RationalePork-Cat syndrome is an IgE-mediated reaction in patients with specific IgE to mammalian serum albumins, most commonly pork and to date these cases have only been reported from Europe. We describe 6 patients with food induced hypersensitivity syndromes ranging from oral pruritus to anaphylaxis. Their serum contained IgE antibodies to albumin from several species and was evaluated for cross-reactivity.MethodsPatients with a history of allergic reactions to meat were enrolled into an IRB approved study with informed consent. IgE antibodies were determined to select mammalian meats and albumins. Values less than 0.35 kU/L were considered negative. Inhibition assays were performed with porcine and feline serum albumin by mixing 100ul of patient serum with 7mg of feline or porcine albumin in PBS and specific IgE assays were repeated.ResultsOur 6 patients with allergic reactions to mammalian meat had serum IgE specific for feline and porcine albumin as well as for cat dander and pork. Five of six were negative for IgE specific to galactose-alpha-1,3-galactose. Pork albumin produced complete inhibition of IgE to pork and pork albumin and incomplete inhibition of IgE to cat dander and cat albumin. Cat albumin produced significant inhibition of IgE to pork, cat albumin, and pork serum albumin but not cat dander.ConclusionsSome patients with meat hypersensitivity have IgE to cat albumin. The structure of albumin is highly conserved through mammalian species which likely accounts for the cross-reactivity with pork and other meat albumins. RationalePork-Cat syndrome is an IgE-mediated reaction in patients with specific IgE to mammalian serum albumins, most commonly pork and to date these cases have only been reported from Europe. We describe 6 patients with food induced hypersensitivity syndromes ranging from oral pruritus to anaphylaxis. Their serum contained IgE antibodies to albumin from several species and was evaluated for cross-reactivity. Pork-Cat syndrome is an IgE-mediated reaction in patients with specific IgE to mammalian serum albumins, most commonly pork and to date these cases have only been reported from Europe. We describe 6 patients with food induced hypersensitivity syndromes ranging from oral pruritus to anaphylaxis. Their serum contained IgE antibodies to albumin from several species and was evaluated for cross-reactivity. MethodsPatients with a history of allergic reactions to meat were enrolled into an IRB approved study with informed consent. IgE antibodies were determined to select mammalian meats and albumins. Values less than 0.35 kU/L were considered negative. Inhibition assays were performed with porcine and feline serum albumin by mixing 100ul of patient serum with 7mg of feline or porcine albumin in PBS and specific IgE assays were repeated. Patients with a history of allergic reactions to meat were enrolled into an IRB approved study with informed consent. IgE antibodies were determined to select mammalian meats and albumins. Values less than 0.35 kU/L were considered negative. Inhibition assays were performed with porcine and feline serum albumin by mixing 100ul of patient serum with 7mg of feline or porcine albumin in PBS and specific IgE assays were repeated. ResultsOur 6 patients with allergic reactions to mammalian meat had serum IgE specific for feline and porcine albumin as well as for cat dander and pork. Five of six were negative for IgE specific to galactose-alpha-1,3-galactose. Pork albumin produced complete inhibition of IgE to pork and pork albumin and incomplete inhibition of IgE to cat dander and cat albumin. Cat albumin produced significant inhibition of IgE to pork, cat albumin, and pork serum albumin but not cat dander. Our 6 patients with allergic reactions to mammalian meat had serum IgE specific for feline and porcine albumin as well as for cat dander and pork. Five of six were negative for IgE specific to galactose-alpha-1,3-galactose. Pork albumin produced complete inhibition of IgE to pork and pork albumin and incomplete inhibition of IgE to cat dander and cat albumin. Cat albumin produced significant inhibition of IgE to pork, cat albumin, and pork serum albumin but not cat dander. ConclusionsSome patients with meat hypersensitivity have IgE to cat albumin. The structure of albumin is highly conserved through mammalian species which likely accounts for the cross-reactivity with pork and other meat albumins. Some patients with meat hypersensitivity have IgE to cat albumin. The structure of albumin is highly conserved through mammalian species which likely accounts for the cross-reactivity with pork and other meat albumins.

RationaleSera from healthy donors of A and O blood types have high levels of IgG antibodies to galactose-alpha-1,3-galactose (alpha-gal), whereas donors of type B or AB blood contain significantly less circulating anti-gal. This is presumably due to the structural similarity of B blood type antigen and alpha-gal. Thus, we hypothesized that blood type B or AB could be protective against the development of IgE to alpha-gal.MethodsSera were collected as part of several ongoing studies, each with IRB approval. Individual serum samples (n=1047) were "back" typed in the laboratory using standard reagent red blood cells of either A or B type. Agglutination reaction was observed for 5 minutes at 30 C. A logistic regression model was used to assess correlation between blood type and IgE to alpha-gal. A Bonferroni adjustment was used for multiple comparisons in blood types.ResultsThere was no significant association between blood type and sIgE to alpha-gal (p = 0.19). Subjects with B/AB blood types constituted 140 of the 1047 samples analyzed (13.4%) and of these, 55 had IgE to alpha-gal (10.1% of positive samples). Within the US, prevalence of blood type B / AB ∼15%. No correlation was found for blood type and gender, sIgE to beef, tick exposure or subset of symptoms.ConclusionsDespite preliminary reports, there does not appear to be an association between blood type and the development of IgE to alpha-gal. Further studies are aimed at assessing the avidity of the IgE response to alpha-gal between subjects of different blood types. RationaleSera from healthy donors of A and O blood types have high levels of IgG antibodies to galactose-alpha-1,3-galactose (alpha-gal), whereas donors of type B or AB blood contain significantly less circulating anti-gal. This is presumably due to the structural similarity of B blood type antigen and alpha-gal. Thus, we hypothesized that blood type B or AB could be protective against the development of IgE to alpha-gal. Sera from healthy donors of A and O blood types have high levels of IgG antibodies to galactose-alpha-1,3-galactose (alpha-gal), whereas donors of type B or AB blood contain significantly less circulating anti-gal. This is presumably due to the structural similarity of B blood type antigen and alpha-gal. Thus, we hypothesized that blood type B or AB could be protective against the development of IgE to alpha-gal. MethodsSera were collected as part of several ongoing studies, each with IRB approval. Individual serum samples (n=1047) were "back" typed in the laboratory using standard reagent red blood cells of either A or B type. Agglutination reaction was observed for 5 minutes at 30 C. A logistic regression model was used to assess correlation between blood type and IgE to alpha-gal. A Bonferroni adjustment was used for multiple comparisons in blood types. Sera were collected as part of several ongoing studies, each with IRB approval. Individual serum samples (n=1047) were "back" typed in the laboratory using standard reagent red blood cells of either A or B type. Agglutination reaction was observed for 5 minutes at 30 C. A logistic regression model was used to assess correlation between blood type and IgE to alpha-gal. A Bonferroni adjustment was used for multiple comparisons in blood types. ResultsThere was no significant association between blood type and sIgE to alpha-gal (p = 0.19). Subjects with B/AB blood types constituted 140 of the 1047 samples analyzed (13.4%) and of these, 55 had IgE to alpha-gal (10.1% of positive samples). Within the US, prevalence of blood type B / AB ∼15%. No correlation was found for blood type and gender, sIgE to beef, tick exposure or subset of symptoms. There was no significant association between blood type and sIgE to alpha-gal (p = 0.19). Subjects with B/AB blood types constituted 140 of the 1047 samples analyzed (13.4%) and of these, 55 had IgE to alpha-gal (10.1% of positive samples). Within the US, prevalence of blood type B / AB ∼15%. No correlation was found for blood type and gender, sIgE to beef, tick exposure or subset of symptoms. ConclusionsDespite preliminary reports, there does not appear to be an association between blood type and the development of IgE to alpha-gal. Further studies are aimed at assessing the avidity of the IgE response to alpha-gal between subjects of different blood types. Despite preliminary reports, there does not appear to be an association between blood type and the development of IgE to alpha-gal. Further studies are aimed at assessing the avidity of the IgE response to alpha-gal between subjects of different blood types.

RATIONALE: The extent to which rhinovirus (RV) provokes airway inflammation contributing to asthma exacerbations is not clear. METHODS: Children (7 through 12 years old) were enrolled in the emergency room (ER) at the main tertiary care hospital for children in Costa Rica: 94 with acute wheezing and 183 non-wheezing controls, including 44 with stable asthma (SA). Nasal washes were obtained to test for RV by RT-PCR and for eosinophil cationic protein (nECP). Total IgE levels and expired nitric oxide (FeNO) were also assessed. RESULTS: Positive tests for RV in nasal washes were significantly increased among wheezing children compared to controls, or those with SA: 64%, 15%, and 13%, p<0.001 and p<0.001, respectively. Geometric mean [GM] levels for total IgE among asthmatic children (482 IU/ml) were higher than for controls (136 IU/ml, p<0.001), but similar among the 3 asthmatic groups (RV+ wheezing, n=61, RV- wheezing, n=33, and SA's, n=44). The values [GM] for nECP were similar among the RV+, and RV-, wheezing children and the SA's (151,139, and 118 ng/ml, respectively). These values were significantly increased compared to controls (60ng/ml, n=139; p<0.025 compared to all 3 asthmatic groups). In contrast, FeNO levels [GM] were significantly higher among RV+ wheezing children compared to those who were RV- (39 vs 28 ppb, respectively, p=0.04), or compared to those with SA (25 ppb, p=0.02) or controls (15 ppb, p<0.001). CONCLUSIONS: Among children treated for asthma exacerbations in the ER, levels of FeNO, but not nECP, were significantly higher among those who tested positive for rhinovirus.

RATIONALE: IgG antibodies to the carbohydrate, galactose-α-1,3-galactose (alpha-gal), are found in sera from all immunocompetent humans. Patients with type B blood have significantly less IgG to alpha-gal. Alpha-gal has recently been described as a novel food allergen and patients with IgE to alpha-gal report delayed anaphylaxis occurring 3-6 hours after eating mammalian meat. We hypothesize that B blood type will be negatively associated with IgE to alpha-gal due to the structural similarity between B blood group substance and the alpha-gal moiety. METHODS: Serum was collected from patients (n=266) from the University of Virginia Allergy Clinic. Immunoassays were performed for IgE to alpha-gal and sera were back-typed with red blood cells. RESULTS: A logistic regression model and Wald Chi-square was used to assess if there was an association between blood types and IgE, and odds ratio was used to quantify the effect of different blood types. A Bonferroni adjustment was employed to adjust for multiple comparisons in blood types. There was a significant difference between blood types and the presence of IgE to alpha-gal (p = 0.012). Subjects with B/AB blood were only 0.11 likely to be IgE positive compared with blood type A subjects (95% CI: 0.02 to 0.60, p = 0.004), and were also 0.11 likely to be IgE positive compared with blood type O subjects (95% CI: 0.02 to 0.59, p = 0.003). CONCLUSIONS: Subjects with B blood group were less likely to develop IgE to alpha-gal. Thus, type B/AB may confer a protective effect on the development of IgE to alpha-gal.