Katayama M L, Federico M H, Brentani R R, Brentani M M
Departamento de Radiologia, Faculdade de Medicina Universidade de São Paulo, Brazil.
Cell Adhes Commun. 1998 Jul;5(5):409-24. doi: 10.3109/15419069809010785.
Eosinophils accumulate into the uterus of ovariectomized rats, after treatment with estradiol (E2). We have investigated whether this feature is related to interactions of eosinophils with uterine extracellular matrix proteins: laminin (LM) and fibronectin (FN). Eosinophils isolated from the peritoneal cavity of ovariectomized rats displayed estrogen receptors measured at both binding activity and mRNA levels. An increased number of laminin binding sites, calculated by Scatchard analysis using iodinated LM was determined in E2-treated eosinophils (70,100 +/- 28,000 sites/cell vs 21,000 +/- 5,000 sites/cell in controls). Eo binding to 125I-LM- was inhibited by the E8-LM fragment. Estradiol up-regulated the expression in eosinophils of alpha 6 and beta 2 integrin subunits evaluated by flow-cytometry as well as by alpha 6 mRNA expression. After E2 treatment, eosinophils showed higher adhesiveness to LM-coated dishes (10 +/- 2 vs 56 +/- 3%) which was inhibited by monoclonal antibodies against alpha 6, beta 1 and beta 2 integrins and by the steroid antagonist tamoxifen. These monoclonal antibodies also blocked the attachment of stimulated eosinophils to uterine cryostat sections obtained from spayed rats previously treated with estradiol. We did not detect any apparent influence of E2 on basal eosinophil adherence or binding to FN although alpha 4 and alpha 5 integrin subunits were expressed in eosinophils. Expression of laminin and merosin in the uterus was determined immunohistochemically. Our results suggest that integrin-laminin interactions may contribute to the preferential eosinophil recruitment in vivo.
在经雌二醇（E2）处理后，嗜酸性粒细胞会积聚到卵巢切除大鼠的子宫中。我们研究了这一特性是否与嗜酸性粒细胞与子宫细胞外基质蛋白：层粘连蛋白（LM）和纤连蛋白（FN）的相互作用有关。从卵巢切除大鼠的腹腔中分离出的嗜酸性粒细胞在结合活性和mRNA水平上均检测到雌激素受体。通过使用碘化LM的Scatchard分析计算得出，在E2处理的嗜酸性粒细胞中，层粘连蛋白结合位点数量增加（70,100±28,000个位点/细胞，而对照组为21,000±5,000个位点/细胞）。E8-LM片段可抑制嗜酸性粒细胞与125I-LM的结合。通过流式细胞术以及α6 mRNA表达评估，雌二醇上调了嗜酸性粒细胞中α6和β2整合素亚基的表达。E2处理后，嗜酸性粒细胞对LM包被的培养皿显示出更高的黏附性（10±2对56±3%），这被抗α6、β1和β2整合素的单克隆抗体以及类固醇拮抗剂他莫昔芬所抑制。这些单克隆抗体也阻断了受刺激的嗜酸性粒细胞与先前用雌二醇处理过的去势大鼠子宫冰冻切片的附着。尽管嗜酸性粒细胞中表达了α4和α5整合素亚基，但我们未检测到E2对嗜酸性粒细胞基础黏附或与FN结合有任何明显影响。通过免疫组织化学方法测定子宫中层粘连蛋白和merosin的表达。我们的结果表明，整合素-层粘连蛋白相互作用可能有助于体内嗜酸性粒细胞的优先募集。
