RESUMO
Rickettsia are obligate intracellular pathogens transmitted by arthropod vectors. The re-emergence of several rickettsioses imposes severe global health burden. In addition to the well-established rickettsial pathogens, newer rickettsial species and their pathogenic potentials are being uncovered. There are many reports of spotted and typhus fever caused by rickettsiae in India. Hence, in this study we screened the ectoparasites of pet and domestic animals for the presence of rickettsia using polymerase chain reaction. Nine cat flea samples (Ctenocephalides felis felis), that tested positive for the presence of rickettsia were subjected to Multi Locus Sequence Typing. Nucleotide sequencing and Phylogenetic analysis of gltA, ompB and 16rrs genes revealed that the rickettsiae detected in cat fleas was Rickettsia asembonensis. Further studies are required to assess Rickettsia asembonensis pathogenic potential to human and its enzootic maintenance of in various hosts and vectors.
Assuntos
Infecções por Rickettsia/transmissão , Rickettsia/genética , Sifonápteros/microbiologia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Bactérias/genética , Zoonoses Bacterianas/microbiologia , Zoonoses Bacterianas/transmissão , Ctenocephalides/microbiologia , DNA Bacteriano/genética , Índia/epidemiologia , Insetos Vetores/microbiologia , Tipagem de Sequências Multilocus/veterinária , Patologia Molecular , Filogenia , RNA Ribossômico 16S/genética , Rickettsia/isolamento & purificação , Infecções por Rickettsia/microbiologia , Infecções por Rickettsia/veterinária , Rickettsia felis/genéticaRESUMO
Rheumatoid arthritis (RA) is a polyarticular inflammatory, angiogenic disease. Synovial angiogenesis contributes to inflammation in RA. In this study we have developed an arthritic model in rats using a novel angiogenic protein (NAP), isolated from human synovial fluid of RA patients. We produced anti-NAP monoclonal antibodies (mAbs) and investigated the therapeutic efficacy of the same in adjuvant-induced or NAP-induced arthritis as a model of human RA. The treatment of arthritic rats with anti-NAP mAbs resulted in effective amelioration of paw oedema, radiological arthritic characteristics, serum levels of vascular endothelial growth factor (VEGF) and NAP, compared to that of untreated arthritic animals. Further, profiling of angiogenic markers such as synovial microvessel density, angiogenesis, CD31, VEGF and fms-like tyrosine kinase (Flt1) by immunohistochemistry both in arthritic and anti-NAP mAb-treated animals revealed the efficacy of mAb as an anti-angiogenic functional antibody. Therefore, NAP may be an attractive target to design anti-angiogenic and anti-arthritic therapies to control the pathogenesis of arthritis.