IL-9是一种多效细胞因子，与多种过程相关，包括抗肿瘤免疫力、过敏病理诱导以及对蠕虫感染的免疫反应，在蠕虫排出过程中起到了重要作用。在Nippostrongylus brasiliensis感染的小鼠模型中，IL-9主要由CD4+ T淋巴细胞和存在于肺部、小肠和引流淋巴结的固有淋巴细胞产生。考虑到侵入细胞内的IL-9染色以及对小肠造血细胞的分离困难等技术难点，急需建立一种全面且简单的协议来分析该模型中不同淋巴和非淋巴组织中IL-9的表达情况。本协议描述了在感染过程中在肺和小肠中的CD4+ T细胞和固有淋巴细胞产生的IL-9的动力学，它们是N. brasiliensis的主要靶器官以及在中胸和肠系膜淋巴结中的表达情况。另外，它详细说明了依赖于细胞类型和感兴趣的器官所需的幼虫数量。本协议旨在帮助标准化检测，以节省时间和资源，并为在N. brasiliensis感染模型中专注于特定的细胞、器官和疾病阶段提供机会。

IL-9 is a pleiotropic cytokine associated with various processes, including antitumor immunity, induction of allergic pathologies, and the immune response against helminth infections, where it plays an important role in the expulsion of the parasite. In a murine model of Nippostrongylus brasiliensis infection, IL-9 is produced mainly by CD4+ T lymphocytes and innate lymphoid cells found in the lung, small intestine, and draining lymph nodes. Given the technical difficulties involved in the intracellular staining of IL-9, as well as the complexity of isolating hematopoietic cells from the small intestine upon infection, there is a pressing need for a comprehensive but straightforward protocol to analyze the expression of IL-9 in different lymphoid and non-lymphoid tissues in this model. The protocol described here outlines the kinetics of IL-9 produced by CD4+ T cells and innate lymphoid cells in the lung and small intestine, the main organs targeted by N. brasiliensis, as well as in the mediastinal and mesenteric lymph nodes, throughout the infection. In addition, it details the number of larvae needed for infection, depending on the cell type and organ of interest. This protocol aims to assist in the standardization of assays to save time and resources by offering the opportunity to focus on the specific cells, organs, and disease stages of interest in the N. brasiliensis infection model.