ABSTRACT
BACKGROUND: Post-transplant food allergy (LTFA) is increasingly observed after paediatric liver transplantation (LT). Although the immunopathology of LTFA remains unclear, immunoglobulin (Ig) E seems to be implicated. OBJECTIVE: To study humoral and cellular immunity in paediatric LT patients in search for factors associated with LTFA, and compare with healthy controls (HC) and non-transplant food-allergic children (FA). METHODS: We studied serum Ig levels in 29 LTFA, 43 non-food-allergic LT patients (LTnoFA), 21 FA patients and 36 HC. Serum-specific IgA and IgE against common food allergens in LTFA, IgA1 , IgA2 and joining-chain-containing polymeric IgA (pIgA) were measured. Peripheral blood mononuclear cells were analysed by flow cytometry for B and T cell populations of interest. RESULTS: Serum IgA and specific IgA were higher in LTFA compared to LTnoFA. LTFA patients had the highest proportion of circulating T follicular helper cells (cTfh). The percentage of cTfh correlated positively with serum IgA. Unique in LTFA was also the significant increase in serum markers of mucosal IgA and the decrease in the Th17 subset of CXCR5(-) CD4(+) cells compared to HC. Both LT patients exhibited a rise in IgA(+) memory B cells and plasmablasts compared to HC and FA. CONCLUSIONS: LT has an impact on humoral immunity, remarkably in those patients developing FA. The increase in serum markers of mucosal IgA, food allergen-specific IgA and cTfh cells observed in LTFA, point towards a disturbance in intestinal immune homoeostasis in this patient group.
Subject(s)
Food Hypersensitivity/blood , Food Hypersensitivity/immunology , Immunoglobulin A/immunology , Liver Transplantation , T-Lymphocytes, Helper-Inducer/immunology , Adolescent , Age Factors , B-Lymphocyte Subsets/immunology , B-Lymphocyte Subsets/metabolism , Biomarkers , CD4 Lymphocyte Count , Child , Child, Preschool , Female , Food Hypersensitivity/diagnosis , Humans , Immunoglobulin A/blood , Immunoglobulin A, Secretory/immunology , Immunoglobulin E/blood , Immunoglobulin E/immunology , Immunologic Memory , Immunophenotyping , Infant , Liver Transplantation/adverse effects , Male , T-Lymphocytes, Helper-Inducer/metabolismABSTRACT
BACKGROUND: Infection with influenza virus has been associated with seemingly opposing effects on the development of asthma. However, there are no data about the effects of mucosal vaccination with inactivated influenza on the inception of allergic asthma. OBJECTIVE: To assess the immunological effects of inhaled inactivated influenza vaccine, using two different types of flu vaccines, on the inception of allergic sensitization and allergen-mediated airway disease in a mouse model. METHODS: BALB/c mice were intranasally or intratracheally vaccinated with whole or split influenza virus vaccine (days -1 or -1, 27) before systemic sensitization with ovalbumin (OVA) (days 1, 14) and repeated airway allergen challenges (days 28-30). Allergen sensitization (IgE serum levels), airway inflammation (differential cells in bronchoalveolar lavage fluid) and airway hyper-reactivity (AHR) (in vivo lung function) were analysed. RESULTS: The intranasal instillation of whole influenza vaccine before allergen sensitization significantly reduced the serum levels of total and OVA-specific IgE as well as allergen-induced AHR. Prevention was due to an allergen-specific shift from a predominant T helper (Th)2- towards a Th1-immune response. Application of split influenza vaccine did not show the same preventive effect. CONCLUSION: Intranasal administration of inactivated whole influenza vaccine reduced subsequent allergen sensitization and prevented allergen-induced AHR. Our results show that the composition of the influenza vaccine has a major influence on subsequent development of allergen-induced sensitization and AHR, and suggest that mucosal inactivated whole influenza vaccination may represent a step towards the development of a preventive strategy for atopic asthma.
Subject(s)
Asthma/prevention & control , Bronchial Hyperreactivity/prevention & control , Influenza A virus/immunology , Influenza Vaccines/immunology , Th1 Cells/immunology , Th2 Cells/immunology , Vaccines, Inactivated/immunology , Administration, Intranasal , Allergens/immunology , Allergens/toxicity , Animals , Asthma/chemically induced , Asthma/immunology , Bronchial Hyperreactivity/chemically induced , Bronchial Hyperreactivity/immunology , Bronchoalveolar Lavage Fluid/immunology , Female , Influenza Vaccines/administration & dosage , Mice , Mice, Inbred BALB C , Ovalbumin/immunology , Ovalbumin/toxicity , Vaccines, Inactivated/administration & dosageABSTRACT
A study was made in Belgium in order to assess the completeness and specificity of the recording of meningococcal disease by routine sources of information. Ninety-three cases identified in a hospital survey were linked with those recorded in mortality statistics, in the notification of communicable diseases, and by the National Reference Laboratory for meningococci. Statistics based on mortality data appeared to be of low validity. The overall completeness of recording was 44% for the notification of communicable disease, and 40% for the reference laboratory. When these two sources were used for surveillance, the completeness of case-finding increased to 56%. When the analysis was restricted to bacteriologically-confirmed cases, the completeness of recording was 62% for the notification system, 70% for the laboratory, and 84% for both sources. The surveillance of communicable diseases should rely on various sources of information. Laboratory data should be systematically used in order to improve both the completeness of recording and the specificity of case-ascertainment.