cellular product of HBsHBs MAb exhibited stronger cytotoxicity to T cells from mouse spleens than that of HBs alone. 17328890 It suggested that the mechanism in adverse Effects of HBs on Sperm Functions 5 Effects of HBs on Sperm Functions effects caused by HBsHBs MAb complex might be different from the mechanism by which HBs MAb Sodium laureth sulfate neutralized the biological activity of HBs in sperm cells. Lipid peroxidation of the sperm membrane can result in the loss of membrane integrity including 
sperm-oocyte fusion and the ability to undergo acrosomal exocytosis and increase in membrane permeability, causing a loss of capacity to regulate the intracellular concentrations of ions involved in the sperm movement. In the present study, the sperm cells exposed to 50 mg/ml of HBs for 3 h had significantly higher level of MDA than that in the control group. The MDA levels rose with increasing concentrations of HBs. These suggested that HBs exposure was able to induce lipid peroxidation in sperm cells. There are, however, many antioxidants in the body which deactivate free radicals and act as inhibitors of the oxidation process, even at relatively low concentrations and thus have diverse physiological roles. What are the effects of HBs on antioxidants in sperm cells In the present study, the TAC of sperm cells was investigated and the results showed that TAC levels in sperm cells exposed to HBs declined with increasing concentrations of HBs. It indicated that HBs exposure was not only able to induce ROS generation and lipid peroxidation but also reduce antioxidant capacity in sperm cells, resulting in oxidative stress, an imbalance between the production and manifestation of ROS and a biological system’s ability to readily detoxify the reactive intermediates, 22694778 leading to sperm dysfunctions. activity is also an early indicator of apoptosis. The caspases are a family of proteins within the cell as inactive pro-forms which can be cleaved to form active enzymes following the induction of apoptosis. In the present study, a possible link between HBs exposure and caspases-3, -8 and -9 activations in sperm cells was investigated. The results showed that there were a markedly increase of caspases-3, -8 and -9 positive cells in the exposed cells when compared with the unexposed cells, indicating that HBs exposure was able to induce caspases-3, -8 and -9 activation in sperm cells. The effects of HBs exposure on caspases-3, -8 and -9 activations in sperm cells also exhibited dose dependence. DNA fragmentation is commonly considered as the key feature of apoptosis in many cell types. In the present study, we detected apoptosis in sperm cells after 3 h of exposure to 25 mg/ml of HBs, the average rate of TUNEL positive cells was significantly elevated as compared to the control. In addition, the effects of HBs exposure on oxidative DNA damage in sperm cells also showed dose dependence. Oxidative stress, loss of MMP and apoptosis caused sperm dysfunctions Since the mitochondria of the sperm midpiece generate energy to support motility, the state of sperm MMP is a useful indicator of functional impairments on the reproductive system. It was well documented that a high correlation between poor sperm mitochondrial functions and diminished motility and reduced fertility. In our previous study, it was detected that HBs caused sperm MMP loss to reduce sperm motility, leading to the death of sperm cells and a lower fertilization rate and a lower fertilizing index. The present study showed t