Galectin-8 in IgA Nephritis: Decreased Binding of IgA by Galectin-8 Affinity Chromatography and Associated Increased Binding in Non-IgA Serum Glycoproteins

Background Immunoglobulin A nephritis (IgAN) is the most common primary glomerulonephritis worldwide. It is caused by accumulation of IgA1-containing immune complexes in the kidney resulting in renal failure, which is thought to be due to altered glycosylation of IgA with a decrease of 2-3-sialylated galactosides (NeuAc alpha 2-3Gal). less thanbrgreater than less thanbrgreater thanPurpose The purpose of this study was to analyze whether altered glycosylation of IgA would lead to an altered binding to galectin-8, an endogenous lectin with strong affinity for 2-3-sialylated galactosides. Galectins are a family of beta-galactoside-binding proteins; by binding various glycoproteins, they play important roles in the regulation of cellular functions in inflammation and immunity. Hence, an altered binding of IgA to galectin-8 could lead to pathologic immune functions, such as glomerulonephritis. less thanbrgreater than less thanbrgreater thanMethods Affinity chromatography of serum glycoproteins on the human sialogalactoside-binding lectin galectin-8N permitted quantitation of bound and unbound fractions, including IgA. less thanbrgreater than less thanbrgreater thanResults Analysis of similar to 100 IgA nephritis sera showed that the galectin-8N unbound fraction of IgA increased compared to similar to 100 controls, consistent with the known loss of galactosylation. A subgroup of similar to 15% of the IgAN patients had a ratio of galectin-8 bound/unbound IgA andlt;0.09, not found for any of the controls. Unexpectedly, the galectin-8N-binding fraction of serum glycoproteins other than IgA increased in the sera of IgAN patients but not in controls, suggesting a previously unrecognized change in this disease. less thanbrgreater than less thanbrgreater thanConclusion This is the first study that relates a galectin, an endogenous lectin family, to IgA nephritis and thus should stimulate new avenues of research into the pathophysiology of the disease.Funding Agencies|Swedish Research Council (Vetenskapsradet)|2008-3356|Swedish Foundation for Swedish Research|FFL4|Swedish Healthcare System (ALF)||Region Skane||</p

Prognostic value of stage IV neuroblastoma metastatic immunophenotype in the bone marrow: preliminary report

AIM: To correlate the immunophenotype of metastatic cells in the bone marrow of patients with neuroblastoma with early treatment failure. METHODS: The studies were performed on bone marrow material obtained from children treated in the department of paediatric oncology, haematology, and transplantology, Poznan University of Medical Sciences, Poland from 1996 to 2003. Immunocytochemical analysis of nervous tissue markers (using the immunomax technique) was performed on 108 bone marrow preparations obtained from 36 children diagnosed with neuroblastoma (stage IV with bone marrow metastases). The analysis included expression of PGP 9.5 protein, substance P, chromogranin A, bombesin, galanin, neuropeptide Y (NPY), and vasoactive intestinal peptide in neuroblastoma metastatic cells defined by the expression of neurone specific enolase. RESULTS: Nineteen relapses occurred within 12 months of the end of treatment. Correlation between the various markers studied and early treatment failure, using Fisher's exact test, revealed that chromogranin A and NPY are strong indicators of an unfavourable prognosis in patients with stage IV neuroblastoma (p < 0.001 and p < 0.0002, respectively). CONCLUSION: Determination of metastatic cell immunophenotypes in bone marrow (particularly chromogranin A and NPY) may help establish the short term prognosis in children with neuroblastoma

The predicting role of substance P in the neoplastic transformation of the hypoplastic bone marrow

AIMS: To estimate the expression of substance P in the haematopoietic cells of hypoplastic bone marrow and define its relationship with the course of bone marrow hypoplasia. METHODS: Bone marrow specimens were obtained from 42 children with bone marrow hypoplasia who were hospitalised in the Department of Pediatric Oncology, Hematology and Transplantology, Poznan University of Medical Sciences, Poznan, Poland, between 1996 and 2003. Substance P and Ki‐67 expression were evaluated using immunochemical and hybridocytochemical assays. RESULTS: The expression of substance P (as evidenced by both immunocytochemical and hybridisation techniques) was confirmed in the cytoplasm of B lymphocytes in 8 of 11 children who developed acute leukaemia in 45 (SD 12) days. The percentage of substance P‐positive cells ranged from 67.6 to 95.8 (mean of 81.5% cells with immunocytochemistry and 84.3% with in situ hybridisation). The risk of development of leukaemia secondary to bone marrow hypoplasia was found to be significant (p<0.001) in those children who expressed substance P in normal‐looking lymphocytes at the initial bone marrow evaluation. CONCLUSIONS: The presence of substance P in B lymphocytes of hypoplastic bone marrow may predict its neoplastic transformation. A marked correlation between substance P‐positive bone marrow pattern and the expansion of tumour cells may prove the potential value of this oligopeptide in the pathogenesis of leukaemia

Ezrin—a useful factor in the prognosis of nephrotic syndrome in children: an immunohistochemical approach

BACKGROUND: Minimal change disease (MCD) and diffuse mesangial proliferation (DMP) are the most common pathomorphological forms of nephrotic syndrome glomerulopathies in children. The clinical course of DMP can be characterised by either DMP‐sensitivity (DMP‐S) or DMP‐resistance (DMP‐R) to steroids, resulting in an unfavourable course of the glomerulopathy. Although the clinical processes of DMP‐S and DMP‐R are initially identical, resistance to steroids may be foreseen by the immunohistochemical expression of cytoskeleton‐associated proteins in podocytes. AIMS: To estimate the immunohistochemical expression of ezrin in children with MCD, DMP and focal segmental glomerulosclerosis (FSGS) and to evaluate its usefulness in predicting resistance to steroids. MATERIALS AND METHODS: Renal biopsy specimens of patients with MCD (n = 15), DMP (n = 16) and FSGS (n = 6) were taken. The control tissue consisted of normal‐appearing cortex taken from kidneys resected for localised neoplasms (n = 6). The indirect immunohistochemical protocol for the use of a monoclonal antibody directed against ezrin was used. RESULTS: The immunohistochemical expression of ezrin in cases progressively reduced from MCD to DMP‐S to DMP‐R to FSGS. Except for DMP‐R and FSGS (p>0.05), the difference in ezrin expression in podocytes was significant. CONCLUSION: Ezrin can be a potent marker of podocyte injury (podocytopathy) and may help in the histological qualification of MCD, DMP and FSGS. The increased permeability of the filtration barrier in steroid‐resistant and proteinuric glomerulopathies may be a consequence of subcellular changes in podocyte‐associated proteins following decreased expression of ezrin

Vascular endothelial growth factor (VEGF)-C - a potent risk factor in children diagnosed with stadium 4 neuroblastoma.

To evaluate the immunohistochemical expression of VEGF-C, CD34 and VEGFR-2 in cancer tissue of children diagnosed with stadium 4 neuroblastoma (NB) and correlate their presence with the survival rate of children diagnosed with that stage of the disease. Eighteen children assigned to stadium 4 composed the study group. Fourteen patients (allocated to stadium 3) formed a control group. VEGF-C, CD34 and VEGFR-2 expressions were evaluated by immunohistochemical assay. Consecutive slides incubated with anti-CD34 and anti-VEGFR-2 antibodies revealed that the two markers were colocalized within endothelial layer of the blood vessels. On the other hand, VEGF-C was expressed exclusively in tumour cells. As demonstrated by Fisher's exact test, the risk of NB treatment failure (progression or relapse) as well as tumour related death, when all the patients were considered, was found to be significant in VEGF-C positive patients. VEGF-C expression in NB constitutes a potent risk factor and may direct future anti-angiogenic treatment strategy. The proximity of VEGF-C and CD34/VEGFR-2 of NB could be the equivalent of a potentially interesting VEGF-C fashion involving a tumour cell invasion into the blood vessels in an early phase of metastases promoting