Proliferating intestinal gamma / parallel T cells recirculate rapidly and are a major source of the gamma / parallel T cell pool in the peripheral blood

• Published in: European journal of immunology Vol. 33; no. 6; pp. 1649 - 1656
• Main Authors: Thielke, K-H, Hoffmann-Moujahid, A, Weisser, C, Waldkirch, E, Pabst, R, Holtmeier, W, Rothkoetter, HJ
• Format: Journal Article
• Language: English
• Published: 01.01.2003
• ISSN: 0014-2980
• DOI: 10.1002/eji.200323442

The proliferation, recirculation and repertoire of gut-derived gamma / parallel T cells were studied in pigs in vivo. Proliferating gamma / parallel T cells (detected by BrdU labeling) are present in all intestinal compartments. In the gut lymph ~0.5% of all gamma / parallel T cells were proliferating. These gut-derived BrdU super(+) gamma / parallel T cells re-enter the intestinal tissues, and re-appear in the intestinal lymph far more often than other cells: about 22% of i.v.-injected BrdU super(+) gamma / parallel T cells were recovered again from the intestinal lymph within 72 h (compare with BrdU super(+) B cells 2%, and other BrdU super(+) T cells 10%). The contribution of the gut to the migrating gamma / parallel T cell pool in the blood became obvious: the proportion of BrdU super(+) gamma / parallel T cells was three-times larger in control versus cannulated pigs. In 9-month-old pigs, clonally expanded T cells were identified in the intestine by complementarity-determining region 3 spectratyping of TCR- parallel transcripts. Such expansions were not visible in the blood or intestinal lymph. The distribution of gamma / parallel T cells within the intestinal tract is likely to depend to a large degree on the proliferation and the migratory properties of these cells which are different to those of alpha / beta T cells and B lymphocytes.