Typhoid fever as cellular microbiological model

• Published in: Revista do Instituto de Medicina Tropical de São Paulo Vol. 45; no. 4; pp. 185 - 191
• Main Authors: Andrade, Dahir Ramos de, Andrade Júnior, Dahir Ramos de
• Format: Journal Article
• Language: English
• Published: Brazil Instituto de Medicina Tropical de Sao Paulo 01.07.2003; Instituto de Medicina Tropical; Universidade de São Paulo (USP)
• Subjects: Bacteria-Cell interaction; Bacterial Adhesion - immunology; Bacterial Adhesion - physiology; Bacterial Proteins - genetics; Cellular Microbiology; Humans; Immunity, Cellular - immunology; Lipopolysaccharides - immunology; Membrane Glycoproteins - immunology; Models, Biological; Receptors, Cell Surface - immunology; Salmonella enterica serovar Typhi; Salmonella typhi - genetics; Salmonella typhi - immunology; Salmonella typhi - pathogenicity; Toll-Like Receptors; TROPICAL MEDICINE; Typhoid Fever; Typhoid Fever - etiology; Typhoid Fever - immunology; Typhoid Fever - microbiology; Virulence - genetics; Virulence - immunology; Salmonella enterica serovar Typhi; Cellular Microbiology; Bacteria-Cell interaction; Typhoid Fever
• ISSN: 0036-4665; 1678-9946; 0036-4665; 1678-9946
• DOI: 10.1590/S0036-46652003000400002

The knowledge about typhoid fever pathogenesis is growing in the last years, mainly about the cellular and molecular phenomena that are responsible by clinical manifestations of this disease. In this article are discussed several recent discoveries, as follows: a) Bacterial type III protein secretion system; b) The five virulence genes of Salmonella spp. that encoding Sips (Salmonella invasion protein) A, B, C, D and E, which are capable of induce apoptosis in macrophages; c) The function of Toll R2 and Toll R4 receptors present in the macrophage surface (discovered in the Drosophila). The Toll family receptors are critical in the signalizing mediated by LPS in macrophages in association with LBP and CD14; d) The lines of immune defense between intestinal lumen and internal organs; e) The fundamental role of the endothelial cells in the inflammatory deviation from bloodstream into infected tissues by bacteria. In addition to above subjects, the authors comment the correlation between the clinical features of typhoid fever and the cellular and molecular phenomena of this disease, as well as the therapeutic consequences of this knowledge. O conhecimento sobre a patogênese da febre tifóide vem crescendo nos últimos anos, principalmente sobre os fenômenos celulares e moleculares, responsáveis pelas manifestações clínicas desta doença. Neste artigo são discutidas várias descobertas recentes, a saber: a) O sistema bacteriano de secreção protéica tipo III; b) Os cinco genes de virulência da Salmonella spp. que codificam os Sips (Salmonella invasion protein) A, B, C, D e E, capazes de induzir apoptosis em macrófagos; c) A função dos receptores Toll R2 e Toll R4 presentes na superfície de macrófagos (descobertos na Drosophila). Os receptores da família Toll são críticos na sinalização mediada por LPS nos macrófagos, em associação com LBP e CD14; d) As linhas de defesa imune entre o lúmen intestinal e os órgãos internos; e) O papel fundamental das células endoteliais no desvio inflamatório, da corrente sanguínea para os tecidos infectados pela bactéria. Além destes aspectos, os autores comentam a correlação entre as características clínicas da febre tifóide e os fenômenos celulares e moleculares da doença, bem como as conseqüências terapêuticas deste conhecimento.