Bandi Sriram, Akkina Ramesh
Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523, USA.
AIDS Res Ther. 2008 Jan 23;5:1. doi: 10.1186/1742-6405-5-1.
Human embryonic stem (hES) cells hold considerable promise for cell replacement and gene therapies. Their remarkable properties of pluripotency, self-renewal, and tractability for genetic modification potentially allows for the production of sizeable quantities of therapeutic cells of the hematopoietic lineage. Dendritic cells (DC) arise from CD34+ hematopoietic progenitor cells (HPCs) and are important in many innate and adaptive immune functions. With respect to HIV-1 infection, DCs play an important role in the efficient capture and transfer of the virus to susceptible cells. With an aim of generating DCs from a renewable source for HIV-1 studies, here we evaluated the capacity of hES cell derived CD34+ cells to give rise to DCs which can support HIV-1 infection.
Undifferentiated hES cells were cultured on S17 mouse bone marrow stromal cell layers to derive CD34+ HPCs which were subsequently grown in specific cytokine differentiation media to promote the development of DCs. The hES derived DCs (hES-DC) were subjected to phenotypic and functional analyses and compared with DCs derived from fetal liver CD34+ HPC (FL-DC). The mature hES-DCs displayed typical DC morphology consisting of veiled stellate cells. The hES-DCs also displayed characteristic phenotypic surface markers CD1a, HLA-DR, B7.1, B7.2, and DC-SIGN. The hES-DCs were found to be capable of antigen uptake and stimulating naïve allogeneic CD4+ T cells in a mixed leukocyte reaction assay. Furthermore, the hES-DCs supported productive HIV-1 viral infection akin to standard DCs.
Phenotypically normal and functionally competent DCs that support HIV-1 infection can be derived from hES cells. hES-DCs can now be exploited in applied immunology and HIV-1 infection studies. Using gene therapy approaches, it is now possible to generate HIV-1 resistant DCs from anti-HIV gene transduced hES-CD34+ hematopoietic progenitor cells.
人类胚胎干细胞(hES细胞)在细胞替代和基因治疗方面具有巨大潜力。它们具有多能性、自我更新以及易于进行基因修饰等显著特性,这有可能用于大量生产造血谱系的治疗性细胞。树突状细胞(DC)起源于CD34+造血祖细胞(HPC),在许多先天性和适应性免疫功能中发挥重要作用。就HIV-1感染而言,DC在病毒有效捕获并转移至易感细胞过程中起重要作用。为了从可再生来源生成用于HIV-1研究的DC,我们在此评估了hES细胞来源的CD34+细胞产生能够支持HIV-1感染的DC的能力。
将未分化的hES细胞培养于S17小鼠骨髓基质细胞层上,以获得CD34+HPC,随后在特定细胞因子分化培养基中培养以促进DC的发育。对hES来源的DC(hES-DC)进行表型和功能分析,并与源自胎儿肝脏CD34+HPC的DC(FL-DC)进行比较。成熟的hES-DC呈现出典型的DC形态,由带面纱的星状细胞组成。hES-DC还表现出特征性的表型表面标志物CD1a、HLA-DR、B7.1、B7.2和DC-SIGN。在混合淋巴细胞反应试验中,发现hES-DC能够摄取抗原并刺激未致敏的同种异体CD4+T细胞。此外,hES-DC支持与标准DC类似的HIV-1病毒的有效感染。
能够支持HIV-1感染的表型正常且功能健全的DC可从hES细胞中获得。hES-DC现在可用于应用免疫学和HIV-1感染研究。利用基因治疗方法,现在有可能从抗HIV基因转导的hES-CD34+造血祖细胞中产生抗HIV-1的DC。