IDENTIFICATION OF HIV PROTEINS THAT STIMULATE MONOKINE SECRETION

刺激单核因子分泌的 HIV 蛋白的鉴定

• 批准号: 3804744
• 负责人: K CLOUSE-STREBEL
• 金额: --
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3804744
• 关键词: CD4 molecule; HIV envelope protein gp120; HIV infections; biological signal transduction; cellular immunity; chimeric proteins; colony stimulating factor; gene expression; genetic manipulation; human immunodeficiency virus; human tissue; immunoregulation; interleukin 1; interleukin 6; macrophage; monokines; secretion; tumor necrosis factor alpha; virus antigen; virus envelope; virus protein; virus receptors; virus replication

We have previously demonstrated that select viral antigens, including human immunodeficiency virus (HIV) itself, can stimulate human macrophages (MO) to secrete monokines capable of upregulating HIV expression in chronically infected human cells. Subsequent investigations to determine which HIV proteins were capable of stimulating monokine production revealed that the natural gp120 envelope protein could mediate this response, whereas the natural capsid protein could not. We found that natural gp120 stimulates MO to release TNF-alpha, IL-1beta, IL-6 and GM- CSF, and this effect could be blocked with soluble CD4. Analysis utilizing recombinant HIV proteins demonstrate that envelope proteins expressed in baculovirus, including gp160 and gp120, are unable to stimulate monokine secretion. Similarly, a recombinant gp120 fusion protein expressed in Chinese hamster ovary (CHO) cells is unable to function in this capacity. However, a full-length recombinant gp120 expressed in CHO cells is capable of stimulating monokine production. The stimulatory capacity of both natural and full-length CHO-cell derived gp120 was eliminated by heating at 100 degrees C, and could be blocked with excess CHO-cell derived recombinant gp120 fusion protein. Since the baculovirus-expressed gp120 and the CHO-cell derived recombinant fusion protein bind to CD4, these test results suggest that HIV gp120 binding to CD4 on the MO surface may of itself be insufficient for stimulation of monokine secretion.

我们之前已经证明了选定的病毒抗原，包括 人类免疫缺陷病毒(HIV)本身，可以刺激人类巨噬细胞 (Mo)分泌能够上调HIV表达的单因子 慢性感染的人类细胞。后续调查以确定 哪些HIV蛋白能够刺激单核细胞产生 揭示了天然的gp120包膜蛋白可以介导这一过程。 而天然衣壳蛋白则不能。我们发现 天然gp120刺激巨噬细胞释放TNF-α、IL-1β、IL-6和GM-1 这一作用可被可溶性CD_4阻断。分析 利用重组HIV蛋白证明包膜蛋白 在杆状病毒中表达的，包括gp160和gp120，无法 刺激单核细胞分泌。同样，重组gp120融合 在中国仓鼠卵巢(CHO)细胞中表达的蛋白质无法 以这种身份发挥作用。然而，全长重组gp120 在CHO细胞中表达能够刺激单核因子的产生。这个 天然和全长CHO细胞的刺激能力 Gp120在100摄氏度加热后被消除，并可被阻断 与过量的CHO细胞来源的重组gp120融合蛋白。自.以来 杆状病毒表达的gp120与CHO细胞来源的重组融合 这些试验结果表明，HIV gp120结合到 MO表面上的CD_4本身可能不足以刺激 单核细胞分泌。