{'fraction_non_alphanumeric': 0.03262955854126679, 'fraction_numerical': 0.009596928982725527, 'mean_word_length': 5.8, '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': 2, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Cross‐Clade HIV‐1‐Specific Neutralizing IgA in Mucosal and Systemic Compartments of HIV‐1‐Exposed, Persistently Seronegative Subjects

Summary: There is an urgent need for a universally effective HIV‐1 vaccine, but whether a vaccine will be able to protect against HIV‐1 of different clades is a significant concern. IgA from HIV‐1‐exposed, persistently seronegative (HEPS) subjects has been shown to neutralize HIV‐1 and to block epithelial HIV‐1 transcytosis, and it may target novel HIV‐1 epitopes. We have tested the ability of plasma and mucosal IgA purified from HEPS subjects to neutralize HIV‐1 primary isolates of different viral clades and phenotypes. IgA from two groups of HEPS subjects was tested: sex workers from Nairobi, Kenya, where clades A and D predominate, and the heterosexual partners of individuals infected by clade B virus. HIV‐1‐infected and low‐risk uninfected individuals were included as controls. IgA purified from the blood, genital tract, and saliva of most HEPS sex workers demonstrated significant crossclade HIV‐1 neutralization, whereas a more clade‐restricted pattern of neutralization was found in partners of clade B‐infected individuals. IgA purified from HIV‐1‐infected individuals also mediated cross‐clade neutralization, whereas IgA from uninfected controls lacked neutralizing activity. In conclusion, mucosal and plasma IgA from HEPS subjects neutralizes HIV‐1 of different clades. This ability to induce HIV‐1‐specific systemic and mucosal IgA may be an important feature of an effective prophylactic HIV‐1 vaccine.