Ohteki T, Abo T, Seki S, Kobata T, Yagita H, Okumura K, Kumagai K
Department of Microbiology, Tohoku University School of Dentistry, Sendai and Department of Immunology, Japan.
Eur J Immunol. 1991 Jul;21(7):1733-40. doi: 10.1002/eji.1830210722.
gamma/delta T lymphocytes residing in the liver of mice were systematically characterized with respect to their age-related variation, phenotype and V gene segment usage of gamma/delta T cell receptor (TcR). Previous human and murine studies have shown that a high proportion of gamma/delta T cells reside in the liver and that such liver gamma/delta T cells have lymphoblastic morphology and can spontaneously proliferate in vitro. In the present study, a predominant appearance of gamma/delta T cells (up to 23% among CD3+ cells) in the liver was confirmed in 4-week old mice of various strains. gamma/delta T cells in the liver preferentially co-expressed CD8 antigens, whereas the vast majority of gamma/delta T cells in the spleen lacked the CD8 antigens. The identification of gamma/delta T cells in various lymphoid and non-lymphoid organs also revealed the liver to be one of the organs where gamma/delta T cell are most abundant. The level of such liver gamma/delta T cells showed a clear age-related variation. In the fetal stage and just after birth, gamma/delta T cells were not detectable in the liver (less than 0.2%). However, a significantly higher percentage of gamma/delta T cells among both the total population of mononuclear cells and CD3+ cells was detected in the liver of young 2- to 8-week-old mice; this percentage subsequently declined. As the total number of liver mononuclear cells increased in aged mice, the absolute number of liver gamma/delta T cells also increased as a function of age. V gene segment usage analysis by the polymerase chain reaction method demonstrated that V gamma 1 or V gamma 2/V delta 6 were preferentially used by liver gamma/delta T cells. The age-related increase of gamma/delta T cells was more prominent in the liver of athymic nude mice, and such gamma/delta T cells highly co-expressed the CD8 antigens and also utilized the V gamma 1 or V gamma 2/V delta 6 for gamma/delta Tcr. The predominant appearance of unique gamma/delta T cells in the liver, which was inversely related to the existence of the thymus, indicates that these gamma/delta T cells may differentiate extrathymically in the liver.
对小鼠肝脏中的γ/δ T淋巴细胞，就其与年龄相关的变化、表型以及γ/δ T细胞受体（TcR）的V基因片段使用情况进行了系统表征。先前的人类和小鼠研究表明，高比例的γ/δ T细胞存在于肝脏中，且此类肝脏γ/δ T细胞具有淋巴细胞形态，能够在体外自发增殖。在本研究中，在4周龄的各种品系小鼠肝脏中证实了γ/δ T细胞的显著存在（在CD3+细胞中高达23%）。肝脏中的γ/δ T细胞优先共表达CD8抗原，而脾脏中绝大多数γ/δ T细胞缺乏CD8抗原。对各种淋巴和非淋巴器官中γ/δ T细胞的鉴定还表明，肝脏是γ/δ T细胞最为丰富的器官之一。此类肝脏γ/δ T细胞的水平呈现出明显的与年龄相关的变化。在胎儿期及出生后不久，肝脏中无法检测到γ/δ T细胞（低于0.2%）。然而，在2至8周龄的幼鼠肝脏中，单核细胞总数和CD3+细胞中γ/δ T细胞的百分比显著更高；该百分比随后下降。随着老年小鼠肝脏单核细胞总数增加，肝脏γ/δ T细胞的绝对数量也随年龄增加。通过聚合酶链反应方法进行的V基因片段使用分析表明，肝脏γ/δ T细胞优先使用Vγ1或Vγ2/Vδ6。γ/δ T细胞与年龄相关的增加在无胸腺裸鼠肝脏中更为显著，且此类γ/δ T细胞高度共表达CD8抗原，并且γ/δ Tcr也使用Vγ1或Vγ2/Vδ6。肝脏中独特γ/δ T细胞的显著存在与胸腺的存在呈负相关，这表明这些γ/δ T细胞可能在肝脏中进行胸腺外分化。
