Corbeau P, Haran M, Binz H, Devaux C
CRBM-UPR 9008 du CNRS, Institut de Biologie-Faculté de Médecine, Montpellier, France.
Mol Immunol. 1994 Jun;31(8):569-75. doi: 10.1016/0161-5890(94)90164-3.
Jacalin is a multimeric plant lectin able to interact with the lymphocyte cell-surface molecule CD4, a known receptor for the human immunodeficiency virus type 1 (HIV-1). Moreover, jacalin is able to block HIV-1 infection of CD4+ lymphoblastoid cells. Here we studied whether jacalin prevents HIV-1 gp120-CD4 interactions. We found (i) that jacalin did not inhibit HIV-1 Lai-induced syncytium formation that requires gp120-CD4 interactions; (ii) that jacalin prevented neither rgp120 binding to cell-surface CD4 nor sCD4 binding to viral envelope proteins expressed at the surface of HIV-1-infected lymphoblastoid cells; (iii) that jacalin did not compete for binding to CD4 with anti-CD4 mAb specific for the CDR2- or CDR3-like regions of the D1 domain of CD4; (iv) that jacalin did not bind a recombinant soluble molecule containing the D1/D2 domains of CD4; and, (iv) that jacalin binding to CD4 is inhibited by sugars known to interact with the lectinic-site of jacalin. These data have implications for the understanding of the mechanism by which jacalin blocks HIV-1 infection of CD4+ cells.
jacalin是一种多聚体植物凝集素，能够与人免疫缺陷病毒1型（HIV-1）的已知受体——淋巴细胞细胞表面分子CD4相互作用。此外，jacalin能够阻断HIV-1对CD4+淋巴母细胞的感染。在此，我们研究了jacalin是否能阻止HIV-1 gp120与CD4的相互作用。我们发现：（i）jacalin不抑制需要gp120-CD4相互作用的HIV-1 Lai诱导的合胞体形成；（ii）jacalin既不能阻止rgp120与细胞表面CD4的结合，也不能阻止sCD4与HIV-1感染的淋巴母细胞表面表达的病毒包膜蛋白的结合；（iii）jacalin不能与针对CD4 D1结构域中CDR2或CDR3样区域的抗CD4单克隆抗体竞争与CD4的结合；（iv）jacalin不与包含CD4 D1/D2结构域的重组可溶性分子结合；以及（v）已知与jacalin凝集素位点相互作用的糖类可抑制jacalin与CD4的结合。这些数据对于理解jacalin阻断HIV-1感染CD4+细胞的机制具有重要意义。
