Characterisation and expression analysis of the Atlantic halibut (Hippoglossus hippoglossus L.) cytokines: IL-1β, IL-6, IL-11, IL-12β and IFNγ

Genes encoding the five Atlantic halibut (Hippoglossus hippoglossus L.) cytokines; interleukin (IL)-1β, IL-6, IL-11b, IL-12βc, and interferon (IFN) γ, were cloned and characterised at a molecular level. The genomic organisation of the halibut cytokine genes was similar to that seen in mammals and/or other fish species. Several mRNA instability motifs were found within the 3′-untranslated region (UTR) of all cytokine cDNA sequences. The putative cytokine protein sequences showed a low sequence identity with the corresponding homologues in mammals, avian and other fish species. Nevertheless, important structural features were presumably conserved such as the presence, or absence in the case of IL-1β, of a signal peptide, secondary structure and family signature motifs. The relative expression pattern of the cytokine genes was analyzed in several halibut organs, revealing a constitutive expression in both lymphoid and non-lymphoid organs. Interestingly, the gills showed a relatively high expression of IL-1β, IL-12βc and IFNγ. The real time RT-PCR data also showed that the mRNA level of IL-1β, IL-6, IL-12βc and IFNγ was high in the thymus, while IL-11b was relatively highly expressed in the posterior kidney and posterior gut. Moreover, the halibut brain showed a relatively high level of IL-6 transcripts. Anterior kidney leucocytes in vitro stimulated with imiquimod showed a significant increase in mRNA level of the five halibut cytokine genes. The sequence and characterisation data presented here will be useful for further investigation of both innate and adaptive immune responses in halibut, and be helpful in the design of vaccines for the control of various infectious diseases

Importância do camundongo mdx na fisiopatologia da distrofia muscular de Duchenne The importance of mdx mouse in the pathophysiology of Duchenne's muscular distrophy

O camundongo mdx desenvolve distrofia muscular recessiva ligada ao cromossoma X (locus Xp21.1) e não expressa distrofina. Embora não apresente intensa fibrose do tecido muscular e acúmulo de tecido adiposo, é considerado o modelo animal mais adequado da distrofia muscular de Duchenne. As alterações estruturais no tecido muscular associadas à mionecrose e presença do infiltrado inflamatório com predomínio de linfócitos e monócitos/macrófagos sugerem uma participação do sistema imunológico nesta miopatia. Além disso a modulação na expressão dos componentes da matriz extracelular no microambiente muscular nas várias fases da doença (início, mionecrose, regeneração) indicam um papel importante do conjuntivo no direcionamento das células inflamatórias para o foco da lesão muscular. O camundongo mdx coloca-se como um excelente modelo para o estudo dos mecanismos patogenéticos da mionecrose e regeneração na distrofia muscular de Duchenne, possibilitando inclusive o desenvolvimento de estratégias terapêuticas mais adequadas.<br>The mdx mouse develop an X-linked recessive muscular dystrophy (locus Xp21.1) and lack dystrophin expression. Despite showing less intense myofibrosis and scarce deposition of fatty tissue, mdx mice are considered an adequate animal model for studies on the pathogenesis of Duchenne-type muscular dystrophy. Marked histological alterations in the muscular tissues associated to myonecrosis and inflammatory mononuclear cell infiltrate (lymphocytes, monocytes/macrophages) suggest a participation of the immune system in this myopathy. Modulation of the extracellular matrix (ECM) components in the muscular tissue during all phases (onset, myonecrosis and regeneration) of disease, indicate an important role for the ECM driving inflammatory cells to the foci of lesion. Therefore mdx mice should be regarded as an important tool for studies on pathogenetic mechanisms of Duchenne-type muscular dystrophy. Such experimental model would allow development of new therapeutic approaches for increasing survival and clinical amelioration