Degen WGJ, Daal NV, Rothwell L, Kaiser P, Schijns VEJC. Th1/Th2 polarization by viral and helminth infection in birds.
Vet Microbiol 2005;
105:163-7. [PMID:
15708812 DOI:
10.1016/j.vetmic.2004.12.001]
[Citation(s) in RCA: 124] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2004] [Revised: 11/18/2004] [Accepted: 12/01/2004] [Indexed: 02/02/2023]
Abstract
Mammals developed an immune system able to functionally polarize into so-called type 1 or type 2 immune pathways, to resolve infections with intracellular and extracellular pathogens, respectively. In the well-studied avian immune system of the chicken, however, no evidence for polarized immunity could be found, as yet. To investigate whether these two major arms of mammalian immunity, regulated by a T helper (Th)1/Th2 cytokine balance, evolved similarly in birds, chickens were exposed to a prevalent intracellular (viral) or extracellular (helminth) infection. By using semi-quantitative RT-PCR analysis we provide evidence that polarization of Th1/Th2 type immunity extends beyond mammalian species, and, therefore, has been evolutionary conserved for more than 300 million years, when the lineages of mammalian and avian vertebrates are assumed to have segregated.
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