T-Cell Development PDF
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This document explains the process of T-cell development within the immune system. It describes how immature T-cells are produced and how they mature via positive and negative selection mechanisms. The document also highlights the role of various proteins and cell types in this process.
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How do T-cells develop? Immature T-cells are produced in the bone marrow Thymic epithelial cells releases chemokines to guide them to it (chemotaxis) This stimulates genes in the T-cell (RAG1, RAG2) RAG1 and RAG2 activate recombination and TCR is generated that can bind to antibodie...
How do T-cells develop? Immature T-cells are produced in the bone marrow Thymic epithelial cells releases chemokines to guide them to it (chemotaxis) This stimulates genes in the T-cell (RAG1, RAG2) RAG1 and RAG2 activate recombination and TCR is generated that can bind to antibodies CD proteins are also produced ○ CD8 binds to MHC1 ○ CD4 binds to MHC2 ○ MHCs are expressed on the Thymic cells ○ Positive Selection: T-cells appropriately recognized MHCs Will undergo apoptosis if it fails MHCs also have peptides (tacos) ○ Don't want TCRs to recognize self-antigens/peptides (Negative Selection) ○ Will undergo apoptosis if it recognizes it If T-cell binds to MHC1 it will downregulate genes that produces CD4 and vice versa ○ Upregulation of CD4: becomes a Helper T-cell ○ Upregulation of CD8: becomes Cytotoxic T-cell ○ Some of both types will become Regulatory T-cells (helps prevent autoimmune diseases)
