Holznagel E, Hofmann-Lehmann R, Allenspach K, Hüttner S, Willett B, Groscurth P, Niederer E, Lutz H
Department of Internal Veterinary Medicine, University of Zurich, Switzerland.
Vet Immunol Immunopathol. 1996 Jun 15;52(1-2):1-14. doi: 10.1016/0165-2427(95)05541-x.
Human peripheral blood lymphocytes (PBLs) from healthy individuals are resistant to in vitro-induced apoptosis, but activated human lymphocytes can readily undergo apoptosis. The activation of human lymphocytes is accompanied by the upregulation of a cell surface antigen, the major histocompatibility complex (MHC) class II-antigen. Only a minority of PBLs are usually MHC class II-antigen-positive in healthy humans. In contrast, in healthy cats the majority of feline PBLs are MHC class II-antigen-positive. We have, therefore, investigated the sensitivity of feline peripheral blood lymphocytes obtained from specified pathogen free (SPF) cats to the induction of apoptosis. Feline PBLs from SPF cats (n = 16) and human PBLs from healthy donors (n = 2) were isolated. After short-term culture, cells were examined for the presence of fragmented DNA as a result of apoptosis by a DNA agarose gel electrophoresis method and for the presence of DNA double strand breaks by in situ 3' end labeling. In addition, relative DNA content per cell was flow cytometrically determined using propidium iodide (PI) or 7-actinomycin-D (7-AAD) and apoptotic cells were identified on the basis of a reduced DNA content. Cell surface antigens and cellular DNA were analyzed simultaneously by dual-color flow cytometric analyses in order to study lymphocyte subsets. Single- and dual-color analysis revealed that, in contrast to human lymphocytes, feline lymphocytes rapidly underwent apoptosis when cultured overnight in medium. Furthermore, the majority of apoptotic cells was found within the MHC II-positive cell subject.
来自健康个体的人外周血淋巴细胞（PBLs）对体外诱导的凋亡具有抗性，但活化的人淋巴细胞可容易地发生凋亡。人淋巴细胞的活化伴随着细胞表面抗原——主要组织相容性复合体（MHC）II类抗原的上调。在健康人中，通常只有少数PBLs是MHC II类抗原阳性。相比之下，在健康猫中，大多数猫PBLs是MHC II类抗原阳性。因此，我们研究了从无特定病原体（SPF）猫获得的猫外周血淋巴细胞对凋亡诱导的敏感性。分离了来自SPF猫（n = 16）的猫PBLs和来自健康供体（n = 2）的人PBLs。短期培养后，通过DNA琼脂糖凝胶电泳法检测细胞中因凋亡而产生的DNA片段化情况，并通过原位3'端标记检测DNA双链断裂情况。此外，使用碘化丙啶（PI）或7-放线菌素-D（7-AAD）通过流式细胞术测定每个细胞的相对DNA含量，并根据DNA含量降低来鉴定凋亡细胞。为了研究淋巴细胞亚群，通过双色流式细胞术分析同时分析细胞表面抗原和细胞DNA。单色和双色分析显示，与人类淋巴细胞相反，猫淋巴细胞在培养基中过夜培养时迅速发生凋亡。此外，大多数凋亡细胞存在于MHC II阳性细胞群体中。
