Table II.

Repertoire diversity of UH48 p24-specific CD4+ T cell clones

CloneTCR VβaRecognition SequencebRestricting HLAc
65.2KIVRMYSPT (272–280)DRβ1*0101
1017ETINEEAAEWDRVHPVHA (203–220)DRβ1*0101
3B4PKEPFRDYV (289–297)DQ 5
3D6DR 15/51
3G7EWDRVHPVHA (211–220)DRβ1*0101
4E10EWDRVHPVHA (211–220)DRβ1*0101
4F5EVIPMFSALS (167–176)DRβ1*0101
5D82EEKAFSPEV (160–168)DQ 5
6C102PIVQNIQGQ (133–141)DRβ1*0101
8F105.1EQIGWMTN (245–252)DRβ1*0101
  • a Determined by flow cytometry after staining with Vβ-specific mAbs. Dashes indicate that all CD4+ cells within the clone stained negatively for all TCR Vβ regions tested.

  • b Determined by proliferation assays using overlapping p24 peptides (see Fig. 2) and expressed as the amino acid sequence common to every peptide against which the clone reacted. Amino acid positions of these sequences within the complete HIV-1 HXB2 Gag sequence are shown in parentheses. Note that the Gag sequence spanning aa 381–400, recognized by clones 1A7 and 5A6, is downstream of p24. Because clones 10, 1A7, 5A6, and 9E5 were not mapped using 13-aa peptides, their recognition sequences are the sequences of the larger peptides to which they reacted in initial trials. Dashes, not determined.

  • c Determined by proliferation assays using HLA-blocking Abs and partially HLA-matched APC lines (see Fig. 3). DR15/51 indicates that restriction by the DRβ1*1501 allele or the linked DR51 allele could not be distinguished in the assays performed.