Elite controllers display higher activation on central memory CD8 T cells than HIV patients successfully on HAART.

T cell activation plays an important role in driving CD4 depletion during the course of HIV infection. There is scarce information about activation of different T cell subsets in HIV(+) individuals experiencing distinct disease progression. The activation of different CD4(+) and CD8(+) T cell subsets and its contribution to total T cell activation were examined measuring CD38 expression by flow cytometry in 120 HIV-infected individuals and 9 uninfected healthy controls. HIV-infected patients were divided into four groups: 11 elite controllers (EC), 14 viremic controllers (VC), 61 antiretroviral-naive typical progressors (TP), and 34 progressors with viral suppression (VS) under antiretroviral therapy. EC displayed significantly greater activation levels than VS, with a higher contribution of central memory subsets to the activation of total CD8 T cells (p = 0.002). The activation of central memory CD8(+) T cells significantly correlated with viral load in TP regardless of CD4 counts. In contrast with VS, proviral load was undetectable in all EC. Compared to VS, EC display abnormal and higher activation levels of different CD8(+) T cell subsets. Factors other than the size of the viral reservoir should explain the high level of activation of central memory CD8(+) T cells characteristically seen in HIV(+) individuals with spontaneous control of viral replication.

Evolution of the functional profile of HIV-specific CD8+ T cells in patients with different progression of HIV infection over 4 years.

There is a lack of information about the stability of these responses over time in subjects experiencing differences in HIV disease progression. The functional profile of Gag-specific and Nef-specific CD8T-cell responses based on the simultaneous production macrophage inflammatory protein (MIP)-1beta, interleukin (IL)-2, and tumor necrosis factor (TNF)-alpha was longitudinally assessed using flow cytometry over 4 years in 8 elite controllers (EC), 8 viremic controllers, 10 antiretroviral-naive typical progressors, and 10 patients with virological suppression (VS) on antiretroviral therapy. CD8 T-cell subsets with 2 functions tended to decline, whereas subsets with 1 function tended to increase over time in typical progressors. In viremic controller, Gag and Nef responses evolved differently. In EC, the functional profile of Gag-specific CD8T-cell responses evolved increasing polyfunctionality over time. Finally, Nef-specific responses in VS increased in the MIP+TNF-IL2- CD8 T-cell subset while Gag-specific responses did not change. The functional profile of HIV-specific CD8T-cell responses may evolve in different ways depending of the targeted HIV protein and the ability to control virus replication. In patients with uncontrolled HIV replication, the functionality of Gag-specific CD8T-cell responses tends to diminish over time, whereas in EC, there is an increase in polyfunctional subsets. Interestingly, VS do not seem to restore the polyfunctional profile of HIV-specific CD8T-cell responses.

Quantification and phenotype of regulatory T cells in rheumatoid arthritis according to disease activity score-28.

Here we studied and characterized different peripheral blood (PB) regulatory T cell (Treg) subsets in rheumatoid arthritis (RA) patients and tested the hypothesis that changes in these cells can be linked to the degree of inflammation and relapsing/remission periods. PB cells were examined from RA subjects (n = 60) with different disease activity score-28 (DAS28) and from healthy controls (n = 40). Frequencies of Treg subsets expressing characteristic membrane antigens, FoxP3 or intracellular cytokines were quantified by flow cytometry. We observed a decrease in the percentages of CD4(+)CD25(high), CD4(+)CD25(int), CD4(+)CD25(int/high)FoxP3(+), CD4(+)CD38(+), CD4(+)CD62L(+), CD8(+)CD25(high)CD45RA(+) and CD8(+)CD25(int)CD45RA(+) T cells in PB of RA patients compared to healthy controls. In addition, we found increased percentages of cells expressing membrane/intracellular regulatory antigens such as OX40 (CD134), CD45RB(low) or CTLA-4 (CD152), and a higher proportion of other T cell subsets including CD4(+)CTLA-4(+), CD4(+)IL10(+), CD4(+)CD25(int)IL10(+), CD4(+)CD25(int) TGFbeta(+), CD4(+)CD25(low) TGFbeta(+) and CD8(+)CD28(- ). We show that most of these changes parallel the intensity of inflammation, with lowest or highest values in patients with moderately/very active disease compared to healthy controls and at times to patients with inactive RA. The balance between these cell subsets and their antigen expression would determine the inflammation levels and could thus be linked to the relapsing/remission periods of the disease.

Osteopontin gene polymorphisms in Spanish patients with rheumatoid arthritis.

OBJECTIVE: Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology characterized by cartilage and bone destruction. The main genetic determinant to RA, the shared epitope, maps to the HLA-DR locus, although this is not the only risk factor. The osteopontin (OPN) gene, with pleiotropic functions in inflammatory and immune responses, has been implicated in the pathogenesis of RA. We studied the association of polymorphisms in the OPN gene and predisposition to RA. METHODS: Analysis was performed in a case-control study with 263 patients and 478 controls. Four single nucleotide polymorphisms (SNP), 327T/C, 795C/T, 1128A/G, and 1284A/C, of the OPN gene were genotyped by primer-specific amplification in the presence of SYBR Green. RESULTS: Distorted transmission of these polymorphisms was studied in 58 RA trios and 61 affected sibling pairs. These SNP demonstrated strong linkage disequilibrium. No statistically significant association was observed (80% power to exclude a genotypic relative risk of 1.49 at the 5% significance level, with minor allele frequencies of 28%). This lack of association with RA was found after stratification for the shared epitope as well. CONCLUSION: Our data suggest that, unlike the reported effect of the OPN SNP conferring predisposition to common diseases such as multiple sclerosis or systemic lupus erythematosus, these OPN gene polymorphisms do not contribute to RA susceptibility in the Spanish population we studied.