HOST RESPONSE TO HELICOBACTER PYLORI INFECTION

幽门螺杆菌引起的胃炎是当今世界上最常见的慢性感染。 它已被IARC（WHO）列为I类人类致癌物。 显然，只有一小部分感染人群会发展成胃癌。 然而，这种肿瘤是世界上第二常见的。 在美国，某些群体显示出更高的风险，特别是非洲裔美国人，西班牙裔美国人，亚裔美国人以及来自俄罗斯和东欧的移民。 该应用解决了H.幽门螺杆菌感染，在某些受试者中导致胃癌发生，而在另一些受试者中则不会。 中心假设是，感染结果的二分法是由免疫力驱动的。 拟议的小额赠款申请将使人们有可能进行一项可行性研究，以确定是否有可能对这一假设进行更明确的检验。 我们将集中在从外周血和胃粘膜的淋巴细胞研究细胞介导的免疫反应。 两个主要的比较将完成：A）在哥伦比亚H。将生活在纳里奥的胃癌风险非常高的幽门螺杆菌感染受试者与生活在沿海城市卡塔赫纳的胃癌风险非常低的受试者进行比较。B）在新奥尔良，将诊断为多灶性萎缩性胃炎（MAG）（一种癌症前体病变）的受试者与非萎缩性胃炎（弥漫性胃窦炎或DAG）的受试者进行比较，后者与胃癌风险增加无关。 将进行一系列完整的免疫学试验，以探索T淋巴细胞辅助细胞应答（Th1 vs. Th2）的细胞因子特征在对比人群中是否不同。 如果获得批准，该申请将使我们能够收集所需的材料，并补充病理部门的其他资源，以便在我们的实验室进行测试。

Gastritis due to Helicobacter Pylori is the most common chronic infection in the world today. It has been classified by IARC (WHO) as a Class I human carcinogen. Obviously only a very small portion of the infected population develops gastric cancer. This neoplasia, however, is the second most frequent in the world. In the United States, certain groups display higher risk, especially African Americans, Hispanics, Asian Americans and immigrants from Russia and Eastern Europe. This application addresses the question of different outcomes of H. Pylori infection, which in some subjects leads to gastric carcinogenesis and in others does not. The central hypothesis is that the dichotomy in outcome of the infection is driven by immunologic forces. The proposed small grant application will make it possible to conduct a feasibility study which will determine if a more definitive test of the hypothesis is possible. We will be focused on the cellular-mediated immune response studied in lymphocytes from the peripheral blood and from the gastric mucosa. Two major comparisons will be done: A) In Colombia H. pylori infected subjects living in Nari$o, at very high gastric cancer risk, will be compared with infected subjects living in the coastal city of Cartagena, at very low risk. b) In New Orleans, subjects diagnosed with multiphocal atrophic gastritis (MAG), a cancer precursor lesion, will be compared with subjects with non-atrophic gastritis (diffuse antral gastritis or DAG), which is not associated with increased gastric cancer risk. A full battery of immunologic tests will be carried out to explore if the cytokines characteristic of the T-lymphocyte helper cells responses (Th1 vs. Th2) are different in the contrasting populations. If approved, this application will make it possible to collect the material needed and complement other resources of the department of Pathology to conduct the tests in our laboratories.