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ABSTRACT: Elevated serum macrophage migration inhibitory factor (MIF) is associated with severe sepsis, but it is not clear whether bacteria stimulate synthesis of MIF by blood leukocytes directly or via induction of TNF. Here we assess production of MIF mRNA and protein by blood leukocytes from healthy human subjects (n=28) following exposure to bacteria commonly associated with sepsis (Escherichia coli and Streptococcus pneumoniae). Bacteria did not increase levels of MIF mRNA or secreted protein. CD14(+) monocytes were the main cell type producing MIF before and after stimulation. Exposure of leukocytes to TNF did not induce MIF. Hence elevated levels of serum MIF observed in sepsis may not reflect MIF produced by blood leukocytes stimulated directly by bacteria or TNF.
Cytokine 05/2009; 46(3):316-8. · 3.02 Impact Factor
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ABSTRACT: To identify a functional polymorphic site(s) within HSPA1A and/or HSPA1B which is in linkage disequilibrium with the silent mutation HSPA1B1267A>G and explains its association with septic shock.
The promoter region of HSPA1A and HSPA1B was sequenced in 100 healthy whites. Stimulation experiments were performed on 36 healthy subjects.
Sequencing the HSPA1A and HSPA1B promoter regions (approx. 500 bp upstream of the translation start site) identified ten novel and three known polymorphisms. Mononuclear cells were stimulated with lipopolysaccharide (10 microg/ml) for 4 and 8 h, and mRNA levels measured by reverse transcriptase polymerase chain reaction. Two polymorphisms, HSPA1A-27G>C and HSPA1A-327A>C, were found to be in strong linkage with HSPA1B1267A>G but, as with HSPA1B1267A>G, were not associated with stimulated mRNA levels. However, HSPA1B-179C>T, which is also in linkage with HSPA1B1267, was associated with stimulated HSPA1A and HSPA1B mRNA levels. Individuals homozygous for the C allele of HSPA1B-179C>T were associated with lower HSPA1A and HSPA1B mRNA levels than HSPA1B-179CT after 8 h lipopolysaccharide stimulation.
HSPA1B-179C>T is in linkage disequilibrium with HSPA1B1267A>G and is associated with variable production of HSPA1B and HSPA1A production. This suggests that HSPA1B-179C>T affects HSP70 production and is a key determinant of individual susceptibility to a variety of infectious and inflammatory diseases.
Intensive Care Medicine 09/2004; 30(9):1761-7. · 5.40 Impact Factor
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ABSTRACT: IL-10 inhibits the production of many pro-inflammatory cytokines. Polymorphisms in the IL10 gene promoter at positions -1082G-->A, -819C-->T and -592C-->A occur as three haplotypes, ATA, GCC and ACC. These influence several infectious and inflammatory diseases including community-acquired pneumonia, where a role for IL-10 is suggested by fluctuations in plasma levels of the cytokine. However, the effects of the haplotypes on IL-10 production are unclear. We stimulated peripheral blood mononuclear cells (PBMC) from at least five individuals homozygous for each of the three haplotypes with lipopolysaccharide (LPS, 10 microg/ml) or heat-killed Streptococcus pneumoniae (10(7)cfu/ml) and measured IL-10 mRNA by RT-PCR. Following S. pneumoniae stimulation, PBMC with the ATA haplotype had higher IL-10 mRNA levels than those with the GCC haplotype at 4 h (independent t-test; P=0.024), or the ACC haplotype at 4 h ( P<0.0001) and 8 h ( P=0.007). Following LPS stimulation, IL-10 mRNA levels were not significantly influenced by the IL10 haplotype, but similar trends were observed, consistent with the variable outcome of published studies. The results suggest that the -819 and/or -592 alleles affect transcription.
Immunogenetics 12/2003; 55(9):629-32. · 2.93 Impact Factor
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Vance B Matthews,
Campbell S Witt,
Martyn A H French,
Helmut K G Machulla,
Emilio G De la Concha, Karey Y Cheong,
Patricia Vigil,
Peter N Hollingsworth,
Kevin J Warr,
Frank T Christiansen,
Patricia Price
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ABSTRACT: This study investigates the hypothesis that alternative alleles of one or more genes in the central major histocompatibility complex (MHC) predispose carriers to IgA deficiency (IgAD) or IgA Nephropathy (IgAN). Australian caucasian IgAD, IgAN patients, and controls were typed at HLA loci, single nucleotide polymorphisms, and microsatellites in the MHC. Alleles of the D6S273 microsatellite exhibited strong associations with IgAD and IgAN. D6S273*129 and *139 were more frequent in IgAD and less frequent in IgAN patients than controls. The reverse was true for D6S273*133 and *131. Alleles of other microsatellites exhibited weak associations with IgAD or IgAN. D6S273*129 is found on the 65.1 ancestral haplotype [HLA-B14(65),DR1], which has been reported to be increased in IgAD, but the majority of IgAD patients with D6S273*129 did not have other alleles of the haplotype. D6S273*139 is characteristic of the 8.1 ancestral haplotype (HLA-A1,B8,DR3), which was common in IgAD and rare in IgAN patients. Further studies of the 8.1 haplotype in Australian, German and Spanish caucasian subjects revealed that HLA-DR3, in the absence of -B8, is not associated with IgAD. However -B8 is associated with IgAD in the absence of -DR3, consistent with a susceptibility locus in the central MHC. Provisional mapping within this region is discussed.
Human Immunology 06/2002; 63(5):424-33. · 2.84 Impact Factor
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ABSTRACT: The contribution of MHC class II haplotypes to susceptibility to type I diabetes has been clearly established, and interest has now focused on the effects of additional genes in the MHC region. We have investigated the central MHC alleles on 8.1 ancestral haplotype (HLA-A1, B8, DR3, DQ2), as it is well conserved in Caucasian populations. The HLA-DR3-DQ2 genotype is a recognized risk factor for type I diabetes. Single nucleotide polymorphisms and microsatellites in the MHC were used to map segments of the 8.1 ancestral haplotype carried by type I diabetic and control subjects expressing either HLA-B8 or DR3, but not both these markers. In this way we controlled for the diabetogenic effect of carriage of DR3. Alleles of the 8.1 ancestral haplotype between TNFA-308/D6STNFa and HLA-B were carried with significantly greater frequency in B8−, DR3+ type I diabetic patients compared with B8−, DR3+ controls. This interval was marked by a BAT1 gene polymorphism and a MIB microsatellite allele.
Human Immunology 01/2002; · 2.84 Impact Factor
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Vance B. Matthews,
Campbell S. Witt,
Martyn A.H. French,
Helmut K.G. Machulla,
Emilio G. De la Concha, Karey Y. Cheong,
Patricia Vigil,
Peter N. Hollingsworth,
Kevin J. Warr,
Frank T. Christiansen,
Patricia Price
[show abstract]
[hide abstract]
ABSTRACT: This study investigates the hypothesis that alternative alleles of one or more genes in the central major histocompatibility complex (MHC) predispose carriers to IgA deficiency (IgAD) or IgA Nephropathy (IgAN). Australian caucasian IgAD, IgAN patients, and controls were typed at HLA loci, single nucleotide polymorphisms, and microsatellites in the MHC. Alleles of the D6S273 microsatellite exhibited strong associations with IgAD and IgAN. D6S273*129 and *139 were more frequent in IgAD and less frequent in IgAN patients than controls. The reverse was true for D6S273*133 and *131. Alleles of other microsatellites exhibited weak associations with IgAD or IgAN. D6S273*129 is found on the 65.1 ancestral haplotype [HLA-B14(65),DR1], which has been reported to be increased in IgAD, but the majority of IgAD patients with D6S273*129 did not have other alleles of the haplotype. D6S273*139 is characteristic of the 8.1 ancestral haplotype (HLA-A1,B8,DR3), which was common in IgAD and rare in IgAN patients. Further studies of the 8.1 haplotype in Australian, German and Spanish caucasian subjects revealed that HLA-DR3, in the absence of -B8, is not associated with IgAD. However -B8 is associated with IgAD in the absence of -DR3, consistent with a susceptibility locus in the central MHC. Provisional mapping within this region is discussed.
Human Immunology.
