Effector and regulatory T cells derived from the same T cell clone differ in MHC class II‐peptide multimer binding

Abstract

MHC class II-peptide multimers are a valuable tool for antigen-specific detection of CD4 + T cells. However, it has been proposed that T cells in a hypo-responsive state can have diminished binding of such multimers. In the present study, we investigated this phenomenon at the clonal level. We found that anergic CD4 + T cells had a reduced capacity to bind MHC class II-peptide multimers compared to their non-anergic counterparts. Increasing the incubation temperature, time, or MHC-peptide valency could not equalize multimer binding by anergic and non-anergic T cells. Neither anergic T cells nor non-anergic T cells internalized the MHC class II-peptide dimers efficiently, and in both cases the dimers bound to the plasma membrane at locations containing a low amount of raft-associated lipids. Disruption of lipid rafts, however, led to decreased dimer binding by non-anergic T cells and to a lesser extent by anergic T cells. Finally, we show that the depth of the anergic state of the T cell, which determines its ability to regulate other T cell responses, correlates with the reduced dimer binding. We here demonstrate for the first time differential MHC class II-peptide multimer binding by regulatory (anergic) and effector T cells with identical TCR.Sadly, Chris Broeren passed away December 5, 2003

Naturally acquired tolerance and sensitization to minor histocompatibility antigens in healthy family members

“…These results are in agreement with 2 earlier studies describing reduced HLA/peptide multimer binding by T REG . 17,18 Low avidity CD8 dim staining HY-specific T REG have been described in a murine allograft tolerance model. 30 These observations collectively point to incomplete T-cell receptor signaling as a common feature of T REG function.…”

“…Thus, differences in tetramer staining intensity may indicate the presence of functionally different types of T cells. 17,18 The dominant presence of minor H antigen-specific alloimmune T REG or T CTL in a hematopoietic stem cell (SC) graft may have differential impacts on the outcome of HLA identical minor H antigen nonidentical stem cell transplantation (SCT). As a first step toward understanding how the minor H antigen alloimmunization status of SC donors may affect SCT outcome, we analyzed whether "natural" exposure to fetal or maternal minor H alloantigens induces functionally different T cells in healthy parous female and male blood donors, respectively.…”

HBcAg-specific CD4+CD25+regulatory T cells modulate immune tolerance and acute exacerbation on the natural history of chronic hepatitis B virus infection

“…Increasing evidence indicates that short-term culture of PBMCs with the presence of specific antigen may increase the number of antigenspecific T cells and facilitates tetramer staining, flow cytometry cell sorting, and tracking of these T cells during viral infections [22][23][24][25][26][27]. Culture temperature and activation status of these T cells may also affect the efficiency of tetramer staining [25][26][27].…”

“…Amino acids that are regarded as having a negative effect on the binding ability are given values between )1 and )3. The 17 peptides with 15-mer amino acids used in this study were arbitrarily designed (their SYFPEITHI scores not shown, Supplementary Table 1), of which, P2, LSFLPSDFFP SVRDL (HBcAg [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] ) and P13, PPAYRPPNAPILSTL (HBcAg 129-143 ) had the highest SYFPEITHI scores, i.e., 20 and 28, for DRB1*0401 and DRB1*0101 molecules, respectively. They were used for the construction of each of MHC class II tetramers.…”

“…Preparation of HLA-A2-HBcAg 18-27 tetrameric complexes HLA-A2-restricted epitope peptide HBcAg [18][19][20][21][22][23][24][25][26][27] FLPSDFFPSV, an immunodominant cytotoxic T lymphocyte (CTL) epitope on HBcAg, is currently the most widely used epitope for assaying CTL activities in HBV patients [2,[17][18][19][20][21]. We used HLA-A2-HBcAg 18-27 tetrameric complexes in this study to monitor CTL activities for the correlation with T reg f during AEs in HLA-A2 patients.…”