CD 103

Sources/Clones
Biogenex (2G5), Coulter (2G5), Dako (Ber-ACT8), Immunotech (2G5) and Serotec (295.1).

Fixation/Preparation
The antibodies are mainly immunoreactive in cryostat sections of fresh-frozen tissue. Immunoreactivity in fixed paraffin-embedded sections has not been reported.

Background
The antibody to CD 103, also known as antihuman mucosal lymphocyte 1 antigen (HML-1), recognizes a T-cell-associated trimeric protein of 150, 125 and 105 kD (Falini et al, 1991), which is expressed on 95% of intraepithelial lymphocytes and only on 1-2% of peripheral blood lymphocytes (Spencer et al, 1988; Kruschwitz et al, 1991). CD 103 (a E-integrin) antigen is part of the family ofb 7 integrins on human mucosal lymphocytes which play a specific role in mucosal localization or adhesion (Parker et al, 1992). CD 103 is a receptor for the epithelial cell-specific ligand E-cadherin and is expressed by a major subset of CD 3+, CD 8+, CD 4- lymphocytes present in the intestinal mucosa. About 40% of isolated intestinal lamina propria lymphocytes (LPL) expressed HML-1, the majority being CD 8+.Virtually all LPL expressed CD 45RO whereas only about 50% were CD 29+, a percentage similar to that in peripheral blood lymphocytes. HML-1 + cells were almost exclusively CD 45RA- and the in vitro expression of HML-1 was inducible on T-cells by mitogen (Schieferdecker et al, 1990).

Applications
Antibodies to CD 103 are used for the diagnosis of intestinal T-cell lymphoma (Schmitt-Graff et al, 1996). CD 103 has been found to be a useful marker of B-cell hairy cell leukemia which shows strong reactivity for CD 22, CD 25, CD 103, DBA.44 as well as immunoglobulin light-chain restriction (Harris et al, 1994; Cordone et al, 1995). The antigen may be occasionally expressed by some B-cell lymphomas (Moller et al, 1990) and has also been demonstrated in T-lymphoblastic lymphoma (Falini et al, 1991).

Comments
Current diagnostic applications of antibodies to CD 103 are restricted by their immunoreactivity only in fresh cell preparations and cryostat sections.

References
•Cordone I, Annino L, Masi S et al 1995. Diagnostic relevance of peripheral blood immunocytochemistry in hairy cell leukemia. Journal of Clinical Pathology; 48: 955-960.

•Falini B, Flenghi L, Fagioli M et al 1991. Expression of the intestinal T-lymphocyte associated molecule HML-1; analysis of 75 non-Hodgkin's lymphomas and description of the first HML-1 positive T-lymphoblastic lymphoma. Histopathology; 18: 421-426.

•Harris NL, Jaffe ES. Stein H et al 1994. A revised European-American classification of lymphoid neoplasms: a proposal from the International Lymphoma Study Group. Blood; 84: 1361-1392.

•Kruschwitz M, Fritzsche G, Schwarting M et al 1991. Ber-ACT8: new monoclonal antibody to the mucosa lymphocyte antigen. Journal of Clinical Pathology; 44: 636-645.

•Moller P, Mielke B, Moldenhauer G 1990. Monoclonal antibody HML-1, a marker for intraepithelial T cells and lymphomas derived thereof, also recognizes hairy cell leukemia and some B cell lymphomas.

•American Journal of Pathology; 136: 509-512. cells and lymphomas derived thereof, also recognizes hairy cell leukemia and some B cell lymphomas.

•Parker CM, Cepek KL, Russell GJ et al 1992. A family of beta 7 integrins on human mucosal lymphocytes. Proceedings of the National Academy of Sciences USA; 89: 1924-1928.

•Schieferdecker HL, Ullrich R, Weiss-Breckwoldt AN et al 1990. The HML-1 antigen of interstinal lymphocytes is an activation antigen. Journal of Immunology; 144: 2541-2549.

•Schmitt-Graff A, Hummel M, Zemlin M et al 1996. Intestinal T-cell lymphoma: a reassessment of cytomorphological and phenotypic features in relation to patterns of small bowel remodelling. Virchows Archives; 429: 27-36.

•Spencer J, Cerf-Bensussan N, Jarry A et al 1988. Enteropathy associated T cell lymphoma (malignant histiocytosis of the intestine) is recognized by a monoclonal antibody (HML1) that defines a membrane molecule on human lymphocytes. American Journal of Pathology; 132: 1-5.

Bibliografía
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.