title: Coxsackievirus B4 infection of murine foetal thymus organ cultures.
abstract: The infection of foetal thymus with coxsackievirus B4 (CV-B4) E2 has been studied ex vivo by using CD-1 mice on foetal day 14, as a ready source of organs for experimentation to investigate the hypothesis of the role of thymic viral infections in the pathogenesis of type 1 diabetes. The replication of CV-B4 E2 in murine foetal thymus organ cultures has been demonstrated by evaluating the levels of positive- and negative-stranded viral RNA in cells by using a real-time quantitative RT-PCR method and by determining titres of infectious viral particles in culture supernatants for 7 days post-infection (p.i.). Staining of tissue sections with an anti-cytokeratin antibody and haematoxylin-eosin showed that CV-B4 infection had no visible effect on cell survival and organ integrity. Cell counts in mock- and virus-infected foetal thymus organ cultures increased from day 1 through day 7, and live cell numbers were comparable in both conditions as shown by Trypan blue exclusion test and 7-amino-actinomycin D staining of thymocytes. Compared with controls on day 7 p.i., cytofluorometric analyses on cells from CV-B4 E2-infected foetal thymus organ cultures displayed a marked increase in the percentage of the most immature CD3(-)CD4(-)CD8(-) thymocytes, and a decrease in the percentage of immature CD3(-)CD4(+)CD8(+) cells, together with an increase in the percentage of mature CD3(+)CD4(+) and CD3(+)CD8(+) cells. These data show that CV-B4 E2 disturbs T-cell maturation and differentiation processes in infected murine foetal thymus organ cultures and provide evidence of a suitable system to investigate the effect of viruses in T-cell differentiation.
authors.affiliation: Centre d'Immunologie de Liège (CIL), Institut de Pathologie 4, Université de Liège, Liège (Sart-Tilman), Belgium.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Brilot
authors.forename: Hela
authors.initials: H
authors.lastname: Jaïdane
authors.forename: Vincent
authors.initials: V
authors.lastname: Geenen
authors.forename: Didier
authors.initials: D
authors.lastname: Hober
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D002452:Cell Count; D002454:Cell Differentiation; D002470:Cell Survival; D003609:Dactinomycin / Q000031:analogs & derivatives / Q000378:metabolism; D029822:Enterovirus B, Human / Q000302:isolation & purification; D004769:Enterovirus Infections / Q000821:virology*; D005434:Flow Cytometry; D051379:Mice; D009924:Organ Culture Techniques; D012367:RNA, Viral / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000737:chemistry / Q000166:cytology; D013950:Thymus Gland / Q000473:pathology / Q000821:virology*; D013997:Time Factors; D014343:Trypan Blue / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D012367:RNA, Viral; D003609:Dactinomycin; C025942:7-aminoactinomycin D; D014343:Trypan Blue