以近江牡蛎全脏器为原料提取近江牡蛎糖胺聚糖，对其理化性质和免疫调节活性进行研究。采用柱层析法分离纯化近江牡蛎糖胺聚糖得到纯化级分；用高效液相色谱（HPLC）、红外光谱（IR）分析其理化性质；采用小鼠体内注射环磷酰胺（CTX）法建立免疫抑制动物模型，测试其对小鼠的非特异性免疫、体液免疫的影响；采用噻唑蓝（MTT）法检测细胞免疫和自然杀伤细胞（NK细胞）活性；采用ELISA法检测肿瘤坏死因子TNF-α、干扰素IFN-γ、小鼠白细胞介素IL-2的含量；Griess法测定NO含量。结果表明近江牡蛎糖胺聚糖纯化级分CGIa、CGIIa是由糖醛酸、氨基葡萄糖按一定比例构成，含有硫酸基，相对分子量分别为5.17×105 Da、2.64×105 Da，IR分析显示，CGIa和CGIIa都具有糖胺聚糖的特征吸收。牡蛎糖胺聚糖对正常小鼠免疫器官指数、抗体生成数和血清溶血素、细胞免疫、单核巨噬细胞、NK细胞杀伤活性的影响均为阳性，表明其具有免疫增强功能。CGIa和CGIIa能促进正常小鼠免疫细胞分泌TNF-α、IFN-γ、IL-2和NO细胞因子。免疫功能的增强可能是通过促进细胞因子的分泌实现的。

Glycosaminoglycans were extracted from the jinjiang oyster, Crassostrea rivularis, and their physicochemical properties and immunomodulatory activities were studied. Column chromatography was used to obtain a purified fraction of glycosaminoglycans, while high-performance liquid chromatography (HPLC) and infrared spectroscopy (IR) were used to study their physicochemical properties. An immunosuppressed animal model was established by injecting cyclophosphamide (CTX) in mice and the effects of Jinjiang oyster Crassostrea rivularis-derived glycosaminoglycans on the nonspecific immunity and humoral immunity of mice were studied. The activity of immune cells and natural killer (NK) cells was evaluated by the MTT assay. Tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-2 levels in mice were measured by enzyme-linked immunosorbent assay (ELISA). The level of nitric oxide (NO) was determined by Griess assay. The results showed that CGIa and CGIIa from the purified fraction of glycosaminoglycans consisted of uronic acid and glucosamine in a certain proportion, with relative molecular weights of 5.17 × 105 and 2.64 × 105 Da, respectively, in addition to sulfate groups. IR analysis showed that CGIa and CGIIa showed characteristic IR absorption profiles of glycosaminoglycans. The results of tests for glycosaminoglycans effects on the immune organ index, antibody production number, serum hemolysin level, cellular immunity, mononuclear macrophage, killing activity of NK cells in normal mice, were all positive, indicating that Jinjiang oyster Crassostrea rivularis glycosaminoglycans enhances immune function. CGIa and CGIIa also stimulated immune cells in normal mice to secrete cytokines including TNF-α, IFN-γ, IL-2, and NO. Enhanced immune function may be achieved by promoting the secretion of cytokines.

广东省海洋渔业科技推广专项(A201008I02)