Encapsulation of foreign targets by hemocytes of the moth Pseudoplusia includens (Lepidoptera: Noctuidae) involves an RGD-dependent cell adhesion mechanism
Encapsulation of foreign targets by hemocytes of the moth Pseudoplusia includens (Lepidoptera: Noctuidae) involves an RGD-dependent cell adhesion mechanism
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DOI：
10.1016/0022-1910(94)00136-5
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发表时间：
1995-06
影响因子：
2.2
通讯作者：
L. L. Pech-L.;M. Strand
中科院分区：
文献类型：
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作者：
L. L. Pech-L.;M. Strand
我们通过检测四肽RGDS对血细胞扩散和包封的影响，验证了昆虫免疫反应包封涉及RGDS依赖性细胞粘附机制的假设。浓度为0.5-2 mM的可溶性RGDS可抑制原代包封血细胞（浆细胞）在塑料组织培养板表面的扩散。在5 ~ 10 mM的浓度下，颗粒细胞的扩散也受到抑制。RGES不抑制浆细胞或颗粒细胞的扩散，表明其作用是RGDS特异性的。RGDS-Sepharose珠被血细胞包裹，而RGES-Sepharose珠不被血细胞包裹。此外，可溶性RGDS对RGDS- sepharose的体外包封有抑制作用，而RGES没有。RGDS-Sepharose在3 h内被包裹，而RGES-Sepharose在24 h后才被包裹。唯一被包裹RGDS-Sepharose的血细胞形态是浆细胞。最后,祝好。而RGES对无细胞血浆有抑制浆细胞扩散的作用。这些结果表明，细胞粘附介导昆虫血细胞扩散和包封的分子基础涉及含有RGD识别序列的细胞粘附分子。
We tested the hypothesis that an insect immune response, encapsulation, involves an RGD-dependent cell adhesion mechanism by examining the effects of the tetrapeptide RGDS on hemocyte spreading and encapsulation. Soluble RGDS at concentrations of 0.5–2 mM inhibited the spreading of the primary encapsulating hemocyte, the plasmatocyte, on the surface of plastic tissue culture plates. At concentrations of 5–10 mM, the spreading of granular cells was also inhibited. RGES did not inhibit plasmatocyte or granular cell spreading, indicating that the effect was specific for RGDS. RGDS-Sepharose beads were encapsulated by hemocytes in vitro, whereas RGES-Sepharose beads were not. Furthermore, soluble RGDS, but not RGES, inhibited in vitro encapsulation of RGDS-Sepharose. When injected into the hemocoel of P. includens larvae, RGDS-Sepharose was encapsulated in 3 h, whereas RGES-Sepharose was not encapsulated until 24 h. The only hemocyte morphotype to encapsulate RGDS-Sepharose was the plasmatocyte. Lastly, RGDS. but not RGES, inhibited plasmatocyte spreading in response to cell-free plasma. These results indicate that the molecular basis of cell adhesion mediating hemocyte spreading and encapsulation in insects involves cell adhesion molecules containing the RGD recognition sequence.