Mezzano S, Burgos M E, Ardiles L, Olavarria F, Concha M, Caorsi I, Aranda E, Mezzano D
Department of Pathology, School of Medicine, Universidad Austral, Valdivia, Chile.
Nephron. 1992;61(1):58-63. doi: 10.1159/000186835.
Since platelet factor 4 (PF4), a cationic (pI 7.6) platelet secretory protein, binds avidly to glomerular polyanions both in vitro and in vivo, and is implicated in neutrophil chemotaxis, we studied by indirect immunofluorescence microscopy the presence of PF4 deposits in glomeruli of patients with poststreptococcal nephritis (APSGN). Goat antihuman PF4 serum was used as primary antibody and fluorescein-conjugated IgG fraction of rabbit antigoat IgG as second antibody. Controls consisted of nonimmune goat serum or anti-PF4 serum preabsorbed with human PF4, as primary antibodies. Glomerular deposits of PF4 were demonstrated in renal tissues obtained by biopsy in 14 of 20 patients studied; the deposits were particularly intense in 9 patients. PF4 was bound to the mesangium and to the capillary walls. There was a significant positive correlation between intraglomerular deposits of PF4 and the levels of proteinuria (p = 0.024). These findings provide further evidence for a role of platelets in the pathogenesis of APSGN and suggest that PF4 may contribute to alter the glomerular permeability in this disease.
由于血小板因子4（PF4）是一种阳离子性（等电点7.6）的血小板分泌蛋白，在体外和体内均能与肾小球多阴离子紧密结合，且与中性粒细胞趋化性有关，我们通过间接免疫荧光显微镜研究了链球菌感染后肾小球肾炎（APSGN）患者肾小球中PF4沉积物的存在情况。以山羊抗人PF4血清作为一抗，兔抗山羊IgG的荧光素结合IgG片段作为二抗。对照包括非免疫山羊血清或用人PF4预先吸附的抗PF4血清作为一抗。在所研究的20例患者中，有14例经活检获得的肾组织中证实存在PF4的肾小球沉积物；其中9例患者的沉积物尤为明显。PF4与系膜和毛细血管壁结合。PF4的肾小球内沉积物与蛋白尿水平之间存在显著正相关（p = 0.024）。这些发现为血小板在APSGN发病机制中的作用提供了进一步证据，并提示PF4可能在该疾病中导致肾小球通透性改变。
