Molecular, Cellular and Functional Analysis of TRγ Chain Along the European Sea Bass Dicentrarchus labrax Development

International Journal of Molecular Sciences

Andrea Miccoli¹  Simona Picchietti¹  AnnaMaria Fausto¹  Francesco Buonocore¹  Valeria Pianese¹  Giuseppe Scapigliati¹  Laura Guerra¹  PaoloRoberto Saraceni¹  TaniaDe Wolf²  Ana Couto³  AnnaRita Taddei⁴ 

[1] Department for Innovation in Biological, Agro-Food and Forest Systems, University of Tuscia, Largo dell’Università, 01100 Viterbo, Italy;INVE Aquaculture Research Center, 57016 Rosignano Solvay, Italy;Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Av. General Norton de Matos, 4450-208 Matosinhos, Portugal;Section of Electron Microscopy, Great Equipment Center, University of Tuscia, 01100 Viterbo, Italy;

关键词: T cell receptor chain gamma;    immune system;    ontogeny;    intestine;    nutritional immunity;   

DOI  :  10.3390/ijms22073376

来源: DOAJ

【 摘 要 】

In jawed vertebrates, adaptive immune responses are enabled by T cells. Two lineages were characterized based on their T cell receptor (TcR) heterodimers, namely αβ or γδ peptide chains, which display an Ig domain-type sequence that is somatically rearranged. γδ T cells have been less extensively characterized than αβ and teleost fish, in particular, suffer from a severe scarcity of data. In this paper, we worked on the well-known model, the European sea bass Dicentrarchus labrax, to broaden the understanding of teleost γδ-T cells. The T cell receptor chain (TR) γ transcript was expressed at a later developmental stage than TRβ, suggesting a layered appearance of fish immune cells, and the thymus displayed statistically-significant higher mRNA levels than any other organ or lymphoid tissue investigated. The polyclonal antibody developed against the TRγ allowed the localization of TRγ-expressing cells in lymphoid organs along the ontogeny. Cell positivity was investigated through flow cytometry and the highest percentage was found in peripheral blood leukocytes, followed by thymus, gut, gills, spleen and head kidney. Numerous TRγ-expressing cells were localized in the gut mucosa, and the immunogold labelling revealed ultrastructural features that are typical of T cells. At last, microalgae-based diet formulations significantly modulated the abundance of TRγ⁺ cells in the posterior intestine, hinting at a putative involvement in nutritional immunity. From a comparative immunological perspective, our results contribute to the comprehension of the diversity and functionalities of γδ T cells during the development of a commercially relevant marine teleost model.

【 授权许可】

Unknown