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O Olerup

Publications and source records attributed to O Olerup.

At least 55 records · Page 3Linked to original sources
PubMed1994

The DQA1*0104 allele is carried by DRB1*1001- and DRB1*1401-positive haplotypes in Caucasians, Africans and Orientals.

The DQA1*0104 allele is known to differ from DQA1*0101 by a single nucleotide in the sequenced part of the first exon. DQA1*0104 has a guanine in the second position of the second expressed codon, whereas DQA1*0101 and all other sequenced DQA1 alleles have an adenine in that position, changing aspartic acid to glycine. The DQA1*0104 allele was originally described in African Americans with the DRB1*12, DRB3*0101, DQA1*0104, DQB1*0501, DRB1*12, DRB3*0202, DQA1*0104, DQB1*0605 or DRB1*14, DQA1*0104, DQB1*0503 haplotypes. When developing DQA1 typing by PCR amplification with sequence-specific primers (PCR-SSP), we observed that all DR10- and DR14-positive samples carried the DQA1*0104 allele, whereas all DRB1*01-positive DNAs carried the closely related DQA1*0101 allele. In the present study, samples representing the major ethnic groups with DR-DQ haplotypes known to carry the DQA1*0104 allele or the very similar DQA1*0101 allele were investigated by TaqI RFLP analysis, PCR-SSP typing and nucleotide sequencing. The DQA1*0104 allele was found to differ from DQA1*0101 not only in the second expressed codon, but also by a productive mutation in the signal peptide. All investigated DRB1*1001-(n = 24) and DRB1*1401-positive (n = 25) haplotypes, defined by homozygosity or association, of Caucasian, African or Oriental origin carried the DQA1*0104 allele, whereas the DQA1*0101 allele was found on all DRB1*01-positive (n = 32) haplotypes. These findings demonstrate that in the assignment of HLA class II alleles, polymorphism outside the second exon sometimes must be considered.(ABSTRACT TRUNCATED AT 250 WORDS)

Alleles↗
PubMed1994

HLA-DOB1 "low-resolution' typing by PCR amplification with sequence-specific primers (PCR-SSP).

In the study described here primers were designed for DQB1 'low-resolution', i.e. generic, typing by PCR amplification with sequence-specific primers (PCR-SSP) considering all the currently recognized DQB1 alleles, i.e. 0501-0504, 0601-0609, 0201, 0301-0305 and 0401-0402. This resolution was achieved by performing eight PCR reactions per individual. The DQB1 alleles corresponding to the serological specificities DQ4, DQ5, and DQ6 were uniquely identified, whereas the DQ2, DQ7, DQ8 and DQ9 specificities were amplified by two primer mixes. All homozygous and heterozygous combinations of the serological series DQ1 to DQ9 could be distinguished. The yield of amplified products were increased compared to our previously described DQB1 'high-resolution' typing technique by lengthening many of the primers, modifying the PCR cycling parameters and by including glycerol in the PCR reaction mixtures. Thirty-one cell lines and 90 donor spleen cells were investigated by the DQB1 'low-resolution' PCR-SSP technique as well as by TaqI DRB-DQA-DQB RFLP analysis. The concordance between PCR-SSP typing and RFLP analysis was 100%. The cell lines and 20 of the spleen cells were typed twice with complete reproducibility. No false positive or false negative typing results were obtained. DQB1 'low-resolution' PCR-SSP typing, including DNA extraction, PCR amplification, gel detection, documentation and interpretation, were performed in 2 h which renders the PCR-SSP technique suitable also for the genotyping of cadaveric organ donors.

Alleles↗
PubMed1994

No association with HLA class II alleles in Swedish patients with cutaneous manifestations of Lyme borreliosis.

The possibility of an association between manifestations of Lyme borreliosis and HLA class II alleles has been investigated with varying results. In the present study, we used genomic typing techniques to determine the DR, DQ and DP allele frequencies in 29 patients with erythema migrans and 36 patients with acrodermatitis chronica atrophicans. We did not find a significant deviation from controls in the distribution of the HLA class II alleles in any of these disease manifestations, nor in the subgroup of 8 patients with acrodermatitis chronica atrophicans and long-standing arthritis. With the additional information obtained by the typing techniques used, our results are thus in accord with those studies where no association between the development of the late disease manifestation acrodermatitis chronica atrophicans and HLA class II alleles has been found.

Acrodermatitis↗
PubMed1994

Characterization of regulatory T-cell responses in humans induced by the P. Falciparum blood stage antigen Pf155/RESA.

T-cells have a major role both as helper cells for efficient antibody production and as inducers and effector cells in antibody-independent malaria immunity. Thus, antigens to be included into a subunit vaccine must contain T-cell epitopes to become effectively immunogenic. The P. falciparum blood stage vaccine antigen Pf155/RESA has been shown to contain T-helper epitopes inducing T-dependent anti-malarial antibodies in vitro. We have also shown that synthetic peptides representing sequences from the amino-acid repeat regions of Pf155/RESA stimulate T-cells from P. falciparum primed donors to proliferate, to release IFN-gamma and/or IL-4. In individual donors there was no correlation between these different activities. Rather, they were frequently negatively associated. However, IL-4 secretion could be induced in T-cells from donors who had elevated concentrations of serum antibodies to the same peptide as used for T-cell activation. Taken together the results support the occurrence of malaria-specific CD4+ T-cell subsets (e.g. TH1 and TH2) in humans similar to what has been found in mice and suggest the involvement of TH2-type helper cells in the induction of some important P. falciparum specific antibodies. CD4+ T-cells recognize the antigen in the context of MHC class II molecules. However, in human outbred populations no consistent MHC restrictions of anti-Pf155/RESA immune responses could be demonstrated. This is not surprising in view of the extensive polymorphism of the HLA system. Neither were there any obvious MHC class II restrictions seen when antibody- and t-cell responses were measured in naturally primed monozygotic twins.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Susceptibility to demyelinating polyneuropathy in plasma cell dyscrasia may be influenced by amino acid position 9 of the HLA-DR beta chain.

Fifty-five patients with plasma cell dyscrasias were investigated by genomic typing for HLA-DR and -DQ genes by restriction fragment length polymorphism, neurophysiology and for presence of anti-myelin-associated glycoprotein (MAG) antibodies. In 26 patients, a polyneuropathy (PN) of demyelinating type was established. Among these individuals, an association was found with the presence of a tryptophan amino acid residue at position 9 of the DR beta chain (P < 0.01). This position is part of the first hypervariable region of the DR beta chain, and may be of importance in determining preferential peptide-binding capacity of the HLA-DR molecule. The presence of anti-MAG antibodies in 15 out of 17 patients with an IgM M-component and demyelinating PN (14 of these 15 individuals carrying a tryptophan at position 9) supports the pathogenic role of an autoimmune response against MAG. The finding of an HLA class II association may indicate a pathogenic role of T cell immunity in this condition.

Adult↗
PubMed1993

HLA-DR, -DQ and -DP alleles in nickel, chromium, and/or cobalt-sensitive individuals: genomic analysis based on restriction fragment length polymorphisms.

The increased concordance rate of nickel sensitivity in monozygotic compared to dizygotic twins indicates a genetic causal component. We have previously described an association in nickel-sensitive subjects with an HLA-DQA restriction fragment length polymorphism (RFLP) (4.5-kb TaqI band, DQA1*0501). The purpose of the present study was to investigate if our previous finding could be confirmed in an independent study, and also to investigate the distribution of HLA class II alleles in chromium- and cobalt-sensitive individuals. Using TaqI- or MspI-digested DNA and DQA, DQB, DRB, DPA and DPB cDNA probes alleles were defined by RFLP analysis. The association with the DQA1*0501 allele was not confirmed in the new group of 37 nickel-sensitive subjects (compared to 150 new controls), nor when the two groups of patients were combined. The distribution of HLA class II alleles and DR-DQ haplotypes were similar in the pooled group of 70 nickel-sensitive subjects and the combined control groups (n = 250). No significant changes in the distribution of HLA class II allele among the chromium- (n = 26) and/or cobalt- (n = 38) sensitive individuals were found. Our results indicate that it is unlikely that the tendency to develop metal sensitivity is associated with alleles of the HLA class II region.

Alleles↗
PubMed1993

HLA-DQB1 and -DQA1 typing by PCR amplification with sequence-specific primers (PCR-SSP) in 2 hours.

In the present study PCR primers were designed for detecting all phenotypically expressed DQB1 and DQA1 allelic variability, 19 and 10 alleles, respectively, by PCR amplification with sequence-specific primers (PCR-SSP). For DQB1 typing, each sample was amplified by a first set of 14 PCR primer pairs, followed in some cases by two to six additional PCR reactions. The first 14 primer pairs allowed the identification/separation of all but a few of the recently described DQB1 alleles: DQB1*0504, DQB1*0605, DQB1*0606 and DQB1*0607 would not be identified; DQB1*0603 and DQB1*0608; and DQB1*0301 and DQB1*0304, respectively, would not be distinguished. Therefore an additional set of eight DQB1 primer pairs was used for a complete DQB1 typing, including all homozygous and heterozygous combinations. For DQA1 typing, 12 PCR reactions were performed per sample, 10 for detecting variability within the second exon and two for identifying first exon polymorphism. All homozygous and heterzoygous combinations of DQA1 alleles could be resolved by these primer pairs. In addition, four primer mixes were designed for determining codon 57 of the HLA-DQB1 gene. Thirty cell lines and 120 individuals were investigated by the DQB1 and DQA1 PCR-SSP technique, as well as with the HLA-DQ beta 57 primers. The concordance between PCR-SSP typing and assigning DQB1 and DQA1 alleles from TaqI DRB-DQA-DQB RFLP analysis was 100%. The reproducibility was 100% in 30 samples investigated on two separate occasions. Amplification patterns, investigated in 15 nuclear families, segregated according to dominant Mendelian inheritance. DQB1 and DQA1 PCR-SSP typing can be performed in 2 hours, including DNA extraction, PCR amplification and post-amplification processing. The method is technically simple and the typings are easy to interpret. The cost for typing one individual is low and is independent of the number of samples analyzed simultaneously, i.e. the technique is well-suited for routine clinical use.

Adult↗
PubMed1993

Immunoglobulin M and G antibody responses to Plasmodium falciparum glutamate-rich protein: correlation with clinical immunity in Gambian children.

The aims of the present study were to describe the age-related immunoglobulin M (IgM) and IgG response to part of a 220-kDa glutamate-rich protein (GLURP) from Plasmodium falciparum and to determine possible correlations of possession of these antibodies with malaria morbidity. IgM and IgG levels were measured with a recombinant fusion protein consisting of the carboxy-terminal 783 amino acids of the GLURP. Samples for the study were obtained during a longitudinal malaria morbidity survey performed in The Gambia; cross-sectional surveys were performed at the beginning of the transmission season in May and in October. Seropositivity rates increased with age to a maximum of 77% for IgM and 95% for IgG in adults. High prevalences of seropositivity were associated with certain human leukocyte antigen class II alleles (DRw8, DR9, DR7, DR4, DQw7, and DQw2) or haplotypes. The relationship between anti-GLURP489-1271 antibodies and clinical immunity is not clear; asymptomatically infected children aged 5 to 8 years had significantly higher levels of IgG than clinically ill children of the same age, suggesting that antibodies to the carboxy-terminal part of the GLURP may contribute to immunity to P. falciparum. However, this was not significant for younger children.

Adolescent↗
PubMed1993

HLA and MS.

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HLA-D Antigens↗