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A cDNA clone encoding a 380 a-a type 1 transmembrane protein with homology to human Siglec-3/CD33 was obtained from a swine small intestine library. An analysis of protein sequence identified two immunoglobulin-like domains, a transmembrane region, and a carboxi-terminal tail with two tyrosine-based signalling motifs. Binding assays of Siglec-3 transfected CHO cells to polyacrylamide glycoconjugates showed a preference for α2–6-linked sialic acids. Using mAbs raised against a fragment containing the two Ig-like domains, porcine Siglec-3 was found to be expressed on monocytes and granulocytes, and their bone marrow precursors. It was also detected in lymph node, splenic and alveolar macrophages. MAbs immunoprecipitated, from granulocyte lysates, a protein of 51–60 kDa under both non-reducing and reducing conditions. MAbs were also used to analyse functional activity of Siglec-3 on bone marrow and blood cells. Engagement of Siglec-3 by mAb had no apparent effect on cell proliferation or cytokine production. [ABSTRACT FROM AUTHOR]

Siglecs are sialic acid binding Ig-like proteins involved in the control of leukocyte responses. In this study we describe the characterization of a porcine orthologue of Siglec-10. A cDNA clone was obtained from a porcine library which encodes a protein with sequence homology to human Siglec-10. This cDNA codes for a type I transmembrane protein containing four Ig-like domains, a transmembrane region, and a cytoplasmic tail with three tyrosine-based motifs, including a membrane-proximal Grb2-binding motif, and two ITIM motifs. When expressed on transfected cells, porcine Siglec-10 was able to bind red blood cells in a sialic acid-dependent manner. Monoclonal antibodies were developed against this protein and used to examine its cell and tissue distribution in the pig. Siglec-10 was found to be expressed on blood B cells and B cell areas of the spleen and lymph nodes. A weak expression was also detected on monocytes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Generation of cell lines expressing porcine Siglec-5. [•] Development of monoclonal antibodies to porcine Siglec-5. [•] Porcine Siglec-5 is expressed on myeloid cells and their precursors, and at low levels on plasmacytoid dendritic cells. [ABSTRACT FROM AUTHOR]

Abstract: A 58-year-old man underwent kidney transplantation on November 14, 2002 for end-stage kidney disease after Chinese herb nephropathy. Immunosuppressive therapy was maintained with tacrolimus, mycophenolate mofetil, and methylpredonisolone. He was diagnosed with right ureteral cancer and underwent right nephroureterectomy on December 13, 2003. Then, he underwent left nephroureterectomy for left ureteral cancer on March 5, 2004. Subsequently, he was diagnosed with multiple bladder cancers and carcinoma in situ. On August 31, he underwent radical cystectomy with an orthotopic ileal neobladder (Studer''s method). The postoperative course was uneventful. After 3 years follow-up, this patient shows no evidence of recurrence and his serum creatinine level is stable (1.7 mg/dL). The continence is maintained during both day and night; he voids without intermittent self-catheterization. We suggest that an orthotopic ileal neobladder is a safe method of urinary diversion after cystectomy in kidney transplant recipients. [Copyright &y& Elsevier]

CD200R1 and CD200R1-like are paired receptors which modulate activation of immune cells. Here, we describe the characterisation of their porcine homologues. Analysis of database porcine sequences shows an exceptionally high homology between the extracellular Ig-like domains of these receptors, being the rest more dissimilar. We have obtained two mAbs, PCT1 and PCT3, against a CD200R1-Fc recombinant protein, that bind on CHO cells expressing GFP-tagged CD200R1. The specificity of these mAbs was analysed on CD200R1 L, and also on a CD200R1 splicing variant that lacks the V-type Ig domain. PCT1 bound to both CD200R1 and CD200R1L, but not to the splicing variant, what suggests that recognises an epitope in the V-type Ig domain. PCT3 reacted with both CD200R1 variants, but not CD200R1L, probably binding to an epitope in the N-terminal sequence of CD200R1. Analysis of porcine cells with these mAbs showed expression of CD200R1/CD200R1L on B cells, monocytes and alveolar macrophages. • Porcine CD200R1 and CD200R1L show a single amino-acid difference in their Ig-like domains. • PCT1 and PCT3 mAbs discriminate between porcine CD200R1 and CD200R1L • PCT1 mAb binds both CD200R1 and CD200R1L while PCT3 mAb only reacts with CD200R1. • These mAbs stain monocytes, a subset of B lymphocytes and alveolar macrophages. [ABSTRACT FROM AUTHOR]