Analyzing human CD4+ T cells activated in response to macrophages infected with Mycobacterium tuberculosis.

M1- and M2-like macrophages infected with Mycobacterium tuberculosis (Mtb) have been found to differ in their capacity to elicit memory CD4+ T cell activation. Here, we present a protocol to quantify and isolate the subset of human memory CD4+ T cells activated in response to autologous monocyte-derived macrophages (MDMs) infected with virulent Mtb. We describe steps for CD14+ monocyte isolation, generating MDMs, culturing Mtb and infection of macrophages, and identifying activated CD4+ T cells by flow cytometry. For complete details on the use and execution of this protocol, please refer to Gail et al.1.