Infectious and immunologic phenotype of MECP2 duplication syndrome.

Abstract

MECP2 (methyl CpG binding protein 2) duplication causes syndromic intellectual disability. Patients often suffer from life-threatening infections, suggesting an additional immunodeficiency. We describe for the first time the detailed infectious and immunological phenotype of MECP2 duplication syndrome. 17/27 analyzed patients suffered from pneumonia, 5/27 from at least one episode of sepsis. Encapsulated bacteria (S.pneumoniae, H.influenzae) were frequently isolated. T-cell immunity showed no gross abnormalities in 14/14 patients and IFNy-secretion upon ConA-stimulation was not decreased in 6/7 patients. In 6/21 patients IgG2-deficiency was detected - in 4/21 patients accompanied by IgA-deficiency, 10/21 patients showed low antibody titers against pneumococci. Supra-normal IgG1-levels were detected in 11/21 patients and supra-normal IgG3-levels were seen in 8/21 patients - in 6 of the patients as combined elevation of IgG1 and IgG3. Three of the four patients with IgA/IgG2-deficiency developed multiple severe infections. Upon infections pronounced acute-phase responses were common: 7/10 patients showed CRP values above 200 mg/l. Our data for the first time show systematically that increased susceptibility to infections in MECP2 duplication syndrome is associated with IgA/IgG2-deficiency, low antibody titers against pneumococci and elevated acute-phase responses. So patients with MECP2 duplication syndrome and low IgA/IgG2 may benefit from prophylactic substitution of sIgA and IgG.

• Authors: Michael Bauer, Uwe Kölsch, Renate Krüger, Nadine Unterwalder, Karin Hameister, Fabian Marc Kaiser, Aglaia Vignoli, Rainer Rossi, Maria Pilar Botella, Magdalena Budisteanu, Monica Rosello, Carmen Orellana, Maria Isabel Tejada, Sorina Mihaela Papuc, Oliver Patat, Sophie Julia, Renaud Touraine, Thusari Gomes, Kirsten Wenner, Xiu Xu, Alexandra Afenjar, Annick Toutain, Nicole Philip, Aleksandra Jezela-Stanek, Ludwig Gortner, Francisco Martinez, Bernard Echenne, Volker Wahn, Christian Meisel, Dagmar Wieczorek, Salima El-Chehadeh, Hilde Van Esch, Horst von Bernuth
• Journal: Journal of clinical immunology (J Clin Immunol) Vol. 35 Issue 2 Pg. 168-81 (Feb 2015) ISSN: 1573-2592 [Electronic] Netherlands
• PMID: 25721700 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Acute-Phase Proteins
• Immunoglobulins
• Methyl-CpG-Binding Protein 2
• C-Reactive Protein

Topics

• Acute-Phase Proteins (metabolism)
• Adolescent
• Adult
• C-Reactive Protein (metabolism)
• Child
• Child, Preschool
• Cohort Studies
• Female
• Gene Duplication
• Genotype
• Humans
• Immunity, Cellular
• Immunity, Humoral
• Immunoglobulins (blood, immunology)
• Infections (diagnosis, drug therapy, etiology)
• Male
• Mental Retardation, X-Linked (complications, diagnosis, immunology)
• Methyl-CpG-Binding Protein 2 (genetics)
• Middle Aged
• Phenotype
• Young Adult