ON THE ALLERGENICITY OF HEV-B-1 AMONG HEALTH-CARE WORKERS AND PATIENTS WITH SPINA-BIFIDA ALLERGIC TO NATURAL-RUBBER LATEX

Background: Recent studies have caused much controversy about the prev alence of IgE antibodies to Hev b 1 among health care workers (HCWs) a nd patients with spina bifida (SB) who are allergic to latex. This inv estigation was carried out to verify the results reported. Method: Ser um samples from 140 patients with SB as well as from 105 HCWs allergic to latex were tested by enzyme allergosorbest test (EAST) and EAST-in hibition assay to evaluate the rate and degree of sensitization to hig hly purified Hev b 1. Results: Eighty-one percent of patients with SB who were allergic to latex had IgE antibodies against Hev b 1. The pre valence of anti-Hev b 1 antibodies among HCWs allergic to latex was 52 .3%. In 15 of 33 serum samples from patients with SB that were randoml y tested, the IgE binding to commercial latex allergens could be compl etely inhibited by Hev b 1; in only six cases was the maximum inhibiti on of IgE binding to latex by Hev b 1 less than 50%. Testing two monoc lonal anti-Hev b 1 antibodies with extracts of five brands of latex gl oves revealed a predominant presence of Hev b 1 protein as a monomer o r its aggregates. Molecular analysis of human leukocyte antigen-D regi on genes DRB and DQB1 suggested no statistically significant correlati on between the human leukocyte antigen alleles tested and IgE responsi veness to Hev b 1. Conclusions: Our results indicate that Hev b 1 not only makes significant contributions to the IgE binding to latex, but it is also the unique sensitizer in about 45% of patients with SB who are allergic to latex.