Aleksandra Szczawinska-Poplonyk1, Katarzyna Tapolska-Jozwiak2, Husam Samara3, Maciej Boruczkowski3, Barbara Wieckowska4. 1. Department of Pediatric Pneumonology, Allergology and Clinical Immunology, Poznan University of Medical Sciences, Poznan, Poland; ola@malwa.com.pl; aszczawinska@ump.edu.pl. 2. Department of Pediatric Pneumonology, Allergology and Clinical Immunology, Poznan University of Medical Sciences, Poznan, Poland. 3. Department of Immunology, Poznan University of Medical Sciences, Poznan, Poland. 4. Department of Computer Science, and Statistics, Poznan University of Medical Sciences, Poznan, Poland.
Abstract
BACKGROUND: Novel immunodiagnostic markers are required in order to discriminate between mild hypogammaglobulinemia and severe humoral primary immune deficiencies in children. The efficacy of an antibody response to infections and vaccines is underpinned by T follicular helper (Tfh) cells, activating an immunoglobulin class switch recombination, somatic hypermutations, and affinity maturation. OBJECTIVE: To determine the formation of the Tfh cells in antibody deficient children and to define their importance as prognostic markers helpful in defining the severity of hypogammaglobulinemia. METHODS: We retrospectively reviewed medical records of 200 children aged from 2 months to 10 years, in whom hypogammaglobulinemia was assessed, from January to December 2019. In all the children studied, a flow cytometric analysis of the Tfh cell compartment was performed. RESULTS: In young infants aged from 2 to 9 months, the mean relative frequency of the Tfh population was lower than in the control population. Concomitantly, the relative values of Tfh cells, corresponding with the 95th percentile, were below the reference values in all age groups. CONCLUSIONS: A deficiency of Tfh cells in young infants mirrors the immaturity of the humoral immune response, whereas in older children Tfh cells are proposed as a prognostic marker facilitating to distinguish between mild hypogammaglobulinemia and the developing common variable immunodeficiency.
BACKGROUND: Novel immunodiagnostic markers are required in order to discriminate between mild hypogammaglobulinemia and severe humoral primary immune deficiencies in children. The efficacy of an antibody response to infections and vaccines is underpinned by T follicular helper (Tfh) cells, activating an immunoglobulin class switch recombination, somatic hypermutations, and affinity maturation. OBJECTIVE: To determine the formation of the Tfh cells in antibody deficient children and to define their importance as prognostic markers helpful in defining the severity of hypogammaglobulinemia. METHODS: We retrospectively reviewed medical records of 200 children aged from 2 months to 10 years, in whom hypogammaglobulinemia was assessed, from January to December 2019. In all the children studied, a flow cytometric analysis of the Tfh cell compartment was performed. RESULTS: In young infants aged from 2 to 9 months, the mean relative frequency of the Tfh population was lower than in the control population. Concomitantly, the relative values of Tfh cells, corresponding with the 95th percentile, were below the reference values in all age groups. CONCLUSIONS: A deficiency of Tfh cells in young infants mirrors the immaturity of the humoral immune response, whereas in older children Tfh cells are proposed as a prognostic marker facilitating to distinguish between mild hypogammaglobulinemia and the developing common variable immunodeficiency.
Entities:
Keywords:
children; hypogammaglobulinemia follicular T helper cells; primary immunodeficiency
Authors: Aleksandra Szczawińska-Popłonyk; Katarzyna Ta Polska-Jóźwiak; Eyal Schwartzmann; Natalia Popłonyk Journal: Front Pediatr Date: 2022-03-23 Impact factor: 3.418