title: Association between IgG subclasses against Toxoplasma gondii and clinical signs in newborns with congenital toxoplasmosis.
abstract: BACKGROUND
  The aim of this study was to evaluate the association between clinical signs of congenital toxoplasmosis and IgG subclasses found in newborns participating in the Minas Gerais State Neonatal Screening Program.
  
  
  METHODS
  Neonates with confirmed congenital toxoplasmosis underwent standardized ophthalmologic evaluation, neuroimaging studies and hearing assessment, as well as enzyme-linked immunosorbent assay testing for total IgG and its subclasses (IgG1, IgG2, IgG3 and IgG4) against soluble (STAg) and recombinant (rSAG1 and rMIC3) antigens of Toxoplasma gondii.
  
  
  RESULTS
  Newborns with congenital toxoplasmosis but without ocular lesions were more likely to present anti-rMIC3 total IgG when compared with those newborns with active or cicatricial retinochoroidal lesions. Detection of anti-rMIC3 IgG2 and IgG4 was associated with presence of retinochoroidal lesions and intracranial calcifications, with higher mean reactivity index values than unaffected newborns with congenital toxoplasmosis. Anti-STAg IgG3 was associated with newborns without neurologic damage.
  
  
  CONCLUSIONS
  Specific subclasses of IgG antibodies reacting with recombinant antigens of T. gondii may serve as biomarkers of neurologic and ocular changes in newborns with congenital toxoplasmosis.
authors.affiliation: Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Carlos Henryque
authors.initials: CH
authors.lastname: de Souza-e-Silva
authors.forename: Daniel Vitor
authors.initials: DV
authors.lastname: Vasconcelos-Santos
authors.forename: Gláucia Queiroz
authors.initials: GQ
authors.lastname: de Andrade
authors.forename: Ericka Viana Machado
authors.initials: EV
authors.lastname: Carellos
authors.forename: Roberta Maia
authors.initials: RM
authors.lastname: de Castro Romanelli
authors.forename: Luciana Macedo
authors.initials: LM
authors.lastname: de Resende
authors.forename: José Nélio
authors.initials: JN
authors.lastname: Januário
authors.forename: Mariangela
authors.initials: M
authors.lastname: Carneiro
authors.forename: Ana Carolina
authors.initials: AC
authors.lastname: de Aguiar Vasconcelos Carneiro
authors.forename: Ricardo Wagner
authors.initials: RW
authors.lastname: de Almeida Vitor
mesh_terms: D000913:Antibodies, Protozoan / Q000097:blood / Q000145:classification* / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology; D015415:Biomarkers / Q000097:blood; D001938:Brazil / Q000453:epidemiology; D016009:Chi-Square Distribution; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000145:classification* / Q000276:immunology; D007223:Infant; D007231:Infant, Newborn; D014122:Toxoplasma / Q000276:immunology*; D014125:Toxoplasmosis, Congenital / Q000097:blood / Q000453:epidemiology / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D015415:Biomarkers; D007074:Immunoglobulin G