where are t lymphocytes located in lymph nodes
Lymph node Thin reticular fibers of reticular connective tissue, and elastin form a supporting meshwork called a reticulin inside the node. B cells are mainly found in the outer (superficial cortex) where they are clustered together as follicular B cells in lymphoid follicles and the T cells are mainly in the paracortex.[6] The lymph node is divided into compartments called lymph nodules (or lobules) each consisting of a cortical region of combined follicle B cells, a paracortical region of T cells, and a basal part of the nodule in the medulla.[7]
T cell A T cell, or T lymphocyte, is a type of lymphocyte (a subtype of white blood cell) that plays a central role in cell-mediated immunity. T cells can be distinguished from other lymphocytes, such as B cells and natural killer cells, by the presence of a T-cell receptor on the cell surface. They are called T cells because they mature in the thymus from thymocytes[1] (although some also mature in the tonsils[2]). The several subsets of T cells each have a distinct function. The majority of human T cells rearrange their alpha and beta chains on the cell receptor and are termed alpha beta T cells (αβ T cells) and are part of the adaptive immune system. Specialized gamma delta T cells, (a small minority of T cells in the human body, more frequent in ruminants), have invariant T-cell receptors with limited diversity, that can effectively present antigens to other T cells[3] and are considered to be part of the innate immune system.
Small intestine Absorption of the majority of nutrients takes place in the jejunum, with the following notable exceptions:
T cell About 98% of thymocytes die during the development processes in the thymus by failing either positive selection or negative selection, whereas the other 2% survive and leave the thymus to become mature immunocompetent T cells. Increasing evidence indicates microRNAs, which are small noncoding regulatory RNAs, could impact the clonal selection process during thymic development. For example, miR-181a was found to play a role in the positive selection of T lymphocytes.[31]