Correlation of the level of Reg3α protein in plasma with gastrointestinal acute graft-versus-host disease / 中国实验血液学杂志

This study was purposed to explore the correlation of regenerating Islet-derived 3-alpha(Reg3α) protein level in plasma with the diagnosis and prognosis of the gastrointestinal acute graft-versus-host disease (GI-aGVHD) after all-HSCT, 103 patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) were observed in our hospital from December 2011 to December 2012. Peripheral blood samples were routinely collected at 9 d before allo-HSCT, 0 d, 14 d, 28 d after allo-HSCT as well as in aGVHD and at the 1 and 4 weeks after aGVHD therapy. The plasma concentrations of Reg3α were measured by using ELISA kit. The results indicated that among the 103 patients, 17 cases never developed aGVHD symptoms (no-aGVHD), 27 cases presented with non-aGVHD associated diarrhea, 10 cases presented with isolated skin aGVHD, 17 cases developed grades I-II GI-aGVHD, 32 cases with grades III-IV GI-aGVHD. The plasma concentrations of Reg3α in group of patients with GI-aGVHD and group of non-aGVHD diarrhea were 111.5 (54.7-180.2) and 23.9 (14.5-89.5) ng/ml respectively with significant difference (P < 0.001). The plasma concentrations of Reg3α in 17 patients of grades III-IV GI-aGVHD who experienced a complete or partial response and 7 patients who had no response to therapy at 4 weeks were 137.2(51.7-205.4) and 679.4(122.3-896.8) ng/ml respectively with the significant difference (P = 0.028). All of the patients who had no response to therapy died of aGVHD associated multiple organ failure. The area under the ROC curve was 0.902 when plasma concentration of Reg3α was set at 87.73 ng/ml. The sensitivity was 81.48% and the specificity was 82.86% when the critical value was used in diagnosis of grades III-IV GI-aGVHD. The probability of grades III-IV GI-aGVHD had statistical difference above and below 87.73 ng/ml after allo-HSCT (P < 0.001). It is concluded that the increase of plasma Reg3α level after transplantation suggests the incidence of grades III-IV GI-aGVHD. The high level of plasma Reg3α protein in patients with grades III-IV GI-aGVHD after the immunosuppressive treatment for four weeks indicates a poor prognosis. The plasma concentrations of Reg3α can be used as a specific biomarker of GI-aGVHD.

The splicing factor Prp31 is essential for photoreceptor development in Drosophila

Retinitis pigmentosa is a leading cause of blindness and a progressive retinal disorder, affecting millions of people worldwide. This disease is characterized by photoreceptor degeneration, eventually leading to complete blindness. Autosomal dominant (adRP) has been associated with mutations in at least four ubiquitously expressed genes encoding pre-mRNA splicing factors-Prp3, Prp8, Prp31 and PAP1. Biological function of adRP-associated splicing factor genes and molecular mechanisms by which mutations in these genes cause cell-type specific photoreceptor degeneration in humans remain to be elucidated. To investigate the in vivo function of these adRP-associated splicing factor genes, we examined Drosophila in which expression of fly Prp31 homolog was down-regulated. Sequence analyses show that CG6876 is the likely candidate of Drosophila melanogaster Prp31 homolog (DmPrp31). Predicted peptide sequence for CG6876 shows 57% similarity to the Homo sapiens Prp31 protein (HsPrp31). Reduction of the endogenous Prp31 by RNAi-mediated knockdown specifically in the eye leads to reduction of eye size or complete absence of eyes with remarkable features of photoreceptor degeneration and recapitulates the bimodal expressivity of human Prp31 mutations in adRP patients. Such transgenic DmPrp31RNAi flies provide a useful tool for identifying genetic modifiers or interacting genes for Prp31. Expression of the human Prp31 in these animals leads to a partial rescue of the eye phenotype. Our results indicate that the Drosophila CG6876 is the fly ortholog of mammalian Prp31 gene.

Small interfering RNA-mediated islet neogenesis associated protein gene silencing inhibits the proliferation of INS-1 islet cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of small interfering RNA (siRNA)-mediated islet neogenesis associated protein (INGAP) gene silencing on the proliferation of islet cells.</p><p><b>METHODS</b>Different siRNAs targeting INGAP gene were designed and transfected into INS-1 islet cells, and the expression levels of INGAP mRNA and protein following the transfection were detected using RT-PCR, flow cytometry and Western blotting. The proliferation of the transfected INS-1 cells was evaluated using MTT assay.</p><p><b>RESULTS</b>Compared with those in the irrelevant siRNA, empty vector control, and un-transfected groups, the expression levels of INGAP mRNA and protein in the cells transfected with siRNA6 were reduced significantly. The cell proliferation rate significantly increased after transfection with siRNA6 (P<0.05).</p><p><b>CONCLUSION</b>siRNA targeting INGAP can effectively down-regulate INGAP expression and inhibit the proliferation of INS-1 cells.</p>

Cloning and secretory expression of islet neogenesis-associated protein in Pichia pastoris / 南方医科大学学报

<p><b>OBJECTIVE</b>To clone the recombinant human islet neogenesis-associated protein (rhINGAP) gene for its secretory expression in Pichia pastoris.</p><p><b>METHODS</b>INGAP gene was amplified with PCR and inserted between Xho I and EcoR I downstream sites of the alpha factor of the recombinant plasmid alpha/pUC18. The fusion gene of alpha factor and INGAP was subsequently inserted between BamH I and EcoR I sites of the plasmid pPIC9K of P. pastoris. After confirmation with restriction enzyme digestion and sequencing, the positive recombinant plasmid that integrated INGAP gene was linearized with Sal I digestion and transformed into the yeast host strain GS115 through electroporation. The yeast transformants that harbored the INGAP gene with high copies were selected with the auxotroph medium and G418, followed then by PCR verification of the positive transformants, from which the expression of recombinant human INGAP was induced with methanol as the only carbone source. The antigenic activity of the desired protein was then detected using Western blotting and enzyme-linked immunosorbent assay (ELISA).</p><p><b>RESULTS AND CONCLUSION</b>The recombinant expression plasmid INGAP/pPIC9K was successfully constructed, and 3 positive transformants were obtained. The expressed protein showed good antigenic activity as confirmed by Western blotting and ELISA.</p>

Reg IV, a differentially expressed gene in colorectal adenoma / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To discover and identify differentially expressed genes associated with colorectal adenoma formation and the role of RegIV in colorectal adenoma differentiation.</p><p><b>METHODS</b>A subtracted cDNA library was constructed with cDNAs that were isolated from either the normal mucosa or adenoma tissue of a single patient. Suppressive subtractive hybridization (SSH) combined with virtual northern blotting was used to characterize differentially expressed genes and contigs were assembled by electronic cloning (in silico cloning) with the EST database. Semi-quantitative RT-PCR was performed in 9 colorectal adenomas.</p><p><b>RESULTS</b>The amino acid sequence was determined with open reading frame (ORF) prediction software and was found to be 100% homologous to the protein product of RegIV (a novel gene isolated from a large inflammatory bowel disease library). RegIV was found to be highly expressed in all of the adenoma samples (9/9) compared with the normal mucosa samples, while 5/6 cases showed RegIV to be more strongly expressed in adenocarcinoma.</p><p><b>CONCLUSION</b>RegIV may play an important role in the initiation of colorectal adenoma differentiation, and its detection may be useful in the early diagnosis of colorectal adenoma formation.</p>