Muñoz Mariana Weigel, Ernesto Juan I, Bluguermann Carolina, Busso Dolores, Battistone María A, Cohen Débora J, Cuasnicú Patricia S
Instituto de Biologia y Medicina Experimental, CONICET, Vuelta de Obligado 2490, Buenos Aires 1428, Argentina.
J Androl. 2012 Nov-Dec;33(6):1360-70. doi: 10.2164/jandrol.112.016725. Epub 2012 May 31.
Cysteine-rich secretory protein 2 (CRISP2) is a testicular sperm protein proposed to be involved in fertilization. With the aim of examining the relevance of CRISP2 for fertility and its potential use as a target for contraception, in the present work, male and female rats were immunized with recombinant CRISP2 coupled to maltose-binding protein (MBP) and evaluated for their subsequent fertility. As controls, animals were injected with either MBP or recombinant CRISP1. Enzyme-linked immunosorbent assay of sera collected at different intervals after immunization indicated that CRISP2 immunization raised specific antibodies in both sexes, with levels that increased as a function of time. Western blot studies revealed that anti-CRISP2 sera were capable of recognizing CRISP2 in testicular, epididymal, and sperm extracts, whereas histological studies showed no evidence of autoimmune orchitis or epididymitis. Indirect immunofluorescence experiments revealed the ability of anti-CRISP2 sera to recognize the native sperm protein in fresh, capacitated, and ionophore-induced acrosome-reacted cells. Moreover, anti-CRISP2 sera significantly inhibited the sperm ability to penetrate zona-free eggs, confirming the role of CRISP2 in rat gamete fusion. In spite of the presence of circulating anti-CRISP2 antibodies capable of inhibiting the sperm fertilizing ability, mating studies revealed no effects of CRISP2 immunization on male or female fertility, in contrast to the significant inhibition observed in both sexes in animals injected with CRISP1. Together, these observations indicated the immunogenic properties of testicular CRISP2 but do not support CRISP2 as a target for immunocontraception or as a molecule responsible for generating autoimmune orchitis or immunoinfertility.
富含半胱氨酸的分泌蛋白2（CRISP2）是一种睾丸精子蛋白，被认为与受精过程有关。为了研究CRISP2与生育力的相关性及其作为避孕靶点的潜在用途，在本研究中，用与麦芽糖结合蛋白（MBP）偶联的重组CRISP2对雄性和雌性大鼠进行免疫，并评估其随后的生育力。作为对照，给动物注射MBP或重组CRISP1。对免疫后不同时间采集的血清进行酶联免疫吸附测定表明，CRISP2免疫在两性中均产生了特异性抗体，其水平随时间增加。蛋白质印迹研究表明，抗CRISP2血清能够识别睾丸、附睾和精子提取物中的CRISP2，而组织学研究未发现自身免疫性睾丸炎或附睾炎的证据。间接免疫荧光实验表明，抗CRISP2血清能够识别新鲜、获能和离子载体诱导的顶体反应细胞中的天然精子蛋白。此外，抗CRISP2血清显著抑制精子穿透无透明带卵的能力，证实了CRISP2在大鼠配子融合中的作用。尽管存在能够抑制精子受精能力的循环抗CRISP2抗体，但交配研究表明，与注射CRISP1的动物中两性均观察到的显著抑制相反，CRISP2免疫对雄性或雌性生育力没有影响。这些观察结果共同表明睾丸CRISP2具有免疫原性，但不支持将CRISP2作为免疫避孕靶点或作为导致自身免疫性睾丸炎或免疫性不育的分子。
