Down-regulation of antigen-specific antibody production by TCR antagonist peptides in vivo

The efficacy of TCR antagonist peptides in inhibition of antigen-specific antibody production and T cell responses in vivo was evaluated. Among amino acid-substituted analogs of a peptide corresponding to residues 119 - 133 of bovine beta-lactoglobulin (p119 - 133), pR124Q and pD129S, prepared by substitution of Gln and Ser for Arg(124) and Asp(129), respectively, have been shown to display TCR antagonist activity for three out of four distinct p119 - 133-specific T cell clones and for polyclonal T cells derived from p119 - 133-immunized C57BL / 6 mice. Both pD129S and pR124Q inhibited in vivo priming and subsequent activation of T cells by p119 - 133 when co-injected with p119 - 133 into mice, as shown by the decreased proliferation of T cells in response to p119-133 in vitro. pD129S significantly inhibited production of anti-p119 - 113 antibodies of IgG1, IgG2b and IgE isotype in vivo when co-injected into mice together with p119 - 133 at the time of the first immunization. However, pR124Q was totally ineffective in inhibition of the antibody responses. Anti-p119 - 133 antibodies from p119 - 133-immunized mice could bind to pR124Q but not to pD129S, suggesting that the difference in cross-reactivity is responsible for the different effect of these two peptides on specific antibody production. Our findings demonstrate that a single TCR antagonist peptide can inhibit antigen-specific polyclonal antibody production when this antagonist peptide does not cross-react with the antibody elicited in response to an antigenic peptide.     

Skeletal manifestations in Fryns syndrome

We report on a female baby with Fryns syndrome who died soon after birth. The patient had short limbs, coarse face, hypoplastic lungs, diaphragmatic hernia, and acral hypoplasia. Literature review disclosed varying degrees of skeletal manifestations in Fryns syndrome; short limbs may be a component of Fryns syndrome. © 1995 Wiley-Liss, Inc.     

A common Ile796Val polymorphism of the human SREBP cleavage-activating protein (SCAP) gene

We identified a new common amino acid polymorphism of isoleucine/valine at codon 796 in exon 16 of the gene for human sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP), a central regulator of lipid synthesis and metabolism in animal cells. It can be detected as an MslI restriction fragment length polymorphism. The allelic frequencies were: isoleucine (A) allele, 0.57 and valine (G) allele, 0.43. This polymorphism may be useful for genetic studies of disorders affecting intracellular lipid metabolism and hyperlipidemia. Received: August 17, 1999 / Accepted: August 19, 1999     

Molecular cloning and expression analysis of a macrophage-colony stimulating factor receptor-like gene from rainbow trout, Oncorhynchus mykiss

The M-CSF and its receptor (M-CSFR, CSF-1R or c-fms proto-oncogene) system were initially implicated as essential in mammals for normal monocyte development as well as for pregnancy. To allow a comparison with the M-CSF and M-CSFR system of an oviparous animal, we cloned a M-CSFR-like gene from rainbow trout (Oncorhynchus mykiss). The gene was cloned from a cDNA library of head kidney. It contained an open reading frame encoding 967 amino acids with a predicted size of 109 kDa. The putative amino acid sequence of rainbow trout M-CSFR showed 54% amino acid identity to fugu (Takifugu rubripes) M-CSFR, 52% to zebrafish (Danio rerio) M-CSFR and 40% to mouse (Mus musculus) and human (Homo sapiens) M-CSFR. The M-CSFR-like gene was constitutively expressed in head kidney, kidney, intestine, spleen and blood. The gene was detected especially in the ovary of immature female rainbow trout. These results suggest that a M-CSFR-like receptor may be involved in female reproductive tracts even in an oviparous animal like fish.     

Stratum-specific likelihood ratios of the general health questionnaire in the community: help-seeking and physical co-morbidity affect the test characteristics

BACKGROUND: In evidence-based medicine, stratum-specific likelihood ratios (SSLRs) are now being increasingly recognized as a more convenient and generalizable method to interpret diagnostic information than an optimal cut-off and its associated sensitivity and specificity. We previously examined the SSLRs of the General Health Questionnaire (GHQ) in primary care settings. The present paper aims to examine if these SSLRs are generalizable to the community settings. METHODS: The Composite International Diagnostic Interview (CIDI) and the GHQ were administered on a representative sample of the Australian population in the Australian National Survey of Mental Health and Well-Being. We first compared the SSLRs of GHQ in urban Australia with the estimates that we had previously obtained from the developed urban centres in the WHO Psychological Problems in General Health Care study. If the SSLRs in the community were found to differ significantly from those in the primary care, we sought for explanatory variables. RESULTS: The SSLRs in urban Australia and in the urban centres in the WHO study were significantly different for three out of the six strata. When we limited the sample to those with physical problems who visited a health professional, however, the SSLRs in the Australian study were strikingly close to those observed for primary care settings. CONCLUSIONS: Different sets of SSLRs apply to primary care and general population samples. For general population surveys in developed countries, the results of the Australian National Survey represent the currently available best estimates. For developing countries or rural areas, the results are less definitive and an investigator may wish to conduct a pilot study.     

Enhanced poliovirus replication in cytomegalovirus-infected human fibroblasts.

Replication of poliovirus in human cytomegalovirus (CMV)-infected cells is enhanced 5-to 10-fold over replication in uninfected cells. Enhanced poliovirus replication in dually infected cells was not due to a difference in adsorption on infected cells and was supported by evidence of increased synthesis of polio-specific RNA. A functional CMV genome appeared to be required for the enhancement of polio replication since enhanced replication was not seen in cells infected with uv-irradiated CMV or in cultures treated with the inhibitors of CMV replication. Enhanced polio replication in CMV-infected cells may be due to the enhanced cellular metabolism in these cells.     

Exclusion of SMAD4 mutation as an early genetic change in human pancreatic ductal tumorigenesis

Pancreatic ductal carcinoma is one of the malignant diseases with the poorest prognosis. To develop effective methods for better treatment of pancreatic cancer patients, we tried to analyze the course of multistep carcinogenesis of the pancreatic ductal cells. IPMT (intraductal papillary-mucinous tumor) is thought to be one of the premalignant lesions of the pancreas, which would transform into carcinomas. Loss of 18q at the SMAD4 locus is known to be an early genetic change in pancreatic ductal carcinomas. It is not clear, however, whether or not the target gene for inactivation is SMAD4. Using 18 IPMTs, we analyzed LOH at the SMAD4 locus and observed frequent LOH (7/14, 50%). No mutations were observed in any of the tumors. Moreover, the expression level of the SMAD4 protein did not show a reduction in IPMTs. These results suggested that (i) inactivating mutation of the SMAD4 gene is a rather late genetic change in pancreatic carcinogenesis, and (ii) there may be an unknown tumor suppressor gene in 18q, other than SMAD4, that is involved in pancreatic ductal carcinogenesis.     

Role of cytokines in autoimmune myocarditis and cardiomyopathy

Cellular as well as humoral autoimmune responses are critically associated with the pathogenesis and progression of myocarditis and cardiomyopathy. Cytokines appear to play critical roles in accentuating or regulating autoimmune mechanisms in these disorders. However, depending on the triggers of autoimmune responses against the heart, such as viral or parasitic infections and experimental immunization with cardiac myosin, the effect of each cytokine on autoimmune myocardial disease may vary. Cytokines may represent new therapeutic targets in the treatment and prevention of autoimmunity-mediated myocarditis and cardiomyopathy, though the etiology and variability in the type of autoimmune responses should be taken into account in the development of cytokine/anti-cytokine treatment of these disorders.