Do T cells have CD1?

2.1. CD1 molecules are expressed on thymocytes. They are absent from mature peripheral blood T cells, but their cytoplasmic expression has been observed in activated T lymphocytes. High levels of CD1a and, to a lesser degree, of CD1b and CD1c are present on the Langerhans cells.

What are CD1 restricted T cells?

CD1-restricted T cells that are specific for the foreign microbial lipids are stimulated to carry out effector functions, including the secretion of cytolytic granules containing perforin and granulysin, which lyse the infected cells and have direct antimicrobial effects, respectively, and the production of cytokines …

What are CD1 cells?

CD1 (cluster of differentiation 1) is a family of glycoproteins expressed on the surface of various human antigen-presenting cells. They are related to the class I MHC molecules, and are involved in the presentation of lipid antigens to T cells.

How are CD1 antigens presented to T cells?

In this Review, we describe the pathway of CD1 antigen presentation, including the delivery, processing, loading and presentation of lipid antigens to T cells.

How are NKT cells activated by CD1 antigen?

The injection of mice with human melanoma cells or GD3-loaded dendritic cells (DCs) also stimulates a CD1d-restricted NKT-cell response 22. Recently, iGb3 (isoglobotrihexosylceramide), a member of the globo/isoglobo-series glycosphingolipids ( Box 1 ), was found to activate i NKT cells in vitro 10, 23.

How are lipids presented in the CD1 molecule?

The lipid antigens presented by CD1 molecules include a broad array of classes, ranging from foreign lipids that are unique to specific microorganisms to common mammalian self lipids. Foreign lipid antigens. Many of the unique lipids found in Mycobacterium tuberculosis can be presented by CD1a, CD1b and CD1c to activate clonally diverse T cells.

How does the immune system recognize lipid antigens?

However, the discovery of MHC-class-I-like CD1 antigen-presentation molecules now explains how the immune system also recognizes the abundant and diverse universe of lipid-containing antigens. The CD1 molecules bind and present amphipathic lipid antigens for recognition by T-cell receptors.