Reduction in the level of hyaluronan binding protein 1 (HABP1) is associated with loss of sperm motility

Abstract

Hyaluronan binding protein 1 (HABP1) was reported to be present on human sperm surface and its involvement in fertilization has already been elucidated (Mol. Repro. Dev. 38 (1994) 69). In the present communication, we report a significant reduction in the level of this protein in sperms from asthenozoospermic and oligozoospermic patients as compared to normozoospermic one. Further evidence of the absence of HABP1 in sperms, having motility <20% is documented, which again is a determining factor for fertilization. HABP1 was quantitatively determined using anti-HABP1 antibody from sperm extracts isolated from semen samples of both the fertile and infertile groups demonstrating low sperm motility. Sperm samples with low motility revealed a significant reduction in the level of HABP1 in immunoblot detection as well as immunolocalization experiment. It suggests that decreased HABP1 level may be associated with low motility of sperms, which in turn might cause infertility in the patient. Thus, the sperm surface HABP1 level can be correlated with the degree of sperm motility, an important criteria for fertilization.