Unusual T cell populations in adult murine bone marrow. Prevalence of CD3+CD4-CD8- and alpha beta TCR+NK1.1+ cells.
Unusual T cell populations in adult murine bone marrow. Prevalence of CD3+CD4-CD8- and alpha beta TCR+NK1.1+ cells.
复制标题
成年小鼠骨髓中异常的 T 细胞群。
作者：
M. Sykes
在正常小鼠骨髓中存在的T细胞群以前没有被详细分析，主要是因为它们相对稀少。为了进行此类分析，通过耗尽Mac 1阳性细胞（占骨髓细胞（BMC）的65%至90%）来富集骨髓T细胞，然后通过双色流式细胞术进行研究。对剩余细胞的分析表明，成年小鼠骨髓的T细胞谱与其他淋巴器官的T细胞谱明显不同。非常高比例的骨髓CD 3+细胞（约三分之一）是CD 4-CD 8-。CD 3 + CD 4-CD 8-细胞在BMC T细胞中比在胸腺细胞或脾T细胞中更集中，这表明骨髓可能是胸腺外TCR基因重排的位点，或者是这些细胞从胸腺回家的主要位点。还在Mac 1耗尽的BMC群体上评估NK1.1的表达。令人惊讶的是，发现高达39%的α β TCR+ BMC表达NK1.1。大多数α β TCR+NK1.1+ BMC也表达CD 4或CD 8。NK1.1+ α β TCR+细胞在BMC T细胞中所占的比例远高于其他淋巴（脾细胞或胸腺细胞）T细胞群。Mac 1耗尽的裸小鼠BMC含有非常少的具有这种表型的细胞。这些结果与NK1.1+ α β TCR+细胞主要在正常动物的胸腺中产生并优先迁移至骨髓的假设一致，在骨髓中它们可能作为造血的调节元件发挥作用。
The T cell populations present in normal murine bone marrow have not been previously analyzed in detail, mainly because of their relative rarity. In order to permit such analyses, bone marrow T cells were enriched by depleting Mac1-positive cells, which constitute 65 to 90% of bone marrow cells (BMC), and then studied by two-color flow cytometry. Analysis of the remaining cells revealed that the T cell profile of adult murine bone marrow is markedly different from that of other lymphoid organs. A very high proportion of bone marrow CD3+ cells (approximately one-third) are CD4-CD8-. CD3+CD4-CD8- cells are much more concentrated among BMC T cells than among thymocytes or splenic T cells, suggesting that bone marrow may be either a site of extrathymic TCR gene rearrangement, or a major site to which such cells home from the thymus. The expression of NK1.1 was also evaluated on Mac1-depleted BMC populations. Surprisingly, up to 39% of alpha beta TCR+ BMC were found to express NK1.1. Most alpha beta TCR+NK1.1+ BMC also expressed CD4 or CD8. NK1.1+ alpha beta TCR+ cells represented a much greater proportion of BMC T cells than of other lymphoid (splenocyte or thymocyte) T cell populations. Mac1-depleted BMC of nude mice contained very few cells with this phenotype. These results are consistent with the hypothesis that NK1.1+ alpha beta TCR+ cells are generated primarily in the thymus of normal animals and migrate preferentially to bone marrow, where they may function as regulatory elements in hematopoiesis.