Herman I M, D'Amore P A
J Cell Biol. 1985 Jul;101(1):43-52. doi: 10.1083/jcb.101.1.43.
We have affinity-fractionated rabbit antiactin immunoglobulins (IgG) into classes that bind preferentially to either muscle or nonmuscle actins. The pools of muscle- and nonmuscle-specific actin antibodies were used in conjunction with fluorescence microscopy to characterize the actin in vascular pericytes, endothelial cells (EC), and smooth muscle cells (SMC) in vitro and in situ. Nonmuscle-specific antiactin IgG stained the stress fibers of cultured EC and pericytes but did not stain the stress fibers of cultured SMC, although the cortical cytoplasm associated with the plasma membrane of SMC did react with nonmuscle-specific antiactin. Whereas the muscle-specific antiactin IgG failed to stain EC stress fibers and only faintly stained their cortical cytoplasm, these antibodies reacted strongly with the fiber bundles of cultured SMC and pericytes. Similar results were obtained in situ. The muscle-specific antiactin reacted strongly with the vascular SMC of arteries and arterioles as well as with the perivascular cells (pericytes) associated with capillaries and post-capillary venules. The non-muscle-specific antiactin stained the endothelium and the pericytes but did not react with SMC. These findings indicate that pericytes in culture and in situ possess both muscle and nonmuscle isoactins and support the hypothesis that the pericyte may represent the capillary and venular correlate of the SMC.
我们已将兔抗肌动蛋白免疫球蛋白（IgG）通过亲和分级分离为优先结合肌肉肌动蛋白或非肌肉肌动蛋白的类别。肌肉特异性和非肌肉特异性肌动蛋白抗体库与荧光显微镜结合使用，以在体外和原位表征血管周细胞、内皮细胞（EC）和平滑肌细胞（SMC）中的肌动蛋白。非肌肉特异性抗肌动蛋白IgG可使培养的EC和周细胞的应力纤维染色，但不能使培养的SMC的应力纤维染色，尽管与SMC质膜相关的皮质细胞质确实与非肌肉特异性抗肌动蛋白发生反应。而肌肉特异性抗肌动蛋白IgG未能使EC应力纤维染色，仅使其皮质细胞质微弱染色，这些抗体与培养的SMC和周细胞的纤维束强烈反应。在原位也获得了类似结果。肌肉特异性抗肌动蛋白与动脉和小动脉的血管SMC以及与毛细血管和毛细血管后微静脉相关的血管周围细胞（周细胞）强烈反应。非肌肉特异性抗肌动蛋白使内皮和周细胞染色，但不与SMC反应。这些发现表明，培养的和原位的周细胞同时具有肌肉和非肌肉同工肌动蛋白，并支持周细胞可能代表SMC的毛细血管和微静脉对应物的假说。
