Isaac J, Kerby J D, Russell W J, Dempsey S C, Sanders P W, Herrera G A
Department of Pathology, Louisiana State University Medical Center, Shreveport, LA 71130, USA.
Amyloid. 1998 Dec;5(4):238-46. doi: 10.3109/13506129809007296.
We have shown in vitro AL-amyloid formation by human mesangial cells (HMCs). AL-amyloid formation may require lysosomal processing of the light chains (LCs) by HMCs for amyloidogenesis to occur. Chloroquine inhibits lysosomal activity. TGF-beta mediates extracellular matrix formation in many glomerulopathies. Thrombospondin (TSP) has been proposed as a mediator of cell proliferation and a marker of early fibrosis. We investigated amyloid formation by HMCs exposed to AL-LCs in the absence of amyloid enhancing factor (AEF). The effects of TGF-beta, TSP and chloroquine on in vitro amyloid formation were studied. HMCs were incubated with two AL-LCs, a light chain deposition disease (LCDD)-LC, or one of two tubulopathic LCs (T-LCs). Additional cells were treated with an AL-LC and chloroquine, TGF-beta, or TSP. Amyloid formation was evaluated microscopically using hematoxylin and eosin, Congo red and Thioflavin-T stains, as well as ultrastructurally. Amyloid was formed only when HMCs were incubated with AL-LCs. Addition of TSP significantly enhanced amyloid formation. In contrast, exogenous TGF-beta and chloroquine significantly attenuated amyloid formation. These findings show that some AL-LCs do not require AEF for amyloidogenesis to occur, and that chloroquine, TGF-beta and sTSP modulate in vitro AL-amyloidosis.
我们已经证明人系膜细胞（HMCs）可在体外形成淀粉样轻链（AL-淀粉样蛋白）。AL-淀粉样蛋白的形成可能需要HMCs对轻链（LCs）进行溶酶体处理才能发生淀粉样变。氯喹可抑制溶酶体活性。转化生长因子-β（TGF-β）在许多肾小球疾病中介导细胞外基质形成。血小板反应蛋白（TSP）已被认为是细胞增殖的介质和早期纤维化的标志物。我们研究了在没有淀粉样增强因子（AEF）的情况下，暴露于AL-LCs的HMCs的淀粉样蛋白形成情况。研究了TGF-β、TSP和氯喹对体外淀粉样蛋白形成的影响。将HMCs与两种AL-LCs、一种轻链沉积病（LCDD）-LC或两种肾小管病LCs（T-LCs）之一一起孵育。另外的细胞用一种AL-LC和氯喹、TGF-β或TSP处理。使用苏木精和伊红、刚果红和硫黄素-T染色在显微镜下评估淀粉样蛋白的形成，并进行超微结构评估。只有当HMCs与AL-LCs一起孵育时才会形成淀粉样蛋白。添加TSP可显著增强淀粉样蛋白的形成。相比之下，外源性TGF-β和氯喹可显著减弱淀粉样蛋白的形成。这些发现表明，一些AL-LCs在淀粉样变发生时不需要AEF，并且氯喹、TGF-β和sTSP可调节体外AL-淀粉样变性。
