Complement inhibitor of rat cell membrane resembling mouse Crry/p65.

Neuraminidase-treated rat erythrocytes are resistant to homologous rat C although they are readily hemolyzed by heterologous serum C via the alternative pathway. We established a mAb, mAb512, which allows for hemolysis of neuraminidase-treated rat erythrocytes by homologous rat serum. mAb512 detected rat erythrocyte membrane components with molecular masses of 65 kDa and 55 kDa by Western blotting analysis. Furthermore, mAb512 caused C3b deposition on rat myeloma cells after treatment with rat serum. 512Ag was purified by use of an immunosorbent column prepared with mAb512. Partial sequencing of 512Ag peptides showed significant homology to mouse Crry/p65 indicating that 512Ag could be the rat counterpart of mouse Crry/p65.