An experimental model of autoimmune pancreatitis in the rat

Autoimmune pancreatitis (AIP), a recently defined disease of unknown etiology, is characterized by inflammatory infiltrates in the pancreas with conspicuous involvement of the ducts. The disease clinically manifests in humans as epigastric pain, weight loss, and jaundice. This report describes the development of a novel animal model of this disease in the rat, which we have termed experimental autoimmune pancreatitis. Adoptive transfer of amylase-specific CD4(+) T cells was able to confer pancreatitis to naive syngeneic recipient animals. No treatments before the adoptive transfer of T cells were necessary for disease to ensue, and the severity of disease was proportional to the number of T cells administered. The pancreatic lesions of rats with experimental autoimmune pancreatitis were characterized histologically as overwhelmingly lymphocytic with occasional plasma cells, neutrophils, and mast cells. Acinar tissue destruction and ductular inflammation were common features, with less frequent involvement of larger ducts. Immunohistochemical analysis revealed the presence of CD4(+) T cells in large numbers as well as CD8(+) T cells, macrophages, and dendritic cells. Expression of MHC I and MHC II also increased at the site of the lesion. Clinically, the disease manifested as either failure to gain weight at a rate concomitant with control animals or as outright weight loss. Thus, administration of activated CD4(+) T cells specific for the pancreatic enzyme amylase can induce pancreatitis in the rat in a manner that is reminiscent of human AIP.     

Identification of a gene from Xp21 with similarity to the tctex-1 gene of the murine t complex

Long range physical mapping within the p21 region of the X chromosomeIdentified a CpG rich Island approximately 180 kb centromericto the chronic granulomatous disease (CGD) locus. The segmentsadjacent to the CpG Island hybridized to discrete bands In DNAsof several species and when used to screen retinal cDNA librariesled to the Identification of cDNAs that detected a mRNA of 2.1kb in many tissues. Molecular characterization of correspondinggenomic clones of this novel human gene confirmed the originof the cDNA clones and Indicated a genomic structure with fiveexons spanning a total of 9 kb. The complete cDNA sequence revealedthat this gene contained a putative open reading frame of 116amino acids with a 3' untranslated region of 1.74 kb. The aminoacid sequence shows a high degree of similarity to the predictedproduct of the tctex-1 gene of the mouse t complex. As linkagestudies and patients with deletions have Implicated the Xp21region as containing the retInltls plgmentosa defect (RP3),the gene was assessed as a candidate disease gene In RP3 families.A single base pair polymorphism was Identified within the codingregion but no disease associated changes were found by singlestrand conformational polymorphism and sequencing analysis ofamplified exons of 20 RP patients. Analysis of a dinucleotiderepeat polymorphism within this gene In families affected withRP3 suggested refinement of the RP3 region.     

Characterization of FMR1 proteins isolated from different tissues

FMR1 protein expression was studied in different tissues. Inhuman, monkey and murine tissues, high molecular mass FMR1 proteins(67–80 kDa) are found, as shown in lymphobiastoid celiiines. The identity of these proteins was confirmed by theirabsence in tissues from patients with the fragile X syndromeand a FMR1 knock-out mouse. An IIe367Asn substitution in theFMR1 protein did not aiter the transiation, processing and localizationof FMR1 proteins in lymphoblastoid cells from a patient carryingthis mutation. All the high molecular mass FMR1 proteins isolatedfrom normal lymphoblastoid cells and cells from the patientwith the IIe367Asn substitution were able to bind RNA. However,the FMR1 proteins of the patient had reduced affinity for RNAbinding at high salt concentrations. In some human, monkey andmurine tissues low molecular mass FMR1 proteins (39–41kDa) were found, which had the same N terminus as the 67–90kDa isoforms, but differ in their C terminus and are thereforemost likely the result of carboxy-terminal proteolytic cleavage.These low molecular mass FMR1 proteins did not bind RNA, incontrast with the high molecular mass FMR1 proteins. The significanceof these low molecular mass proteins remains to be studied.     

Recovery of cryopreserved 96-well plates from −80° C

Summary A simple method is described for the effective recovery of cells cryopreserved in 96-well plates.     

Differential activation of human and guinea pig complement by pentameric and hexameric IgM

Human and mouse IgM can be polymerized as a hexamer in addition to a pentamer. Our previous work with mouse IgM measured activation of guinea pig complement by highly enriched preparations of hexamer and pentamer and showed that hexamer is >100-fold more active than pentamer. In this report pentamer and hexamer were compared for their capacity to activate complement in a homogeneic system, i.e. chimeric mouse V/human Cmu IgM pentamer and hexamer were assayed separately for their capacity to activate human (and guinea pig) complement. In both the homogeneic and the xenogeneic systems hexamer was more active than pentamer, but the magnitude of the difference between hexamer and pentamer depended on the complement source. Whereas chimeric hexamer activated guinea pig complement >100-fold more efficiently than did chimeric pentamer, this hexamer was only 4-13-fold more active than pentamer when assayed with human complement. Similarly, mouse hexamer, which was >100-fold more active than mouse pentamer with guinea pig complement, was only approximately 2-fold more active than mouse pentamer with human complement. Mouse hexameric and pentameric IgM were each approximately 20-fold more active with human complement than were the corresponding chimeric isoforms of IgM.     

Evaluation of RGS4 as a candidate gene for schizophrenia.

Several studies have suggested that the regulator of G-protein signaling 4 (RGS4) may be a positional and functional candidate gene for schizophrenia. Three single nucleotide polymorphisms (SNP) located at the promoter region (SNP4 and SNP7) and the intron 1 (SNP18) of RGS4 have been verified in different ethnic groups. Positive results have been reported in these SNPs with different numbers of SNP combinatory haplotypes. In this study, these three SNP markers were genotyped in 218 schizophrenia pedigrees of Taiwan (864 individuals) for association analysis. Among these three SNPs, neither SNP4, SNP7, SNP18 has shown significant association with schizophrenia in single locus association analysis, nor any compositions of the three SNP haplotypes has shown significantly associations with the DSM-IV diagnosed schizophrenia. Our results fail to support the RGS4 as a candidate gene for schizophrenia when evaluated from these three SNP markers.     

Galaxy: a platform for interactive large-scale genome analysis

Accessing and analyzing the exponentially expanding genomic sequence and functional data pose a challenge for biomedical researchers. Here we describe an interactive system, Galaxy, that combines the power of existing genome annotation databases with a simple Web portal to enable users to search remote resources, combine data from independent queries, and visualize the results. The heart of Galaxy is a flexible history system that stores the queries from each user; performs operations such as intersections, unions, and subtractions; and links to other computational tools. Galaxy can be accessed at http://g2.bx.psu.edu.     

Effect of influenza virus vaccine on the expression of human immunodeficiency virus co-receptor CCR5.

BACKGROUND: Administration of influenza vaccine to human immunodeficiency virus (HIV)-infected children can lead to increased viral load. CCR5 and CXCR4 are known to play an important role in HIV cell entry and viral replication. OBJECTIVE: To determine the effects of influenza vaccine on chemokine receptors and on viral load in HIV-infected children. METHODS: Eight HIV-infected children receiving stable therapy and 11 healthy adults were enrolled. Chemokine expression and immune activation were determined before and 48 hours after influenza vaccination. CCR5 and beta-chemokine gene expression were analyzed using real-time polymerase chain reaction. Viral load was measured at baseline, 48 hours, and 6 to 12 weeks. RESULTS: Forty-eight hours after influenza vaccination, mean CCR5 expression was significantly decreased on the CD3 (21.1% vs 11.3% in HIV-infected children; P = .02; and 18.3% vs 10.7% in controls; P = .008) and CD4 (13.0% vs 3.6% in the HIV group; P = .04; and 13.6% vs 6.5% in controls; P = .02) lymphocytes. This was observed in conjunction with an increase in HLA-DR expression on T lymphocytes in HIV-infected children (P = .046). No significant changes were observed in HIV viral load, CD3 and CD8 lymphocyte counts, expression of interleukin 2 receptor and CXCR4, or gene expression of CCR5 and beta-chemokines 48 hours after vaccination. CONCLUSIONS: Influenza virus vaccine markedly decreased chemokine receptor CCR5 expression on CD4 T lymphocytes. However, this immunomodulatory effect does not seem to affect overall viral replication in HIV-infected children who received highly active antiretroviral therapy.