Ⅱ、Ⅳ、Ⅴ、Ⅹ型磷脂酶A_2 mRNA在大鼠淋巴器官中的分布

Distribution of Phospholipase A_2 Types Ⅱ,Ⅳ,Ⅴ and Ⅹ mRNA in Rat Lymphoid Organs

目的探讨Ⅱ、Ⅳ、Ⅴ、Ⅹ型磷脂酶A2(PLA2)mRNA在正常大鼠淋巴器官中的分布情况,了解各型PLA2在细菌感染所致的免疫反应中可能发挥的作用。方法从大鼠的淋巴器官骨髓、胸腺、淋巴结和脾的组织匀浆中提取总RNA,合成第1链cDNA,利用PCR扩增上述各型PLA2DNA,PCR产物经2%琼脂糖凝胶电泳检测。结果在大鼠淋巴器官中均能检测到Ⅱ、Ⅳ型PLA2mRNA,Ⅱ型PLA2mRNA的含量比Ⅳ型PLA2mRNA高;只在脾中检测到Ⅴ型PLA2mRNA;在各淋巴器官中均未检测到Ⅹ型PLA2mRNA。结论实验表明,Ⅱ型和Ⅳ型PLA2广泛存在于中枢和外周淋巴器官中,含量丰富,在宿主防御细菌感染的过程中,除了参与先天免疫外,很可能参与获得性免疫反应;Ⅴ型PLA2mRNA存在于脾脏中,也可能参与获得性免疫反应,但不如Ⅱ型和Ⅳ型PLA2重要。

OBJECTIVE To investigate the distribution of phospholipase A2 （PLA2） types Ⅱ, Ⅳ, Ⅴ and Ⅹ mRNA in rat lymphoid organs, including bone marrow, thymus, lymph node and spleen, in order to increase our knowledge in their possible role in bacterial infection. METHODS The total RNA was extracted from lymphoid organs homogenate. Then the first-strand cDNA was synthesized and PLA2 DNA was amplified by PCR. The PCR products were analyzed by 2% agarose gel electrophoresis. RESULTS PLA2 types Ⅱ and Ⅳ mRNA were detectable in bone marrow, thymus, lymph node and spleen. But the content of PLA2 type Ⅱ mRNA was richer than type Ⅳ. PLA2 types Ⅴ mRNA was only detectable in spleen. PLA2 types Ⅹ mRNA was not detectable in rat lymphoid organs. CONCLUSIONS PLA2 types Ⅱ and Ⅳ mRNA is found in both central and peripheral lymphoid organs. In the process of host defense against bacterial infection, besides the role in innate immunity, the two types of PLA2 may take part in adaptive immunity. PLA2 type Ⅴ mRNA is only found in spleen and may play a role in adaptive immunity, too. However, it may not important as types PLA2 Ⅱ and Ⅳ.