{'fraction_non_alphanumeric': 0.02314540059347181, 'fraction_numerical': 0.020771513353115726, 'mean_word_length': 4.813793103448276, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Cytotoxic T-lymphocyte response induced by a V3 loop synthetic peptide from an African HIV-1 isolate is cross-reactive against HIV-1 strains from North America/Europe region.

Findings are reported from an investigation of cytotoxic T lymphocyte (CTL) induction by a V3-loop peptide from HIV-1 Z321 representative of subtype A isolates from Africa. The Z321 isolate was obtained from a 1976 Zairian blood sample one of the oldest collected samples of HIV-1. Selecting a 15 amino-acid peptide from the V3 loop of the isolate the authors observed efficient and reproducible induction of specific CTL with a single immunization by the peptide. Cross-reactivity was also observed against targets sensitized with V3-loop peptides from HIV-1 isolates MN SC RF and CDC4 all belonging to subtype B. In general the cross-reactivity was observed only when the peptides within the 15 amino-acid region exhibited a tyrosine or a conservative substitution at position 11 and the H-2D binding motif G-P-X-R-X-F corresponding to amino-acid positions 568 and 10 respectively. Study data support a previous report showing cross-reactivity of the CTL primed by V3-loop peptides from subtype B isolates against those from HIV-1 strains belonging to subtypes A D and U. The data together suggest that at least in the V3 loop region the sequences representative of subtypes A and B are immunologically similar such that there is considerable CTL cross-reactivity. Therefore although attempts to prime antibody responses have shown little success at neutralizing heterologous viral species targeting the cell-mediated immune response for induction of HIV-specific CTL may allow for broader cross-reactivity.