Niblack G D, Kateley J R, Gengozian N
Immunology. 1977 Feb;32(2):257-63.
Marmosets are natural blood chimeras, this condition resulting from the high frequency of fraternal twinning and the consistent development of placental vasular anastomoses between the two embryos. Identification of chimerism by sex-chromosome analysis of cultured blood lymphocytes provided a means of determining the proportion of chimerism among T and B lymphocytes. Peripheral blood lymphocytes were enriched for T or B cells by filtration through a nylon column (yields greater than 95 per cent T-cells) or inactivation of T lymphocytes by treatment with a goat anti-marmoset thymocyte antiserum in the presence of complement (yeilds greater than 95 per cent B cells). Mitogenic stimulation of these separated, enriched cell populations yielded metaphase plates which could be scored for percentage male and female cells. Tests on five different blood chimeras showed the T- and B-lymphocyte chimerism to be the same. Stimulation of blood lymphocytes with cells from another species of marmoset in a mixed lymphocyte culture test revealed the chimeric T-cell response (i.e., host and co-twin cells) to be similar to that obtained with a mitogenic lectin. The demonstration of equivalent T- and B-cell chimerism in these animals suggests derivation of these cells from a common stem cell pool and the response of both T-cell populations to an antigenic stimulus in proportions similar to their percentage chimerism suggests complete immunologic tolerance exists in this species for co-twin histocompatibility antigens.
狨猴是天然的血液嵌合体，这种情况源于异卵双生的高发生率以及两个胚胎之间胎盘血管吻合的持续发展。通过对培养的血液淋巴细胞进行性染色体分析来鉴定嵌合体，为确定T淋巴细胞和B淋巴细胞中嵌合体的比例提供了一种方法。通过尼龙柱过滤（T细胞产率大于95%）或在补体存在下用山羊抗狨猴胸腺细胞抗血清处理使T淋巴细胞失活（B细胞产率大于95%），可使外周血淋巴细胞富集T细胞或B细胞。对这些分离、富集的细胞群体进行促有丝分裂刺激，可产生中期板，可对其中雄性和雌性细胞的百分比进行计数。对五只不同的血液嵌合体进行的测试表明，T淋巴细胞和B淋巴细胞的嵌合情况相同。在混合淋巴细胞培养试验中，用另一种狨猴的细胞刺激血液淋巴细胞，结果显示嵌合T细胞反应（即宿主细胞和同卵双胞胎细胞）与用促有丝分裂凝集素获得的反应相似。这些动物中T细胞和B细胞嵌合情况相同的证明表明，这些细胞来源于一个共同的干细胞库，并且两个T细胞群体对抗抗原刺激的反应比例与其嵌合百分比相似，这表明该物种对同卵双胞胎组织相容性抗原存在完全免疫耐受。
