Troianovskiĭ S M
Tsitologiia. 1987 Jun;29(6):727-31.
Prekeratin of simple epithelia with m.m. 55 kD (PK55) was found in all the studied tumorigenic and non-tumorigenic liver epithelial cell lines of the IAR series by means of indirect immunofluorescent methods in combination with corresponding monoclonal antibodies. The most prominent expression was observed in some tumorigenic cell lines. Expression of PK55 was reversible--the cells lost prekeratin in low density cultures. It has been found that the synthesis of prekeratins with m.m. 49 kD (PK49) and 40 kD (PK40) began on reaching higher cell densities than those needed for PK55 synthesis in IAR6-7 line. The PK40 appeared in cells spread on the substratum, while the PK49 was observed in upper poorly spread cells of ridges in multilayered dense cultures. Thus, the synthesis of prekeratins is not constitutive at least for some types of epithelial cells. Specific cell-to-cell interactions are presumably needed for each particular prekeratin synthesis induction.
通过间接免疫荧光法结合相应单克隆抗体，在IAR系列所有研究的致瘤性和非致瘤性肝上皮细胞系中发现了分子量为55kD的简单上皮前角蛋白（PK55）。在一些致瘤性细胞系中观察到最显著的表达。PK55的表达是可逆的——细胞在低密度培养中失去前角蛋白。已经发现，在IAR6 - 7细胞系中，分子量为49kD（PK49）和40kD（PK40）的前角蛋白的合成开始于比PK55合成所需更高的细胞密度。PK40出现在铺展在基质上的细胞中，而PK49在多层致密培养物中嵴上铺展不良的上层细胞中观察到。因此，至少对于某些类型的上皮细胞，前角蛋白的合成不是组成性的。推测每种特定前角蛋白合成的诱导需要特定的细胞间相互作用。
