o:30738 Age and gender associated changes in immunoglobulin subclass levels specific to S.pneumoniae, serotype 1 Promene u nivoima imunoglobulinskih podklasa specifičnih za S. pneumoniae, serotip 1, u vezi sa godinama i polom en ABSTRACT S. pneumoniae is an important human pathogen which has a polysaccharide capsule with virulent properties. This work aims to estimate the titres of S. pneumoniae specific IgG and IgA isotypes, with respect to age and sex. An in-house whole bacterial cell ELISA was used for the determination of relative levels and endpoint titres of IgG subclasses and IgA1 subclass specific for S. pneumoniae serogroup 1, and to quantify specific IgG1 and IgG2 levels. Significantly lower anti-pneumococcus IgG1 titres were found in older individuals, which was more pronounced in men. Lower IgG2 titres were detected in men over 50 years of age, in comparison to women under 50 years of age. The levels of IgG3 and IgG4 did not differ between different sex and age groups. Lower IgA1 levels were detected in male individuals in both age groups in comparison to females under 50 years of age. The levels of IgG1 showed a moderate correlation with IgG4 in younger individuals of both sexes (r = 0.61 in men and 0.63 in women) which was not noted in the older age group. We highlight the deficiency in humoral immunity in older people, especially male and suggest immunization of this population with pneumococcal vaccines. Ageing; Anti-bacterial antibodies; Anti-pneumococcus antibodies; Sex characteristics 1552099 10.1016/j.cimid.2022.101834 2023-09-07T06:29:54.500Z 44 yes 46 Sanja Knežević Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia Dejana Kosanović Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia person Luka Dragačević Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia person Irena Živković Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia person Vesna Ilić Institute for Medical Research, National Institute of Republic of Serbia, University of Belgrade, Serbia person Ljiljana Hajduković University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor biohemijskih nauka person 0000-0003-0720-2345 Olivera Savić Institute for Blood Transfusion of Serbia, Belgrade, Serbia person Rajna Minić Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia person application/pdf 9037 https://phaidrabg.bg.ac.rs/o:30738 no yes 1 70 92000001 11A25 11A29 11A2903 Comparative Immunology, Microbiology and Infectious Diseases 87 Elsevier 2022