       Document 0600
 DOCN  M9620600
 TI    Mac1 discriminates unusual CD4-CD8- double-negative T cells bearing
       alpha beta antigen receptor from conventional ones with either CD4 or
       CD8 in murine lung.
 DT    9602
 AU    Kawakami K; Teruya K; Tohyama M; Kudeken N; Yonamine Y; Saito A; First
       Department of Internal Medicine, Faculty of Medicine,; University of the
       Ryukyus, Okinawa, Japan.
 SO    Immunol Lett. 1995 May;46(1-2):143-52. Unique Identifier : AIDSLINE
       MED/96078168
 AB    Pulmonary intraparenchymal leukocytes were purified from normal mice. By
       flow cytometry, 20-30% of the lymphocytes were positive for the
       expression of Mac1, a cell-surface antigen largely restricted to
       macrophages, neutrophils and natural killer (NK) cells. Sorted Mac1+
       lung lymphocytes were large and had abundant cytoplasm with few
       azurophilic granules. Because Mac1+ lymphocytes did not contain any
       asiallo GM1+ cells, they are not likely to be NK cells. By a two-color
       flow cytometric analysis, Mac1+ lymphocytes were demonstrated to be
       TCR-alpha beta intermediate+, TCR-gamma delta-, CD3intermediate+, CD4-,
       CD8-, Thy1-, CD5-, and B220-. These Mac1+ alpha beta T cells were not
       found in other organs such as spleen, thymus, liver, bone marrow and
       intestine of mice uninfected and infected with Mycobacterium bovis BCG.
       There was a considerable population of this unusual subset of alpha beta
       T cells in the lungs of congenitally athymic nude mice. In the Mac1+
       alpha beta T-cell population, the proportions of V beta 8+ T cells and
       of forbidden T-cell clones expressing V beta 6 TCR were not much
       different from that in the conventional T-cell population. These results
       indicated that extrathymically developed alpha beta T cells reside in
       considerable proportions in the lung and that Mac1 clearly discriminates
       these cells from conventional ones. Interestingly, the proportion of
       these cells increased in the lungs of mice infected with M. bovis BCG,
       which raises a possibility that these cells may play some role in the
       host defense against mycobacterial infection.
 DE    Animal  CD4-Positive T-Lymphocytes/*IMMUNOLOGY  CD8-Positive
       T-Lymphocytes/*IMMUNOLOGY  Immunophenotyping
       Lung/CYTOLOGY/IMMUNOLOGY/*METABOLISM  Macrophage-1 Antigen/*CHEMISTRY
       Male  Mice  Mice, Inbred BALB C  Mice, Inbred DBA  Mice, Nude
       Mycobacterium bovis/IMMUNOLOGY  Organ Specificity/IMMUNOLOGY  Receptors,
       Antigen, T-Cell, alpha-beta/BIOSYNTHESIS/*IMMUNOLOGY  T-Lymphocyte
       Subsets/*IMMUNOLOGY  Tuberculosis/IMMUNOLOGY  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

