TAP-independent selection of CD8+ intestinal intraepithelial lymphocytes.

Abstract

Intestinal intraepithelial lymphocytes (IEL) are mostly CD8 single positive T cells. IEL with a TCR-alpha(beta) that are CD8 single positive are absent from beta(2)-microglobulin (beta(2)m)-deficient mice, consistent with the idea that these IEL, like other TCR-alpha(beta)+, CD8+ T cells, require class I molecules for positive selection. In contrast, here we show that substantial numbers of TCR-alpha(beta)+, CD8 single positive IEL are present in mice deficient for the transporter associated with Ag processing 1 (TAP 1) gene, although T cells with this phenotype are absent from thymus, spleen, and lymph nodes of these same mice. The majority of TCR-alpha(beta)+, CD8 single positive IEL in TAP-deficient mice expresses CD8 molecules composed of alpha(alpha) homodimers and they express a diverse set of V(beta) gene segments. In addition, the number of TCR-alpha(beta)+, CD4/CD8 double positive IEL is decreased in beta(2)m-deficient mice but not in TAP-deficient mice. The dependence of the two TCR-alpha(beta)+ IEL populations that express CD8alpha(alpha) homodimers on beta(2)m as opposed to TAP molecules is striking. It suggests that TAP-independent but beta(2)m-requiring nonclassical class I molecules expressed by cells in the intestine, such as the thymus leukemia Ag and CD1, could play a pivotal role in the development and/or the accumulation of major subpopulations of TCR-alpha(beta)+ IEL.

• Authors: B C Sydora, L Brossay, A Hagenbaugh, M Kronenberg, H Cheroutre
• Journal: Journal of immunology (Baltimore, Md. : 1950) (J Immunol) Vol. 156 Issue 11 Pg. 4209-16 (Jun 01 1996) ISSN: 0022-1767 [Print] United States
• PMID: 8666789 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• ATP Binding Cassette Transporter, Subfamily B, Member 2
• ATP-Binding Cassette Transporters
• CD4 Antigens
• CD8 Antigens
• Histocompatibility Antigens Class I
• Receptors, Antigen, T-Cell, alpha-beta
• TAP1 protein, human
• Tap1 protein, mouse
• beta 2-Microglobulin

Topics

• ATP Binding Cassette Transporter, Subfamily B, Member 2
• ATP-Binding Cassette Transporters (genetics, metabolism)
• Animals
• CD4 Antigens (metabolism)
• CD4-Positive T-Lymphocytes (immunology, metabolism)
• CD8 Antigens (metabolism)
• CD8-Positive T-Lymphocytes (immunology, metabolism)
• Epithelial Cells
• Epithelium (immunology)
• Histocompatibility Antigens Class I (metabolism)
• Intestines (cytology, immunology)
• Mice
• Mice, Inbred C57BL
• Mice, Mutant Strains
• Receptors, Antigen, T-Cell, alpha-beta (metabolism)
• T-Lymphocyte Subsets (immunology, metabolism)
• beta 2-Microglobulin (deficiency, genetics)