嗜水气单胞菌亚单位疫苗的研制

Studies on the Subunit Vaccine of Aeromonas hydrophilia

首先提纯嗜水气单胞菌Ｊ－１株的外毒素一ＨＥＣ毒素和脂多糖，进而将脂多糖脱去类脂Ａ，再用ＥＤＣ法将ＨＥＣ毒素与多糖偶联。偶联物经双抗体夹心ＥＬＩＳＡ和ＳｅｐｈａｄｅｘＧ－２００层析鉴定确认，ＨＥＣ毒素与多糖的偶联比为１：１．３。偶联物作为亚单位苗，对小鼠和鲫鱼均无毒性，能诱导免疫小鼠和鲫鱼产生坚强的保护，对同源菌株的攻击保护率，小鼠１００％，鲫鱼８３％。与嗜水气单胞菌的全菌苗和毒素苗相比，亚单位苗诱导的抗体出现早，滴度高，持续时间长。

Lipopolysaccharide (LPS)extracted from Aeromonas hydrophilia J-1strain was detoxified and then conjugated to HEC-toxin purified from the extracellularproducts of the same germs.The conjugates were characterized by sandwich-ELISA andchromatography of Sephadex G-200.As a subbunit vaccine(5V),the conjugates wereadministered intraperitoneally into mice and crucian carp(Carassius carassius)at thedose of 1 μg and 10 μg,respectively.One month later,carp were challenged with homo-geneous strain by intraperitoneal injection,the results showed good protection.Afterbooster,the mice were protected very well against challenge.An enhanced and pro-longed antibody response was confirmed by microagglutination test and HEC～toxinhemolytic inhibition test,in comparison with the formalinized whole cell bacterin(WCB)immersed control fish.