- Poster presentation
- Open Access
Two independent functions of Vγ2Vδ2 T cells discriminated by CD16 during HIV-1 infection
© He et al; licensee BioMed Central Ltd. 2012
- Published: 13 September 2012
- Flow Cytometry
- Immune Function
- Vital Role
- CD16 Expression
- Independent Function
Vγ2Vδ2 (Vδ2) T cells play a vital role in the control of HIV infection. Vδ2 T cells recognize phosphoantigens such as IPP, and they mediate ADCC through FcγRIIIa (CD16). Our goal is to understand how the heterogeneous repertoires of Vδ2 T cells are involved in both phosphoantigen -induced response and ADCC in HIV infection, especially in the early stage of HIV infection.
PBMCs were obtained from a total of 81 subjects, including 18 early, 42 chronic HIV-1 infected subjects (all treatment-naive) and 21 healthy subjects. Cellular immune functions of Vδ2 T cells were analyzed by flow cytometry.
Circulating Vδ2 T cells comprised two functionally diverse subsets which were discriminated by the CD16 expression. Most cytotoxic molecules and IFN-γ were released by CD16- subset (98% in average) after IPP stimulation, while the CD16+ subset was in charge of triggering ADCC via CD16 that was closely related to HIV-associated changes in Vδ2 T cell-mediated ADCC (p< 0.001). In early HIV infection, the CD16- Vδ2 T cells dramatically decreased in comparison with healthy controls (p=0.02), accompanied by the decline of IPP-responsive Vδ2 T cells (p=0.01). Interestingly, a dramatic functional switch of Vδ2 T cell-mediated ADCC with almost reverse profile of the CD107a and IFN-γ expression compared to uninfected group was observed since early HIV infection. Frequency of CD107a+ Vδ2 T cells from early-infected group was significantly higher than that from healthy controls (p<0.05). Although the IPP-activated Vδ2 T cells declined notably in chronic-infected individuals with CD4>500 (cells/μl), the percentage of antibody-dependent cytotoxic Vδ2 T cells was over threefold as high in CD4>500 individuals as in healthy controls (p<0.05 for both).
These data revealed the involvement of two Vδ2 T subsets with different functions during HIV infection and highlighted the plasticity of Vδ2 T cell-mediated ADCC in controlling HIV infection.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.