Enumeration of human peripheral blood lymphocytes secreting immunoglobulins of major classes and subclasses in healthy children and adults.
ABSTRACT The reverse enzyme-linked immunospot assay was modified to enumerate peripheral blood mononuclear cells (PBMC) secreting IgG1-4, IgA1-2, and IgM. Anti-human IgG F(ab')2 and mouse monoclonal antibodies specific to each of the isotypes were used as solid-phase capture antibodies and developing antibodies, respectively. Although attempts were also made to detect IgD- and IgE-secreting cells (SC), their numbers in the peripheral blood were too few to be reliably estimated. The assay was applied to study healthy subjects including 21 neonates within 3 days of birth, 44 1- to 48-month-old children, and 32 adults. Sixty percent of these neonates had IgM SC in small numbers (less than 20 per 10(6) PBMC), but only three neonates had IgSC of other isotypes. In contrast, by 1-2 months of age children had IgSC of all isotypes, including IgA2 and IgG4, often in higher numbers than adults. The relative frequencies of IgSC were IgA1 greater than IgG1 greater than IgM greater than IgG2 greater than IgG3 greater than IgG4 greater than IgA2 in the children and IgA1 greater than IgG1 greater than IgA2 greater than IgM greater than IgG4 greater than IgG2 greater than IgG3 in the adults. The order of the serum concentrations in the adults was IgG1 greater than IgG2 greater than IgA greater than IgM greater than IgG4 greater than IgG3. No correlation was found between the serum level and the IgSC number of individual isotypes (except for serum IgA and IgA1-SC). This new methodology should facilitate investigating the current status of immunoglobulin synthesis and the Ig repertoire in adults and children, in health and in disease.
- SourceAvailable from: Antonio Picarelli
Dataset: EMA-IgG1 JIM
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ABSTRACT: Background. The immunological bases for the efficacies of the two currently licensed influenza vaccines, the live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV), are not fully understood. The goal of this study was to identify specific B-cell responses correlated with the known efficacies of these two vaccines.Methods. We compared the B-cell and antibody responses after immunization with 2010/2011 IIV versus LAIV in young adults, focusing on peripheral plasmablasts at days 6-8 post-vaccination.Results. The quantities of vaccine-specific plasmablasts and plasmablast-derived polyclonal antibodies (PPAb) were significantly higher in IIV recipients than in LAIV recipients. No significant difference was detected in the avidity of vaccine-specific PPAb between the two vaccine groups. Proportionally, LAIV induced a greater vaccine-specific IgA plasmablast response as well as a greater plasmablast response to the conserved influenza nuclear protein than did IIV. The cross-reactive plasmablast response to heterovariant strains, as indicated by the relative levels of cross-reactive plasmablasts and the cross-reactive PPAb binding reactivity, was also greater in the LAIV group.Conclusions. Distinct quantitative and qualitative patterns of plasmablast responses were induced by LAIV and IIV in young adults; a proportionally greater cross-reactive response was induced by LAIV.The Journal of Infectious Diseases 03/2014; · 5.85 Impact Factor
- Immunology and Allergy Clinics of North America 05/1998; 18(2):401-419. · 2.38 Impact Factor