Humblet C, Defresne M P, Greimers R, Rongy A M, Boniver J
Department of Pathology, University Hospital, Liege, Belgium.
Leukemia. 1989 Nov;3(11):813-8.
Whole body fractionated irradiation induces thymic lymphomas in C57BL/Ka mice after a latent period during which intrathymic lymphopoiesis is modified; thymocyte numbers are subnormal and the epithelial component of thymic nurse cells (TNCs) is altered as estimated by the number of TNCs in vivo and by its ability to interact with immature thymocytes in vitro. A graft of normal bone marrow cells immediately after the last irradiation prevents the development of lymphomas; but when such a graft is performed 1 month later, it does not inhibit the emergence of tumors. In both cases the grafted precursors home and repopulate the thymus. However, the delayed graft does not exert any effect upon the altered epithelial component of TNCs, whereas the early one restores the numbers of TNCs and the function of their epithelial component. The results thus demonstrate that lymphoid thymic repopulation by a bone marrow graft is not sufficient to prevent the development of lymphomas and that there is an intimate relationship between tumor development and alterations of nurse cells microenvironment.
全身分次照射在一段潜伏期后可诱导C57BL/Ka小鼠发生胸腺淋巴瘤，在此潜伏期内胸腺内淋巴细胞生成发生改变；胸腺细胞数量低于正常水平，胸腺哺育细胞（TNCs）的上皮成分也发生改变，这可通过体内TNCs的数量及其在体外与未成熟胸腺细胞相互作用的能力来估计。在最后一次照射后立即移植正常骨髓细胞可预防淋巴瘤的发生；但如果在1个月后进行这种移植，则不能抑制肿瘤的出现。在这两种情况下，移植的前体细胞都会归巢并重新填充胸腺。然而，延迟移植对TNCs改变的上皮成分没有任何影响，而早期移植则可恢复TNCs的数量及其上皮成分的功能。因此，结果表明骨髓移植对胸腺的淋巴细胞再填充不足以预防淋巴瘤的发生，并且肿瘤发生与哺育细胞微环境的改变之间存在密切关系。
