- Email: [email protected]
145 The major cross-reactive allergen of imported fire ant venom
142
143
EVALUATION OF COMMERCIAL IMPORTED FIRE ANT (IFA) WHOLE BODY EXTRACTS (IFAWBE). Brian T. Butcher, PhD, and Margaret A. Reed, MS, New Orleans, LA. IFAWBE from three major US suppliers (Center, Greer, Hollister-Stier) were compared with a reference IFAWBE and IFA venom (IFAV) by crossed immunoelectrophoresis (CIE) and RAST inhibition. Prior to testing, all preparations were adjusted CIE showed marked to a standard protein content. differences in antigenic content between IFAWBE No commercial IFAWBE from different suppliers. RAST inhibition contained all IFAV antigens. extract had results showed that no commercial equivalent to reference inhibitory activity Reference IFAWBE gave 50% IFAWBE or IFAV. inhibition of IFAWBE and IFAV RAST at 52 and 492 protein/ml respectively. IFAV gave 50% w inhibition of IFAWBE and IFAV RAST at 5.9 and 58 ug/ml respectively. Only one commercial extract of IFAWBE RAST and none reached 50% inhibition of gave 50% inhibition of IFAV RAST. Evaluation RAST inhibition slopes and intercepts confirmed qualitative and quantitative differences among IFA preparations. All reference and commercial lo-fold less commercial IFAWBE had at least inhibitory activity than reference IFAWBE and at least loo-fold less than IFAV; two extracts from supplier had no significant one commercial inhibitory activity. Our findings suggest possible reasons why some IFA-allergic individuals fail to respond to testing or immunotherapy with commercial IFAWBE need for standardization of and show an urgent IFAWBE extracts for diagnosis and treatment of IFA sensitivity.
144
LACK OF CROSS-REACTIVITY BETWEEN IMPORTED FIRE ANT VENOM (IFAV) AND OTHER HYMENOPTERAVENOMS. Dane11 J. Watkins, BS, Margaret A Reed, MS, and Brian T. Butcher, PhD. New Orleans, LA. Venoms from imported fire ant (IFAV) and other Hymenoptera both contain phospholipase A (PLA). While PLA has been shown to be the allergen responsible for allergic reactions to other Hymenoptera, its role in IFA allergy remains to be confirmed. Reports of allergic reactions in individuals on first IFA sting have raised the possibility of cross-reactivity between IFA venom (IFAV) and venoms of other Hymenoptera. We evaluated antigenic cross-reactivity by crossed immunoelectrophoresis with hyperimmune (CIE) polyclonal rabbit anti-IFAV antiserum and used IFAV RAST inhibition as a measure of allergenic cross-reactivity. Hymenoptera venom proteins were from Honey Bee, Wasp, White-Faced Hornet, purchased Yellow Jacket, and Yellow Hornet, commercially. IFAV gave 3 immunoprecipitin lines on CIE. No precipitin lines were obtained with venom proteins from other Hymenoptera. RAST inhibition studies of IFAV RAST using a pool of IFAV specific human sera, with mean IFAV RAST % binding of 26%, showed that IFAV gave maximal inhibition at 1 mg protein/ml and 50% inhibition at 100 ug/ml. No significant inhibition of IFAV RAST was obtained with any of the venoms from other Hymenoptera. These results indicate that IFAV or other Hymenoptera venoms do not have shared antigenic or allergenic epitopes. The reports of allergic reactions to first IFA sting remain to be explained.
145
204
Five groups of patients were studied to determine the relationship between imported fire ant reactivity and reactivity to bee and vespid venoms. The first group consisted of 100 adults who had no history of insect allergy and no known exposure to FA. Sera from this group gave a mean FAV rast of 0.89% with a maximum of 1.6% binding. Group 2 consisted of 21 adults with no history of stinging insect allergy who lived in an area of high FA exposure. 24% of this group was RAST positive to FAV. Group 3 was 37 patients with systemic reactions to IFA stings. This group was 100% RAST positive to FAV and 46% of them were positive to bee and/or vespids. Group 4 consisted of 68 bee and/or vespid allergic patients with no exposure to FA. 51% of this group was positive to FAV. Group 5 included 23 patients allergic to bee and/or vespid venoms from an area with high FA exposure. 87% of this group was RAST positive to fire ant. FAV RAST positive patients in groups 2 and 5 were also skin test positive. RAST inhibition studies were attempted with a number of sera showing strong reactivity to both FAV and bee and/or vespid venoms. In some cases it was possible to demonstrate dose dependent inhibition of IgE binding. In electrophoretic immunoblot studies sera from patients without FA exposure showed binding to only one of the FAV bands, and sera from patients with exposure to FA showed various patterns of binding.
THE MAJOR CROSS-REACTIVE ALLERGEN OF IMPORTED FIRE ANT VENOM. Dalton E. Dove and Donald R. Hoffman, Ph.D. Greenville North Carolina It has been reoorted that manv oatients who are allergic to'bee and vespid"wasp venoms Sera also react to imported fire ant venom. from patients known to be allergic to bees and/ or vespid wasps, who had no known exposure to imported fire ants and lived in areas remote from the range of the imported fire ant were studied to identify the cross-reactive Membranes were component(s) in fire ant venom. prepared from acidic buffer, non-denaturing Strips were electrophoresis of fire ant venom. incubated in serum from various patients and then with 125-I-anti-IgE. Sera from patients with known fire ant exposure showed several patterns of reactivity with the fire ant venom, while sera from yellow jacket allergic patients without fire ant exposure showed binding to the single band, which had the highest molecular Sera from insect weight of the major bands. allergic patients without fire ant exposure were tested by RAST using the four highly purified important allergens from fire ant venom. These sera were all specific for Sol i I, the largest allergen. This was true for both bee and vespid specific sera from the northeastern and southwestern United States. Sol i I has an apparent native molecular weight of 37000. On SDS-PAGE there are three bands at 18000, 16500 and 14000. High performance cation exchange chromatography shows 3 forms of differing charge eluting from a Mono S column at 0.16, 0.24 and 0.31M NaCl. Sol i I did not have any of the enzyme activities cotmnonly found in venoms.
143
EVALUATION OF COMMERCIAL IMPORTED FIRE ANT (IFA) WHOLE BODY EXTRACTS (IFAWBE). Brian T. Butcher, PhD, and Margaret A. Reed, MS, New Orleans, LA. IFAWBE from three major US suppliers (Center, Greer, Hollister-Stier) were compared with a reference IFAWBE and IFA venom (IFAV) by crossed immunoelectrophoresis (CIE) and RAST inhibition. Prior to testing, all preparations were adjusted CIE showed marked to a standard protein content. differences in antigenic content between IFAWBE No commercial IFAWBE from different suppliers. RAST inhibition contained all IFAV antigens. extract had results showed that no commercial equivalent to reference inhibitory activity Reference IFAWBE gave 50% IFAWBE or IFAV. inhibition of IFAWBE and IFAV RAST at 52 and 492 protein/ml respectively. IFAV gave 50% w inhibition of IFAWBE and IFAV RAST at 5.9 and 58 ug/ml respectively. Only one commercial extract of IFAWBE RAST and none reached 50% inhibition of gave 50% inhibition of IFAV RAST. Evaluation RAST inhibition slopes and intercepts confirmed qualitative and quantitative differences among IFA preparations. All reference and commercial lo-fold less commercial IFAWBE had at least inhibitory activity than reference IFAWBE and at least loo-fold less than IFAV; two extracts from supplier had no significant one commercial inhibitory activity. Our findings suggest possible reasons why some IFA-allergic individuals fail to respond to testing or immunotherapy with commercial IFAWBE need for standardization of and show an urgent IFAWBE extracts for diagnosis and treatment of IFA sensitivity.
144
LACK OF CROSS-REACTIVITY BETWEEN IMPORTED FIRE ANT VENOM (IFAV) AND OTHER HYMENOPTERAVENOMS. Dane11 J. Watkins, BS, Margaret A Reed, MS, and Brian T. Butcher, PhD. New Orleans, LA. Venoms from imported fire ant (IFAV) and other Hymenoptera both contain phospholipase A (PLA). While PLA has been shown to be the allergen responsible for allergic reactions to other Hymenoptera, its role in IFA allergy remains to be confirmed. Reports of allergic reactions in individuals on first IFA sting have raised the possibility of cross-reactivity between IFA venom (IFAV) and venoms of other Hymenoptera. We evaluated antigenic cross-reactivity by crossed immunoelectrophoresis with hyperimmune (CIE) polyclonal rabbit anti-IFAV antiserum and used IFAV RAST inhibition as a measure of allergenic cross-reactivity. Hymenoptera venom proteins were from Honey Bee, Wasp, White-Faced Hornet, purchased Yellow Jacket, and Yellow Hornet, commercially. IFAV gave 3 immunoprecipitin lines on CIE. No precipitin lines were obtained with venom proteins from other Hymenoptera. RAST inhibition studies of IFAV RAST using a pool of IFAV specific human sera, with mean IFAV RAST % binding of 26%, showed that IFAV gave maximal inhibition at 1 mg protein/ml and 50% inhibition at 100 ug/ml. No significant inhibition of IFAV RAST was obtained with any of the venoms from other Hymenoptera. These results indicate that IFAV or other Hymenoptera venoms do not have shared antigenic or allergenic epitopes. The reports of allergic reactions to first IFA sting remain to be explained.
145
204
Five groups of patients were studied to determine the relationship between imported fire ant reactivity and reactivity to bee and vespid venoms. The first group consisted of 100 adults who had no history of insect allergy and no known exposure to FA. Sera from this group gave a mean FAV rast of 0.89% with a maximum of 1.6% binding. Group 2 consisted of 21 adults with no history of stinging insect allergy who lived in an area of high FA exposure. 24% of this group was RAST positive to FAV. Group 3 was 37 patients with systemic reactions to IFA stings. This group was 100% RAST positive to FAV and 46% of them were positive to bee and/or vespids. Group 4 consisted of 68 bee and/or vespid allergic patients with no exposure to FA. 51% of this group was positive to FAV. Group 5 included 23 patients allergic to bee and/or vespid venoms from an area with high FA exposure. 87% of this group was RAST positive to fire ant. FAV RAST positive patients in groups 2 and 5 were also skin test positive. RAST inhibition studies were attempted with a number of sera showing strong reactivity to both FAV and bee and/or vespid venoms. In some cases it was possible to demonstrate dose dependent inhibition of IgE binding. In electrophoretic immunoblot studies sera from patients without FA exposure showed binding to only one of the FAV bands, and sera from patients with exposure to FA showed various patterns of binding.
THE MAJOR CROSS-REACTIVE ALLERGEN OF IMPORTED FIRE ANT VENOM. Dalton E. Dove and Donald R. Hoffman, Ph.D. Greenville North Carolina It has been reoorted that manv oatients who are allergic to'bee and vespid"wasp venoms Sera also react to imported fire ant venom. from patients known to be allergic to bees and/ or vespid wasps, who had no known exposure to imported fire ants and lived in areas remote from the range of the imported fire ant were studied to identify the cross-reactive Membranes were component(s) in fire ant venom. prepared from acidic buffer, non-denaturing Strips were electrophoresis of fire ant venom. incubated in serum from various patients and then with 125-I-anti-IgE. Sera from patients with known fire ant exposure showed several patterns of reactivity with the fire ant venom, while sera from yellow jacket allergic patients without fire ant exposure showed binding to the single band, which had the highest molecular Sera from insect weight of the major bands. allergic patients without fire ant exposure were tested by RAST using the four highly purified important allergens from fire ant venom. These sera were all specific for Sol i I, the largest allergen. This was true for both bee and vespid specific sera from the northeastern and southwestern United States. Sol i I has an apparent native molecular weight of 37000. On SDS-PAGE there are three bands at 18000, 16500 and 14000. High performance cation exchange chromatography shows 3 forms of differing charge eluting from a Mono S column at 0.16, 0.24 and 0.31M NaCl. Sol i I did not have any of the enzyme activities cotmnonly found in venoms.