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Characterization of avian ?? T-cell subsets after Salmonella enterica serovar Typhimurium infection of chicks.

ABSTRACT: Avian ?? T lymphocytes are frequently found in blood and organs and are assumed to be crucial to the immune defense against Salmonella infections of chicks. To elucidate the so-far-unknown immunological features of subpopulations of avian ?? T cells in the course of infection, day-old chicks were infected orally with Salmonella enterica serovar Typhimurium. Until 11 days after infection, the occurrence as well as transcription of the CD8 antigen and immunologically relevant protein genes of CD8?(-) and CD8?(+high) (CD8??(+) CD8??(+)) ?? cells were analyzed using flow cytometry and quantitative real-time reverse transcription-PCR (RT-PCR) with blood, spleen, thymus, and cecum samples. After infection, an increased percentage of CD8?(+high) ?? T lymphocytes was found in blood, in spleen, and, with the highest values and most rapidly, in cecum. Within the CD8?(+high) subset, a significant rise in the number of CD8??(+) cells was accompanied by enhanced CD8? antigen expression and reduced gene transcription of the CD8? chain. CD8??(+) and CD8??(+) cells showed elevated transcription for Fas, Fas ligand (FasL), interleukin-2 receptor ? (IL-2R?), and gamma interferon (IFN-?). While the highest fold changes in mRNA levels were observed in CD8??(+) cells, the mRNA expression rates of CD8??(+) cells never significantly exceeded those of the CD8??(+) cells. In conclusion, both CD8?(+high) ?? T-cell subpopulations (CD8??(+) and CD8??(+)) might be a potential source of IFN-? in Salmonella-infected chicks. However, due to their prominent frequency in blood and organs after infection, the avian CD8??(+) ?? T-cell subset seems to be unique and of importance in the course of Salmonella Typhimurium infection of very young chicks.

SUBMITTER: Pieper J

PROVIDER: S-EPMC3028855 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Characterization of avian γδ T-cell subsets after Salmonella enterica serovar Typhimurium infection of chicks.

Pieper Jana J Methner Ulrich U Berndt Angela A

Infection and immunity 20101115 2

Avian γδ T lymphocytes are frequently found in blood and organs and are assumed to be crucial to the immune defense against Salmonella infections of chicks. To elucidate the so-far-unknown immunological features of subpopulations of avian γδ T cells in the course of infection, day-old chicks were infected orally with Salmonella enterica serovar Typhimurium. Until 11 days after infection, the occurrence as well as transcription of the CD8 antigen and immunologically relevant protein genes of CD8α ...[more]

PMID: 21078853

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Dataset Information

Characterization of avian ?? T-cell subsets after Salmonella enterica serovar Typhimurium infection of chicks.

Publications

Characterization of avian γδ T-cell subsets after Salmonella enterica serovar Typhimurium infection of chicks.

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