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The molecular characteristics of Yersinia ruckeri such as total proteins (TP), outer membrane proteins OMP) and lipopolysaccharides (LPS) in 34 isolates from rainbow trout farms in Tehran, Mazandaran and Zanjan provinces were determined, using SDS-PAGE method. The molecular weight (MW) for TP of all bacterial isolates was mostly less than 100 KD with a banding density in range 28 to 100 KD. Also, protein pattern of OMP consisted of three major bands with MW of 28-35 KD (two bands) and 10-17 KD (one band) plus some minor bands with MW of 48-75 KD and 17-28 KD. In addition, the LPS pattern of all bacterial isolates were less than 130 KD with the most band density in range 28-100 KD. These results show that the banding profile of TP, OMP and LPS of all isolates of Y. ruckeri were identical, demonstrating minimum heterogeneity among Iranian isolates of Y. ruckeri. Therefore, it is feasible for the formulation of a monovalent vaccine to yersiniosis in future.

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Objective: Astrocytes are the most abundant glial cell type. They may promote or inhibit CNS inflammation depending on which cytokines are secreted. Astrocytes also have immune roles. IL-19, IL-20, and IL-24 activate a heterodimer receptor composed of the IL-20R1 α-chain and the IL-20R2 β-chain. It has long been considered that signaling by these receptor complexes affects immunological reactions, however the biological functions of IL-20R1 and IL-20R2 in the brain remain unclear. As the first step to address the role of these cytokine receptors in the brain, in this study we have researched the expressions of IL-20R1 and IL-20R2 in C57BL/6 mice astrocytes. Methods: We examined expressions of IL-20R1 and IL-20R2 proteins in mice astroglial cells and in the 1321N1 astrocytoma cell line in response to MOG, LPS and GM-CSF by flow cytometry. The effect of LPS on mRNA expression of IL-20R1 and IL-20R2 was investigated by RT-PCR. Results: We provide, for the first time, evidence that astrocytes expressed IL-20R1 and IL-20R2 mRNA not only in response to LPS stimulation but also in unstimulated astrocytes. We did not observe the expressions of IL-20R1 and IL-20R2 proteins in mice astroglial cells and the 1321N1 astrocytoma cell line. Conclusions: IL-20R1 and IL-20R2 mRNA are constitutively expressed in astrocytes. Because the majority of neuropathological processes involve astrocytes and inflammatory cytokines, the results of this study, which are reported for the first time, have important implications for future research.