Tick Bites From Amblyomma Americanum As A Major Cause Of Ige Antibodies Specific To Galactose-α-1,3-galactose

AB28 Abstracts

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Anisakis Simplex and Ascaris Lumbricoides Inhibit the Allergic Response to Peanut in a Murine Model of Anaphylaxis A. La Rotta, Y. Higaki, G. Marcos, J. Kilimajer, J. M. Zubeldia, M. L. Baeza; H.G.U. Gregorio Maran˜o´n, Madrid, SPAIN. RATIONALE: Helminths are thought to interfere on the immunologic response to common antigens through the induction of IL-10. However, ambivalent epidemiological data have been presented depending on the parasite. We aimed to explore the modulatory effect of two helminths on anaphylaxis. METHODS: Thirty-six five-week-old C3H/HeJOu mice were subcutaneously sensitized with peanut in the presence of alum. Of those, two groups of 12 were additionally treated daily with intraperitoneal Anisakis simplex (A.s.) or Ascaris lumbricoides (A.l.) somatic extracts. Specific IgG1 and IgG2a, as well as specific IgE were measured. On week 5 mice were challenged with peanut. Anaphylaxis was evaluated by the recognition of clinical symptoms and body temperature changes every five minutes. RESULTS: All peanut sensitized mice induced specific immunoglobulins and developed anaphylactic symptoms upon antigen challenge. Interestingly, A.s. and A.l. treatment reduced specific IgG1 by 23,3% and 32,2% (A.s.) and by 57,54% and 48,7% (A.l.) on week 4 and 5, respectively. Both parasitic extracts also provided a significant inhibition of the anaphylactic symptoms score 20 minutes after challenge (2,87 6 0,012, 1,43 6 0,2 and 0,62 6 0,52 (mean 6 SEM), in non-treated, A.s. treated and A.l. treated mice respectively (p 23 hrs after FIA event was recommended by 52 (73%). Only 43(61%) recommended consultation with an allergist for FIA. In clinic, self-injectable epinephrine (SIE) was recommended by 47(68%) after an anaphylaxis event from any cause, but 98% if bee sting or FIA. Epi-Pen (94%) was preferred over Twinject. Responsibility of SIE teaching was assigned to physicians/nurses 39 (82.9%), allergists 2 (4.2%), self education 3(6.4%) and to pharmacists 3 (6.4%) respectively. Medic-alerts for FIA were prescribed by 29(43%). Practicing physicians sought referral to an allergist more often than intraining physicians (p 5 0.02). Physicians who prescribed SIE were more likely to prescribe medic-alerts (p < 0.01) and seek allergists consultation (p < 0.001). CONCLUSIONS: Deficits in management of FIA in adults exist. Allergists need to improve communications with internists to improve self management skills of patients with FIA.

J ALLERGY CLIN IMMUNOL FEBRUARY 2010

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Sensitization is Related to Exposition in Hymenoptera Venom Allergy Studied in the Valencia Fire Brigade of Spain J. Fernandez1, R. Cabrera2, J. M. Alvarez3, D. Orozco1; 1Miguel Herna´ndez University, San Juan de Alicante, SPAIN, 2Dr. Peset Hospital, Valencia, SPAIN, 3Valencia Fire Brigade, Valencia, SPAIN. RATIONALE: Study the prevalence of hymenoptera venom allergy in the fire brigade of Valencia in Spain, and in firemen who used to remove nests. METHODS: 390 firemen out of 450 answered a questionnaire carried out by a physician to know the characteristics of the sting reactions in their job. Only 51 used to remove nests. Total IgE, skin tests and CAP to the three hymenoptera (Apis mellifera, Vespula germanica and Polistes dominulus) responsible of the most reactions in our area were made. RESULTS: The mean age was 42.94 6 10.07 years (range 26-64). 65 firemen (16.67%) suffer from large local reactions (LLR) and 14 (3.59%) from systemic reactions (SR). Skins tests were positive in 72.13% (71) of the cases. Most of them were positive to a single venom (39.47% to Bee, 26.31% to Polistes and 7.9% to Vespula) and another 26.31% were positive to more than one venom. But in a control group (100 firemen without reaction) only 15% were skin tests positive to any venom. In the sample of 51 most exposed firemen, there were 16(31.4) with clinical reactions, 4 SR (7.82%) and 12 LLR (23.53%), most of them with skin tests or CAP positive. CONCLUSIONS: Although the prevalence of systemic reactions in the fire brigade of Valencia is high, the most exposed firemen, who usually remove nests, have double sensitisation than the whole sample.

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Tick Bites From Amblyomma Americanum As A Major Cause Of Ige Antibodies Specific To Galactose-a-1,3-galactose H. James1, S. Commins1, J. Hosen1, P. Cooper2, K. Kocan3, T. PlattsMills1; 1Asthma and Allergic Diseases Center, University of Virginia Health System, Charlottesville, VA, 2Instituto de Microbiologia, Universidad San Francisco de Quito, Quito, ECUADOR, 3Department of Veterinary Pathobiology, Oklahoma State University, Stillwater, OK. RATIONALE: The high prevalence of IgE to galactose-a-1,3-galactose (alpha-gal) in Virginia, North Carolina, Tennessee, Arkansas, Oklahoma, and Missouri correlates with an area where tick bites are common. METHODS: Using a modified ImmunoCAP assay, we measured IgE to biotinylated proteins from two tick species, A. americanum and D. variabilis. Sera were obtained from three subjects who had experienced extensive tick bites, 100 subjects who presented with delayed anaphylaxis to red meat and were found to have IgE to alpha-gal, and from 60 children living in rural Ecuador. Ticks for extracts were obtained from OSU Tick Rearing Facility. RESULTS: Two of the three subjects who developed IgE to alpha-gal also developed IgE to A. americanum, the species responsible for the bites. Among the 100 alpha-gal positive subjects, 93% reported a recent episode of tick bites and 60% had detectable IgE to A. americanum. Only 15% had detectable IgE to D. variabilis. In Virginia, serum titers of tick IgE have been observed up to 11 IU/ml. In a cohort of children from rural Ecuador, higher titer IgE to tick has been observed (38.5 IU/ml). Although the presence of IgE to tick correlates closely with IgE to alpha-gal, there was only a weak quantitative correlation (r 5 0.234, p 5 0.014). Absorption experiments confirmed that the IgE to tick antigens cannot be explained by IgE to alpha-gal. CONCLUSION: The evidence strongly suggests that ticks, primarily A. americanum, are an important cause of IgE antibodies to alpha-gal and can also induce IgE to tick protein.