D'Cruz O J, Toth C A, Haas G G
Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City 73190, USA.
Biol Reprod. 1996 Jun;54(6):1217-28. doi: 10.1095/biolreprod54.6.1217.
The pathogenesis of antisperm antibody (ASA)-mediated infertility is postulated to be related in part to complement (C)-dependent sperm dysfunction in the female genital tract. We have previously demonstrated that C can be involved in ASA-mediated sperm injury by the deposition of activated C3 fragments and the assembly of terminal membrane attack complex (C5b-9) leading to C3-mediated sperm binding to neutrophils or C5b-9-mediated sperm motility loss. This study evaluated the protective effect of recombinant soluble C receptor type 1 (sCR1) on ASA-and C-mediated neutrophil/sperm interaction, neutrophil aggregation, and sperm motility loss. Motile sperm with or without neutrophils were incubated in the presence of 10% C-fixing ASA+ serum or ASA- control sera in the presence or absence of sCR1. After defined incubation periods, the following neutrophil and sperm parameters were evaluated: 1) neutrophil aggregation (by the flow cytometric pulse processing method), 2) sperm phagocytosis (by light microscopy), 3) the deposition of C3 cleavage fragments (C3b, iC3b, and C3d) on motile sperm (by immunofluorescence flow cytometry), and 4) the relation between sperm motility loss and sperm-bound C3d. Only the coincubation of neutrophils with sperm in the presence of C-fixing ASA+ sera resulted in marked neutrophil aggregation (20.5 +/- 0.26% vs. 2.4% +/- 1.6; p < 0.0001) and a concomitant increase in neutrophils containing ingested sperm (71 +/- 5.8% vs. 3.5%; p < 0.0001). Soluble CR1 inhibited ASA- and C-mediated neutrophil aggregation by 46% and sperm phagocytosis by 57%. Motile sperm incubated with C-fixing ASA- sera showed a time-dependent increase in the binding of C3 fragments as detected by flow cytometry using anti-iC3b neoantigen, anti-C3c, and anti-C3d monoclonal antibodies (mAbs). A negative correlation (r2 = -0.930; p < 0.001) was found between the increase in sperm-associated C3d fluorescence and the percentage motile sperm in the presence of ASA- sera. Soluble CR1 (200 micrograms/ml) maximally inhibited the binding of anti-C3b, anti-C3c, and anti-C3d mAbs to sperm by 96%, 83%, and 72%, respectively. Thus, sCR1 abrogated the binding of C3 fragments to human sperm and fully protected sperm from C5b-9-mediated sperm immobilization. These findings suggested the therapeutic potential of sCR1 as an intravaginal pharmacophore to prevent C-dependent sperm dysfunction and related inflammatory events in the female genital tract.
抗精子抗体（ASA）介导的不孕症发病机制据推测部分与女性生殖道中补体（C）依赖性精子功能障碍有关。我们之前已经证明，补体可通过活化的C3片段沉积和末端膜攻击复合物（C5b - 9）的组装参与ASA介导的精子损伤，从而导致C3介导的精子与中性粒细胞结合或C5b - 9介导的精子运动能力丧失。本研究评估了重组可溶性C1型受体（sCR1）对ASA和C介导的中性粒细胞/精子相互作用、中性粒细胞聚集及精子运动能力丧失的保护作用。将有或无中性粒细胞的活动精子在存在或不存在sCR1的情况下，于10%补体固定的ASA +血清或ASA -对照血清中孵育。在规定的孵育时间后，评估以下中性粒细胞和精子参数：1）中性粒细胞聚集（通过流式细胞术脉冲处理方法），2）精子吞噬作用（通过光学显微镜），3）活动精子上C3裂解片段（C3b、iC3b和C3d）的沉积（通过免疫荧光流式细胞术），以及4）精子运动能力丧失与精子结合的C3d之间的关系。仅在补体固定的ASA +血清存在下中性粒细胞与精子共同孵育才导致显著的中性粒细胞聚集（20.5±0.26%对2.4%±1.6；p < 0.0001），同时含有吞噬精子的中性粒细胞数量随之增加（71±5.8%对3.5%；p < 0.0001）。可溶性CR1抑制ASA和C介导的中性粒细胞聚集达46%，抑制精子吞噬作用达57%。用补体固定的ASA -血清孵育的活动精子，使用抗iC3b新抗原、抗C3c和抗C3d单克隆抗体（mAb）通过流式细胞术检测发现，C3片段的结合呈时间依赖性增加。在ASA -血清存在下，精子相关C3d荧光增加与活动精子百分比之间呈负相关（r2 = -0.930；p < 0.001）。可溶性CR1（200微克/毫升）分别最大程度地抑制抗C3b、抗C3c和抗C3d mAb与精子的结合达96%、83%和72%。因此，sCR消除了C3片段与人类精子的结合，并完全保护精子免受C5b - 9介导的精子制动。这些发现提示sCR1作为一种阴道内药效基团，在预防女性生殖道中C依赖性精子功能障碍及相关炎症事件方面具有治疗潜力。
