Hematologic values of captive Acadian redfish (Sebastes fasciatus).

The Acadian redfish (Sebastes fasciatus) is a popular display animal in public aquaria and an important fisheries resource, but hematologic values for this species have not been reported. This study investigated hematocrit, leucocyte counts, and leucocyte differential counts for 29 captive Acadian redfish collected in 2006 and 2008. All fish were judged to be in good health based on behavior, appetite, physical examination, skin cytology, and gill biopsy. Fish were anesthetized with tricaine methanesulfonate (MS-222) for blood collection from the ventral coccygeal vasculature. In 2008, MS-222 was buffered with sodium bicarbonate. Hematocrit values ranged from 27% to 45% (mean = 33% in 2006, mean = 31% in 2008). Leucocyte counts ranged from 670 to 35,000 cells/microl (mean = 6430 cells/microl in 2006, and 13,130 cells/microl in 2008). Lymphocytes were the most numerous of the leucocytes, followed by neutrophils and monocytes. Eosinophils and basophils were not seen. Fish weights were significantly greater in 2006, whereas total leucocyte counts, lymphocyte counts, and monocyte counts were significantly greater in 2008. Differences in leucogram values between the two groups may have been due to differences in size, age, anesthetic method, or other undetected factors. This is the first report of leucogram values for a species of the family Scorpaenidae. In general, values were similar to those of other teleosts, in which leucocyte counts can be quite variable.

Identification of a regulatory autophosphorylation site in the serine-threonine kinase RIP2.

Receptor-interacting protein 2 (RIP2) is a serine-threonine kinase that mediates signaling for many receptors of the innate and adaptive immune systems. Toll like receptors (TLR) are an important component of the innate immune response. Stimulation of RIP2-deficient cells with ligands for TLR 2, 3 and 4 results in impaired cytokine production and decreased activation of NF-kB and MAP kinases compared to wild-type cells. Stimulation of TLR 4 with its ligand lipopolysaccaride (LPS) leads to the activation of RIP2 kinase activity and its autophosphorylation. Here we identify serine residue 176 as a site of autophosphorylation using a combination of mass spectrometry and mutational analysis. Mutation of S176 to alanine not only abolishes autophosphorylation of RIP2 but also significantly decreases its catalytic activity. A phospho-specific anti-S176 antibody detects wild-type RIP2 but not kinase-dead RIP2 or the RIP2 S176A mutant. Endogenous RIP2 in THP-1 cells and mouse bone marrow derived macrophages can be detected by the phospho-RIP2 (S176) antibody only after stimulation with LPS suggesting that the antibody recognizes activated RIP2. In summary, our results indicate that S176 is a regulatory autophosphorylation site for RIP2 and that S176 phosphorylation can be used to monitor the activation state of RIP2.