Análise in silico de fatores de virulência de Chlamydia psittaci com potencial aplicação no desenvolvimento de vacinas e estudo do MHC de psitacídeos endêmicos do Brasil

Abstract

Chlamydia psittaci is an obligate intracellular pathogen of major zoonotic importance, widely associated with avians of the group Psittaciformes, with the potential to cause avian chlamydiosis and psittacosis in humans. The close relationship between these hosts and the infectious agent represents both a sanitary and conservation concern. The study of the Major Histocompatibility Complex (MHC) in psittacine species can serve as an important model for investigating host-pathogen interactions and the adaptive immune response of these avians, contributing to the development of strategies for the conservation of the group. This study aimed to investigate in silico the MHC of psittacine species endemic to Brazil and to perform the prediction of virulence factors and potential vaccine targets against C. psittaci. In the first chapter, 39 MHC class II sequences from Forpus passerinus and Amazona aestiva were identified and analyzed, with phylogenetic analyses indicating functional relationships with mammalian DRB and avian BL loci. Epitope prediction of the MOMP protein revealed regions with high binding affinity to MHC II molecules, including one shared between avians and mammals, suggesting potential for the development of broad-spectrum immunogens. In the second chapter, the complete proteome of a C. psittaci strain was analyzed for the identification of proteins associated with virulence, subcellular localization, and protein-protein interactions (PPI), highlighting molecular targets relevant to understanding pathogenesis and vaccine design. The results reinforce the applicability of in silico approaches in the immunogenetics of non-model species and in the search for new strategies for the prevention and control of avian chlamydiosis.