French L E, Tschopp J, Schifferli J A
Department of Medicine, Hôpital Cantonal Universitaire, Geneva, Switzerland.
Clin Exp Immunol. 1992 Jun;88(3):389-93. doi: 10.1111/j.1365-2249.1992.tb06459.x.
The membrane attack complex (MAC) of complement is activated by immune and non-immune mechanisms in the kidney. MAC has been found associated with glomerular immune deposits, but also to cell remnants, particularly along tubules and in vessel walls. Clusterin and S-protein (vitronectin) bind to MAC, rendering it cytolytically inactive. Both have been found associated with MAC in renal tissue. Here we analysed the deposition of clusterin and S-protein in 118 renal biopsies relative to the localization of the MAC using MoAbs. Statistical analysis was performed comparing no or little versus evident or strong staining by immunofluorescence (IF). In glomeruli, out of the 92 biopsies where both MAC and immunoglobulins were evaluated, deposits of MAC were found in the presence (32 out of 41) but also in the absence of immunoglobulins (20/51). Clusterin and S-protein deposits were seen, respectively, in 25 out of 61 and 36 out of 61 biopsies containing glomerular MAC, and almost never in its absence (one out of 50 for both). The association of the two inhibitors with MAC was observed mainly in glomeruli containing immunoglobulin deposits (respectively, 21 out of 32 and 25 out of 32), but not when immunoglobulins were absent (three out of 20 and seven out of 20) (coefficient of concordance, K = 0.47 and 0.43). The localization of MAC along tubules and in vessels was easily identified in most biopsies (93 out of 118) and was accompanied by S-protein in most cases (tubules, 86 out of 93; vessels, 82 out of 93) (K = 0.58 and 0.57 respectively) but not by clusterin (28 out of 93 and 24 out of 93). These results suggest that clusterin does not co-localize with MAC whenever there is formation and fixation of the MAC. It seems that clusterin has a particular affinity for MAC which is associated with immunoglobulin. This observation should help to distinguish between the different forms of MAC, and might indicate that MAC associated with immunoglobulin is essentially in its cytolytically inactive form.
补体膜攻击复合物（MAC）在肾脏中可通过免疫和非免疫机制被激活。已发现MAC与肾小球免疫沉积物相关，但也与细胞残余物相关，特别是沿肾小管和血管壁处。簇集素和S蛋白（玻连蛋白）与MAC结合，使其失去细胞溶解活性。在肾组织中均已发现它们与MAC相关。在此，我们使用单克隆抗体（MoAbs）分析了118例肾活检组织中簇集素和S蛋白的沉积情况，并与MAC的定位进行了对比。通过免疫荧光（IF）对无或少量染色与明显或强染色进行比较，进行了统计学分析。在肾小球中，在评估了MAC和免疫球蛋白的92例活检组织中，MAC沉积物在有免疫球蛋白存在时（41例中有32例）以及无免疫球蛋白时（51例中有20例）均被发现。在含有肾小球MAC的61例活检组织中，分别有25例和36例可见簇集素和S蛋白沉积物，而在无MAC时几乎未见（两者均为50例中有1例）。两种抑制剂与MAC的关联主要在含有免疫球蛋白沉积物的肾小球中观察到（分别为32例中有21例和32例中有25例），而在无免疫球蛋白时则未观察到（20例中有3例和20例中有7例）（一致性系数，K = 0.47和0.43）。在大多数活检组织（118例中有93例）中，很容易识别出沿肾小管和血管的MAC定位，并且在大多数情况下伴有S蛋白（肾小管，93例中有86例；血管，93例中有82例）（K分别为0.58和0.57），但簇集素则不然（93例中有28例和93例中有24例）。这些结果表明，每当MAC形成并固定时，簇集素并不与MAC共定位。似乎簇集素对与免疫球蛋白相关的MAC具有特殊亲和力。这一观察结果应有助于区分MAC的不同形式，并且可能表明与免疫球蛋白相关的MAC基本上处于其细胞溶解无活性形式。
