Immuno-contraceptive potential of sperm specific LDHC4 and SPAM-1 (PH-20) sub units in dog

摘要

PH-20 (Spam-1) antigen appears to be a bi-functional sperm plasma membrane protein with hyaluronidase activity and its role is related to cumulus penetration as well as zona binding. (LDH-C4) is a key enzyme, distributed specifically in testis and is highly immunogenic, function of which relates to energy metabolism and capacitation of the sperm. Therefore, in this study, we observed the effect of purified native PH-20 and LDH-C4 antigens on sperm function and morphology in dog. Native PH-20 (46, 32 kDa) and LDH-C4 (36, 30, 28) sub units, purified from dog sperm SDS- extracts were used to test as immunocontraceptive candidates in stray dog. Dogs 1, 2, 3, 4, 5/6 and 7/8 were immunized with 46, 32, 36, 30/28, 46/32, 36/30/28 kDa sub units respectively by i/m route and semen was analysed at weekly intervals. High titre of 3200 - 6400 was achieved in all dogs after three boosters. Immune response in treated dogs was confirmed by increase in Ig level in blood serum and reaction of partially purified serum Ig of immunized dogs with respective antigens in double immune diffusion and immunoblots. Immunization of dogs either with individual PH-20/ LDHC sub units or pooled PH-20/LDHC4 sub units showed a significant effect on sperm count, percent motility, viability, HOST and sperm morphology. All the sperm parameters declined to a significant level (p 4 (36/30/28 kDa) sub units had an immunocontraceptive potential in dog.