there is BamHI/SacI deletion such as described infra,

but other oligonucleotides can be selected by the skilled artisan depending upon the deletions made and reaction conditions.

The DNA sequences encoding the novel procoagulant polypeptides can, in addition to other methods, be derived from the sequence of human factor VIII:C DNA by application of oligonucleotide-mediated deletion mutagenesis, often referred to as "loopout" mutagenesis, as described for example in Morinaga, Y. et al. Biotechnology, 636-639 (1984).

The new DNA sequences containing the various deletions can then be introduced into appropriate vectors for expression in mammalian cells. The procoagulant activity produced by the transiently transfected or stably transformed host cells may be measured by using standard assays for blood plasma samples.

The eukaryotic cell expression vectors described herein may be synthesized by techniques well known to those skilled in this art. The components of the vectors such as the bacterial replicons, selection genes, enhancers, promoters, and the like may be obtained from natural sources or synthesized by known procedures. See Kaufman et al., J. Mol. Biol., 159: 51-521 (1982); Kaufman, Proc. Natl. Acad. Sci. 82: 689-693 (1985).

Established cell lines, including transformed cell lines, are suitable as hosts. Normal diploid cells, cell strains derived from in vitro culture of primary tissue, as well as primary explants (including relatively undifferentiated cells such as haematopoeitic stem cells) are also suitable. Candidate cells need not be genotypically deficient in the selection gene so long as the selection gene is dominantly acting.

The host cells preferably will be established mammalian cell lines. For stable integration of the vector DNA into chromosomal DNA, and for subsequent amplification of the integrated vector DNA, CHO (Chinese hamster ovary) cells are presently preferred. See U.S. Pat. No. 4,399,216. Alternatively, the vector DNA could include all or parts of the bovine papilloma virus genome (Lusky et al., Cell, 36: 391-401 (1984) and be carried in cell lines such as C127 mouse cells as a stable episomal element. Other usable mammalian cell lines include HeLa, COS-1 monkey cells, melanoma cell lines such as Bowes cells, mouse L-929 cells, 3T3 lines derived from Swiss, Balb-c or NIH mice, BHK or HaK hamster cells lines and the like.

Stable transformants then are screened for expression of the procoagulant product by standard immunological or enzymatic assays. The presence of the DNA encoding the procoagulant proteins may be detected by standard procedures such as Southern blotting. Transient expression of the procoagulant genes during the several days after introduction of the expression vector DNA into suitable host cells such as COS-1 monkey cells is measured without selection by enzymatic or immunologic assay of the proteins in the culture medium.

The invention will be further understood with reference to the following illustrative embodiments, which are purely exemplary, and should not be taken as limiting the true scope of the present invention, as described in the claims.

10 .mu.g. of the plasmid pACE, a pSP64 (Promega Biotec, Madison, Wis.) derivative, containing nucleotides 562-7269 of human factor VIII:C cDNA (nucleotide 1 is the A of the ATG initiator methionine codon) was subjected to partial BamHI digestion in 100 ul containing 50 mM Tris.HCl ph 8.0, 50 mM MgCl.sub.2, and 2.4 units BamHI (New England Biolabs) for 30 minutes at 37.degree. C. The reaction was terminated by the addition of EDTA to 20 mM and then extracted once with phenol, once with chloroform , ethanol precipitated and pelleted by centrifugation. DNA was redissolved, cleaved to completion in 50 ul using 40 units SacI for 1.5 hours at 37.degree. C. DNA was then electrophoresed through a buffered 0.6% agarose gel. An 8.1 kb fragment corresponding to the partial BamHI-SacI fragment of pACE lacking only the sequence corresponding to nucleotides 2992-4774 of the factor VIII:C sequence was purified from the gel using the glass powder technique described in Proc. Nat. Acad. Sci. 76: 615-619 (1979). Purified DNA was ligated with 100 pmoles of the following double-stranded oligonucleotide

using standard ligation conditions. The DNA sequence removed represents the deletion of 584 amino acid sequence beginning with amino acid 998 and continuing through 1581. The oligonucleotide inserted, however, encodes amino acids corresponding to 998-1000. Therefore, the polypeptide encoded contains deletion of 581 amino acids.

DNA was then used to transform competent E. coli bacteria, and DNA from several ampicillin resistant transformants was analyzed by restriction mapping to identify a plasmid harboring the desired SacI-BamHI deletion mutant. DNA from this plasmid was digested to completion with KpnI, which cleaves the plasmid uniquely at nucleotide 1816 of the factor VIII:C coding sequence. This DNA was ligated with a KpnI DNA fragment containing nucleotides 1-1815 of factor VIII:C DNA and a synthetic SalI site at nucleotides -11 to -5 and then used to transform competent E. coli bacteria.

Plasmid DNA was isolated and oriented by restriction mapping to identify a plasmid, pBSdK, containing the correct 5' to 3' orientation of the KpnI insert. SalI digestion, which excises the entire polypeptide coding region from the plasmid, was performed and the DNA electrophoresed through a buffered 0.6% agarose gel. The 5.3 Kb SalI fragment was purified from the gel as described above. This DNA fragment was ligated with XhoI cut pXMT2 DNA to give rise to plasmid pDGR-2. pXMT2 is a plasmid capable of expressing heterologous genes when introduced into mammalian cells such as the COS-1 African Green Monkey kidney cell line, and is a derivative of the expression vectors described in Kaufman, supra at 689-93. The expression elements are the same as described for plasmid pQ2 except that it contains a deletion of the adenovirus major late promoter extending from -45 to +156 with respect to the transcription start site of the adenovirus major late promoter. mRNA expression in pXMT is driven by the SV40 late promoter. The bacterial replicon, however, has been substituted to render bacteria containing the vector resistant to ampicillin rather than tetracycline. pXMT2 contains a unique Xho I site at a position which allows for expression of inserted cDNA from the SV40 late promoter. This Xho I site is convenient for inserting factor VIII:C cDNA constructs since these are flanked by SalI sites.

Restriction mapping of transformants identified a plasmid, pDGR-2, containing the correct 5' to 3' orientation of the polypeptide coding sequence relative to the direction of transcription from the SV40 late promoter. pDGR-2 is on deposit at the American Type Culture Collection under Accession number 53100.

Other novel procoagulant proteins may be obtained from constructs produced by oligonucleotide mediated deletion mutagenesis, using for example the "loopout" mutagenesis techniques as described in Morinaga et al., supra. The deletion mutagenesis is performed using expression plasmid pDGR-2 or any other appropriate plasmid or bacteriophage vector. Other methods for oligonucleotide mediated mutagenesis employing single stranded DNA produced with M13 vectors and the like are also suitable. See Zoller et al., Nucl. Acids Res. 10: 648-6500 (1982). For example, these deletions can be produced using the oligonucleotides

to cause deletions in factor VIII:C cDNA from nucleotides (A) 2334 to 4974 or (B) 2334 to 5079. The proteins encoded by these constructs contain deletions of (A) 880 and (B) 915 amino acids relative to Factor VIII:C.

The deleted constructs are tested directly, or after subcloning into appropriate expression vectors, in order to determine if the novel proteins possess procoagulant activity. Procoagulant activity was assayed as described in Examples 3 and 4.

Expression of Procoagulant Molecules in COS Monkey Cells The expression plasmids containing the modified cDNA's prepared as in Examples 1 or 2 and the full-length cDNA, pXMT-VIII, were introduced into COS-1 cells via the DEAE-dextran transfection protocol. Sompayrac and Dana 1981, Proc. Natl. Acad. Sci. 78: 7575-7578. Conditioned media was harvested 48 hours post-transfection and assayed for factor VIII-type activity as described in Toole et. al., 1984, Nature 312:342-347. The results of the experiment are summarized in Table 3. Both plasmids containing the modified cDNAs yielded procoagulant activity and, moreover, the activity was greater than that obtained using wild type cDNA. From these data it was concluded that removal of up to 880 amino acids (95,000 daltons) in a defined domain of human factor VIII does not destroy cofactor activity. Furthermore, these abridged procoagulant proteins retain their ability to be activated by thrombin.

The plasmids indicated were transfected into COS cells and 48 hr. post-transfection the conditioned media taken for assay by the Kabi Coatest factor VIII:C method (chromogenic activity) and by the one-stage activated partial thromboplastin time (APTT) coagulation assay (Clotek activity) using factor VIII:C deficient plasma as described (Toole, Nature 1984). For thrombin (IIa) activation, samples were pretreated 1-10 min, with 0.2 units/ml thrombin (IIa) at room temperature. Activation coefficients are provided in parentheses. Activity from media from the wild-type (pXMT-VIII) transfection was too low to directly measure Clotek activity before thrombin activation. From other experiments where the wild type factor VIII activity was concentrated, it was demonstrated to be approximately 30-fold activatable.

(A) Expression of pDGR-2

The procoagulant expression vector containing a deletion (relative to the Factor VIII:C cDNA) of 581 amino acids (pDGR-2) was transfected with plasmid pAdD26SV(A)#3 (10 ug pDGR-2:1 ug pAdD26SV(A)#3) by CaPO.sub.4 coprecipitatio CHO DHFR deficient cells (DUKX-B11) and transformants isolated and grown in increasing concentrations of MTX as described by Kaufman et. al., (1985). One transformant designated J1 exhibited the following activities as a function of resistance to increasing concentrations of MTX.

(B) Expression of pLA-2

The procoagulant expression vector containing a deletion of 880 amino acids (pLA-2) was introduced into CHO DHFR deficient cells (DUKX-B11, Chasin and Urlaub, PNAS 77: 4216-4220, 1980 by protoplast fusion as described (Sandri-Goldin et al. Mol. Cell. Biol. 1: 743-752). After fusion, fresh medium containing 100 ug/ml of kanamycin, and 10 ug/ml of each of thymidine, adenosine, deoxyadenosine, penicillin, and streptomycin and 10% dialyzed fetal calf serum was added to each plate. The kanamycin was included to prevent the growth of any bacteria which had escaped conversion to protoplasts. Four days later the cells were subcultured 1:15 into alpha-media with 10% dialyzed fetal calf serum, penicillin, and streptomycin, but lacking the nucleosides. Colonies appeared after 10-12 days after subculturing cells into selective media. A group of 8 transformants were pooled and grown in sequentially increasing concentrations of MTX starting at 0.02 uM with steps to 0.1, 0.2, and 1.0 uM MTX (LA 3-5 cells; ATCC No. CRL 10/01). Results of factor VIII-type activity in cells resistant to increasing concentrations of MTX is shown below.