Loading...
Please wait, while we are loading the content...
Similar Documents
Human Immunodeficiency Virus-driven Expansion of Cd4؉cd25؉ Regulatory T Cells, Which Suppress Hiv-specific Cd4 T- Cell Responses in Hiv-infected Patients T Cell Depletion during All Stages of Hiv Disease Occurs Predominantly in the Gastrointestinal Tract
| Content Provider | Semantic Scholar |
|---|---|
| Author | Church, Joseph A. |
| Abstract | " Naive " CD4 ϩ T cells were lower in the GH-deficient children, as were central memory T cells. In contrast , effector memory CD4 ϩ T cells and effector CD8 ϩ T cells were increased in the GH-deficient children. Conclusions. Thymic and postthymic lymphocyte pathways are impaired in HIV-infected children, and antiret-roviral therapy–associated immune reconstitution is often incomplete. GH might be useful in the management of HIV-infected children with GH deficiency and incomplete immune reconstitution with antiretroviral therapy. Reviewer's Comments. The reasons why some patients respond to antiretroviral therapy more effectively than others is generally unknown. However, this study suggests that some of this variation may be related to the GH axis of the infected patients. Whether GH-replacement therapy will improve the immune reconstitution in GH-deficient subjects awaits clinical trials. Of interest, also, would be the effect of GH treatment on subjects with incomplete immune reconstitution but normal GH-stimulation studies. Purpose of the Study. HIV infection is associated with a progressive decline in CD4 ϩ T-cell numbers. However, multiple mechanisms of HIV-associated T-cell dysfunction have been described, including reduced HIV-specific lymphopro-liferative and cytotoxic T-cell responses and failure to generate proinflammatory cytokines. A CD4 ϩ T-cell subset with regulatory properties has been characterized. These cells, regulatory T cells (Tregs), express CD25 and inhibit the proliferation of T lymphocytes both in vitro and in vivo. This suppression may be antigen specific and cytokine mediated. Methods. Peripheral blood T cells were obtained from clinically stable, antiretroviral-treated HIV-infected individuals with CD4 ϩ T cells Ͼ500/mm 3 and plasma HIV RNA Ͻ50 copies per mL. These cells were used for extensive flow-cytometric analysis, proliferation and suppression assays, and expression of FOXP3, a transcription factor in Tregs. Results. HIV-infected individuals had increased numbers of CD4 ϩ CD25 ϩ T cells with the phenotypic, molecular , and functional characteristics of Tregs. This expanded population persisted despite long-term viral control. Patient Tregs suppressed CD4 ϩ T-cell proliferation to recall antigens and specific HIV proteins. The proliferative capacity of T cells to recall and p24 antigens significantly increased after the depletion of Tregs. Additionally, these T cells responded specifically to p24 antigen with expression of transforming growth factor  and interleukin 10. It is interesting to note that the suppressive activity by the cell population did not depend on secretion of transforming growth factor  or interleukin 10. Conclusions. HIV derives expansion of CD4 ϩ CD25 regulatory T … |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://pediatrics.aappublications.org/content/pediatrics/116/Supplement_2/572.1.full.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
