STUDIES OF HUMAN T-HELPER CELL TYPE 1 AND TYPE 2 CYTOKINE RESPONSES

T辅助细胞已被划分为不同的子集 它们分泌的细胞因子。Tho细胞分泌IL-2、IL-4和IFN-γ；TH1细胞 分泌IL-2和IFN-γ；TH2细胞分泌IL-4。易感性 某些传染病已被证明依赖于 诱导出优势类型的TH细胞。有一些证据表明 HIV-1感染的进展与偏向TH2细胞有关。 因此，用于HIV-1感染的疫苗如果能诱导抗-1抗体，则可能是有利的。 通过招募Th1而不是Th2细胞来免疫艾滋病毒。B.流产已被 显示能在小鼠体内诱导TH1细胞。因为流产杆菌也能刺激 人类B细胞的T非依赖性，我们一直将其作为一种 作为疫苗的HIV-1蛋白和多肽的可能载体。确实是 因此，有兴趣确定流产杆菌对 人类T细胞。通过外周血传代纯化人T细胞 尼龙羊毛上的单个核细胞，然后是Percoll梯度 离心法。小的静息T细胞被刺激在存在的 B.流产，并显示能分泌干扰素γ和白介素2，但不分泌白介素4。同样， 从这些细胞中提取的RNA的聚合酶链式反应显示，流产杆菌诱导了 IL-2、IL-2、IL-2R m RNA，但不表达IL-4 m RNA。IFNGamma的来源 不是因为磁珠去除NK细胞而污染NK细胞 细胞对预后没有影响，而浓缩的NK细胞耗尽了T 细胞对流产杆菌无反应。这些结果表明，B. 流产可以刺激人类T细胞的TH1反应，因此可能是 作为HIV-1感染者的携带者是有益的。

T helper cells have been divided into different subsets based on the cytokines they secrete. THO cells secrete IL2, IL4 and IFNgamma; TH1 cells secrete IL2 and IFNgamma; and TH2 cells secrete IL4. Susceptibility to certain infectious diseases has been shown to be dependent on the predominant type of TH cell induced. There is some evidence that progression of HIV-1 infection is associated with a bias towards TH2 cells. Thus, vaccines for HIV-1 infection may be advantageous if they induce anti- HIV immunity by recruiting TH1 rather than TH2 cells. B. abortus has been shown to induce TH1 cells in mice. Since B. abortus can also stimulate human B cells in a T-independent manner we have been studying it as a possible carrier for HIV-1 proteins and peptides as a vaccine. It was therefore of interest to determine what effect B. abortus would have on human T cells. Human T cells were purified by passage of peripheral blood mononuclear cells over nylon wool followed by percoll gradient centrifugation. Small resting T cells were stimulated in the presence of B. abortus and shown to secrete IFNgamma and IL2, but not IL4. Similarly, PCR amplification of RNA from these cells showed that B. abortus induced IFNgamma, IL2 and IL2R mRNA but no IL4 mRNA. The source of the IFNgamma was not from contaminating NK cells because magnetic bead removal of NK cells had no effect on the outcome, and enriched NK cells depleted of T cells did not respond to B. abortus. These results indicate that B. abortus can stimulate TH1 responses from human T cells, and as such may be beneficial as a carrier for persons infected with HIV-1.