Guendel Irene, Iordanskiy Sergey, Sampey Gavin C, Van Duyne Rachel, Calvert Valerie, Petricoin Emanuel, Saifuddin Mohammed, Kehn-Hall Kylene, Kashanchi Fatah
Department of Systems Biology, National Center for Biodefense and Infectious Diseases, George Mason University, Manassas, VA, 20110, USA.
J Neurovirol. 2015 Jun;21(3):257-75. doi: 10.1007/s13365-015-0323-5. Epub 2015 Feb 12.
Many cellular cofactors have been documented to be critical for various stages of viral replication. Using high-throughput proteomic assays, we have previously identified Bruton's tyrosine kinase (BTK) as a host protein that was uniquely upregulated in the plasma membrane of human immunodeficiency virus (HIV-1)-infected T cells. Here, we have further characterized the BTK expression in HIV-1 infection and show that this cellular factor is specifically expressed in infected myeloid cells. Significant upregulation of the phosphorylated form of BTK was observed in infected cells. Using size exclusion chromatography, we found BTK to be virtually absent in the uninfected U937 cells; however, new BTK protein complexes were identified and distributed in both high molecular weight (∼600 kDa) and a small molecular weight complex (∼60-120 kDa) in the infected U1 cells. BTK levels were highest in cells either chronically expressing virus or induced/infected myeloid cells and that BTK translocated to the membrane following induction of the infected cells. BTK knockdown in HIV-1-infected cells using small interfering RNA (siRNA) resulted in selective death of infected, but not uninfected, cells. Using BTK-specific antibody and small-molecule inhibitors including LFM-A13 and a FDA-approved compound, ibrutinib (PCI-32765), we have found that HIV-1-infected cells are sensitive to apoptotic cell death and result in a decrease in virus production. Overall, our data suggests that HIV-1-infected cells are sensitive to treatments targeting BTK expressed in infected cells.
许多细胞辅助因子已被证明对病毒复制的各个阶段至关重要。通过高通量蛋白质组学分析，我们之前已鉴定出布鲁顿酪氨酸激酶（BTK）是一种宿主蛋白，在人类免疫缺陷病毒（HIV-1）感染的T细胞膜中独特地上调。在此，我们进一步表征了HIV-1感染中BTK的表达，并表明这种细胞因子在受感染的髓样细胞中特异性表达。在受感染细胞中观察到BTK磷酸化形式的显著上调。使用尺寸排阻色谱法，我们发现未感染的U937细胞中几乎不存在BTK；然而，在受感染的U1细胞中鉴定出了新的BTK蛋白复合物，并分布在高分子量（约600 kDa）和小分子量复合物（约60-120 kDa）中。BTK水平在长期表达病毒的细胞或诱导/感染的髓样细胞中最高，并且在感染细胞诱导后BTK会转移到膜上。使用小干扰RNA（siRNA）敲低HIV-1感染细胞中的BTK会导致受感染而非未感染细胞的选择性死亡。使用BTK特异性抗体和包括LFM-A13和一种FDA批准的化合物依鲁替尼（PCI-32765）在内的小分子抑制剂，我们发现HIV-1感染的细胞对凋亡性细胞死亡敏感，并导致病毒产生减少。总体而言，我们的数据表明，HIV-1感染的细胞对针对受感染细胞中表达的BTK的治疗敏感。
