Pruenster Monika, Wilflingseder Doris, Bánki Zoltán, Ammann Christoph G, Muellauer Brigitte, Meyer Martina, Speth Cornelia, Dierich Manfred P, Stoiber Heribert
Division of Hygiene and Microbiology, Innsbruck Medical University, Ludwig Boltzmann Institute for AIDS Research, Innsbruck, Austria.
Eur J Immunol. 2005 Sep;35(9):2691-8. doi: 10.1002/eji.200425940.
HIV directly activates the complement cascade and is, therefore, opsonized with C3-cleavage products in vivo. This cloud of C3 fragments on the viral surface may impair the interaction of the HIV envelope glycoproteins gp120/gp41 with C-type lectins expressed on immature dendritic cells (iDC). Therefore, we determined the accessibility of gp120 after opsonization and compared the interaction of DC with non-opsonized or complement-opsonized HIV. The recognition of native gp120 was drastically impaired when the virus was covered by complement. Independent of opsonization, similar amounts of HIV bound to DC. The interaction of iDC and the infection of DC-PBL co-cultures with non-opsonized virus was significantly reduced by mannan and antibodies which inhibit the ICAM-1-CR3 interaction. The binding of opsonized virus to iDC was reduced by an anti-CR3-antibody, which interferes with the binding of C3 fragments, but was not affected by mannan. Complement enhanced the HIV infection of DC and DC-PBL co-cultures significantly. Mannan did not inhibit the complement-dependent enhancement of infection. Thus, non-opsonized and opsonized HIV interacted with iDC, although the binding mechanisms seemed to differ. As HIV is opsonized in vivo, the C-type lectin-independent interaction of opsonized viruses with iDC has to be taken into account.
HIV可直接激活补体级联反应，因此在体内会被C3裂解产物调理。病毒表面的这层C3片段可能会损害HIV包膜糖蛋白gp120/gp41与未成熟树突状细胞（iDC）上表达的C型凝集素之间的相互作用。因此，我们测定了调理后gp120的可及性，并比较了树突状细胞与未调理或补体调理的HIV之间的相互作用。当病毒被补体覆盖时，对天然gp120的识别会受到严重损害。无论是否进行调理，与树突状细胞结合的HIV量相似。甘露聚糖和抑制ICAM-1-CR3相互作用的抗体可显著降低iDC与未调理病毒之间的相互作用以及DC-PBL共培养物被未调理病毒感染的几率。抗CR3抗体可减少调理病毒与iDC的结合，该抗体可干扰C3片段的结合，但不受甘露聚糖影响。补体可显著增强树突状细胞和DC-PBL共培养物的HIV感染。甘露聚糖不会抑制补体依赖性感染增强作用。因此，未调理和调理的HIV均可与iDC相互作用，尽管其结合机制似乎有所不同。由于HIV在体内会被调理，因此必须考虑调理病毒与iDC之间不依赖C型凝集素的相互作用。
