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W M Prodinger

Publications and source records attributed to W M Prodinger.

34 records · Page 2Linked to original sources
PubMed1996

Molecular epidemiology of Klebsiella pneumoniae producing SHV-5 beta- lactamase: parallel outbreaks due to multiple plasmid transfer.

Over a period of 22 months, 32 patients treated in three independent intensive care units of the Innsbruck University Hospital were infected with extended-spectrum beta-lactamase-producing members of the family Enterobacteriaceae (30 Klebsiella pneumoniae isolates, 1 Klebsiella oxytoca isolate, and 1 Escherichia coli isolate). As confirmed by sequencing of a bla gene PCR fragment, all isolates expressed the SHV-5-type beta-lactamase. Genomic fingerprinting of epidemic strains with XbaI and pulsed-field gel electrophoresis grouped 20 of 21 isolates from ward A into two consecutive clusters which included 1 of 3 ward B isolates. All six K. pneumoniae isolates from ward C formed a third cluster. Stool isolates of asymptomatic patients and environmental isolates belonged to these clusters as well. Additionally, 2,600 routine K. pneumoniae isolates from the surrounding provinces (population, 900,000) were screened for SHV-5 production. Only one of six nonepidemic isolates producing SHV-5 beta-lactamase was matched with the outbreak strains by genomic fingerprinting. Plasmid fingerprinting, however, revealed the epidemic spread of a predominant R-plasmid, with a size of approximately 80 kb, associated with 29 of the 30 K. pneumoniae isolates. This plasmid was also present in the single K. oxytoca and E. coli isolates from ward C and in three nonepidemic isolates producing SHV-5. Our results underline that strain typing exclusively on the genomic level can be misleading in the epidemiological investigation of plasmid-encoded extended-spectrum beta-lactamases. Our evidence for multiple events of R-plasmid transfer between species of the family Enterobacteriaceae in this nosocomial outbreak stresses the need for plasmid typing, especially because SHV-5 beta-lactamase seems to be regionally spread predominantly via plasmid transfer.

Base Sequence↗
PubMed1995

Expression of Epstein-Barr virus nuclear antigen-2 (EBNA2) induces CD21/CR2 on B and T cell lines and shedding of soluble CD21.

Stable transfection of Epstein-Barr virus (EBV) nuclear antigen 2 (EBNA2) expressed as a fusion protein with the hormone-binding domain of the estrogen receptor was used to study expression of CD21 and other surface markers in different cell lines. Special emphasis was placed on cell lines with a normally low expression of CD21, especially on T cell lines. After induction of EBNA2, a substantial increase in CD21 mRNA was observed, as well as increased production of membrane CD21. This was found not only in cell lines of B cell origin, but also in the T cell line Jurkat. The amount of CD21 was quantitated by means of a fluorescence immunoassay, and found to correlate with the presence of EBNA2 protein. A decrease in EBNA2 abundance was associated with complete loss of cell-associated CD21. As we could also detect large amounts of soluble CD21 (sCD21) in the supernatant of the transfected cell lines, which exceeded the total amount contained in the respective cell lysates, this indicates considerable shedding of the newly synthesized receptor molecules induced by EBNA2, comparable to the situation described for CD23. It further provides an explanation of the recent findings of increased sCD21 levels in sera of patients with EBV-associated disease, and suggests a possible additional function of EBNA2 in vivo.

Antigen Presentation↗
PubMed1995

Reduced CD21 (CR2) and CD54 (ICAM-1) expression in MT2 cells with HIV-1 or HIV-2 strains.

Alterations in the expression of cell-surface receptors have been reported in HIV-infected cells for CD4, CD25 (IL-2 receptor), CD2, CD3 and CD8 and CD26. In the present study we provide evidence that CD21 is down-regulated in the human T-lymphoblastoid cell line MT2 after infection with HIV-1 and -2 isolates. The same effect was observed with ICAM-1 (CD54). CD21 expression was monitored by means of fluorescence intensity, its functional ability to bind to C3d and by quantitative measurement of CD21-antigen in supernatants and cell lysates using an immunoassay. In addition, the decrease of CD21 and ICAM-1-specific mRNA suggests a mechanism at a transcriptional level. Our data suggest that HIV might have a direct influence on the receptor expression.

Cell Line, Transformed↗
PubMed1995

Complement C7 M/N allotyping in infectious diseases.

The allotypes of the C7 M/N polymorphism are determined by ELISA by comparing the reaction pattern of the allospecific monoclonal antibody WU 4-15 with that of polyclonal anti-C7 IgG. In order to find disease associations of the two alleles C7*M and C7*N we tested 528 hospitalised patients, most of them suffering from infectious diseases. No significant association of either of the two C7 M/N alleles to a particular disease was found, in particular refuting the hypothesis that Lyme borreliosis may be more frequent in homozygous carriers of the hypomorphic allele C7*N.

Alleles↗
PubMed1994

Legionella pneumonia in transplant recipients: a cluster of cases of eight years' duration.

Infection with Legionella is often encountered in immunosuppressed patients, especially in recipients of renal allografts. From January 1985 until April 1993 14 cases of nosocomial legionella pneumonia were diagnosed (four by culture, 10 by serological methods) on the surgical transplantation unit of Innsbruck University Hospital. All isolates from patients and from the building's hot water were found to be Legionella pneumophila serogroup 1. They were indistinguishable from each other by monoclonal antibody subtyping and restriction fragment length polymorphism pattern and thus indicated a series of infections originating from the same source during a period of more than 8 years. Repeated efforts to control Legionella by raising the temperature in the hot water lines failed to bring permanent success. Replacing the central hot water supply with small electric water heaters installed in the patient rooms on the transplant ward now seems to have reduced the incidence of legionellosis on this unit. However, further infections occurring in transplant patients in other surgical departments in the same building indicate that a major renovation of the whole surgical building's hot water system is necessary.

Adult↗
PubMed1993

Determination of soluble CD21 as a parameter of B cell activation.

In this study we established a novel solid-phase immunoassay for CD21 using the time-resolved fluorescence of lanthanide chelates. The capture assay was able to detect concentrations of as low as 100 pg of CD21 antigen per millilitre of sample and was used for quantitative determination of CD21 in lysates of different cell lines as well as in patient serum specimens. CD21 was measured in lysates of tonsils and cell lines of B, T cell and myelomonocyte lineage, and appeared to consist of monomeric antigen under the detergent conditions used. Elevated levels of soluble CD21 were observed in serum of patients with Epstein-Barr virus (EBV) infection, a disease known to be associated with polyclonal B cell activation, and in infection with the lymphotropic rubella virus. Significantly increased levels were also found in malignancies which are associated with EBV. In patients with nasopharyngeal carcinoma (NPC), a correlation with the titre of EBV-specific IgA was observed, thus supporting a possible role of soluble CD21 as a marker for disease activity in certain malignancies. Our data suggest that measurement of soluble CD21 could serve as a marker for activation of the immune system and diseases involving the B cell lymphoid system. Possible mechanisms and functions of soluble CD21 are discussed.

B-Lymphocytes↗
PubMed1993

Isolation and biochemical characterization of the iC3b receptor of Candida albicans.

In an effort to identify the protein structure on Candida albicans, pseudohyphal forms which had been shown earlier to bind human iC3b, a protein of about 42 kDa (p42), were obtained from lysates of pseudohyphal forms by absorption with C3(H2O)-Sepharose. An antiserum raised in rabbits against this protein effectively inhibited adherence of sheep erythrocytes carrying iC3b (EAC3bi) to pseudohyphal forms. p42 cross-reacted with OKM-1, a monoclonal antibody directed against the human complement receptor type 3 (CR3, CD11b). This protein, p42, was designated p42-CR3. The antiserum against p42-CR3 was used for further purification of lysates by affinity chromatography. Three proteins of 66, 55, and 42 kDa were isolated. All were recognized by OKM-1 in immunoblots (p66-, p55-, and p42-CR3). The different proteins were separated and treated with neuraminidase and endoglycosidase F. Almost complete deglycosylation of the p66-CR3 protein was obtained after treatment with neuraminidase, indicating a high degree of glycosylation. Neuraminidase also had an effect on p55-CR3, but not on p42-CR3. Endoglycosidase F did not alter any of the three proteins. In ligand blots, p42-CR3 bound C3(H2O), C3b, and iC3b but not C3d; p55-CR3 clearly reacted with C3(H2O) and weakly reacted with C3b and iC3b. p66-CR3 never showed reactivity. It is suggested that p55 and p66 represent glycosylated forms of p42-CR3. Although C. albicans CR3 and human CR3 cross-react and bind identical ligands, the two receptors differ in structure.

Candida albicans↗
PubMed1993

[Infective pathogens as a possible etiology of idiopathic peripheral facial paralysis].

A prospective clinical study was carried out from 1988 until 1990 on 38 consecutive patients with Bell's palsy at the Neurological Department of Innsbruck University Hospital. The age range was between 16 and 88 years, the female:male ratio was 18:20. Serological methods were employed to study the impact of infectious agents on the aetiology of this disease. 11 out of 38 cases (= 29%) were probably infectious in origin, whereby 6 cases were due to Borrelia burgdorferi, 4 to Varicella zoster virus (VZV) and 1 to Herpes simplex virus (HSV), as determined by elevation of antibody titre or presence of specific IgM. Patients with a significant serological finding were treated with ceftriaxon or tetracycline for borreliosis or with acyclovir for VZV or HSV infection. Altogether, in 36 of the 38 cases a full recovery was seen at the last follow-up investigation.

Adolescent↗
PubMed1993

Early diagnosis of perinatally acquired HIV infection by the polymerase chain reaction.

31 children born to HIV-seropositive mothers were tested for the presence of HIV infection by an HIV-polymerase chain reaction (PCR) assay within the first months of life, at a time when the antibody (AB) tests did not yet allow a diagnosis. The follow-up by Western Blot and/or antigen (Ag)-ELISA indicated an HIV infection in 10 of these children. Failure to detect HIV infection by prior PCR occurred in only 1 of these patients. In this case only one sample was obtained within the first week of life and the negative PCR result may have been due to an infection of the child at delivery rather than during pregnancy. No HIV infection was detected in the remaining 21 cases, using both PCR as well as conventional methods. The simultaneously performed Ag-ELISA was clearly inferior to PCR, identifying only 4 of the 9 PCR-positive patients as early as the PCR. The perinatal HIV transmission rate in Austria was shown to be 32%, similar to that described for other European countries.

AIDS Serodiagnosis↗
PubMed1992

Polymorphism and deficiency of human factor H-related proteins p39 and p37.

We described previously cDNA clones representing a novel factor H-related 1.4 kilobase mRNA. This mRNA species codes for a doublet of serum proteins of M(r) 39,000 and 37,000 (p39/p37). The respective recombinant proteins of the three clones H-69, pFH1.4a, and pFH1.4b differ in the expression of the epitope recognized by the monoclonal antibody (mAb) 3D11. This probably reflects the difference of three amino acid residues of the deduced protein sequence. Here we report evidence for corresponding alterations in the native proteins p39/p37 in human sera. Employing mAb 3D11 and a polyclonal factor H-specific antiserum we detected three different patterns in western blot analyses of human sera which we provisionally termed FH1.4p+m+, FH1.4p+m-, and FH1.4p-m-. In the first pattern, p39/p37 were recognized by both antibodies, while in the second pattern the two proteins reacted only with the polyclonal antiserum. Both antibodies failed to detect p39/p37 in the third pattern. These phenotypes are found in the healthy population with frequencies of 0.556, 0.40, and 0.044, respectively. The frequencies of the alleles FH1.4*p+m+, FH1.4*p+m-, and FH1.4*p-m- were estimated to be 0.33, 0.46, and 0.21, respectively, assuming the gene distribution to be in Hardy-Weinberg equilibrium. Studies of 98 members from 27 families revealed an autosomal Mendelian inheritance. Southern blot data support our assumption of a polymorphism of the factor H-related proteins p39 and p37.

Blood Proteins↗
PubMed1992

Recombinant versus plasma-derived hepatitis B vaccine: comparison of immunogenicity in medical students.

A group of 92 medical students were immunized with a commercial recombinant hepatitis B vaccine (Engerix B). Antibody responses were determined and compared with those to plasma-derived Pasteur vaccine, obtained in 1986. Antibody concentrations were significantly higher in the group given recombinant vaccine, therefore this vaccine has superior immunogenicity and probably confers extended duration of protection.

Adult↗
PubMedDate not supplied

Hepatitis A in Western Austria--the epidemiological situation before the introduction of active immunisation.

Several European countries report a decreasing prevalence of antibodies to hepatitis A virus (anti-HAV). This trend is most pronounced in the youngest age groups. In 1979, however, 58% of young Austrians aged 20 to 30 years were shown to possess anti-HAV. Here we describe the current epidemiological situation in western Austria. Prevalence of anti-HAV has decreased to 7% in those 18 to 30 years old. This percentage rises to 20% (31 to 40 years of age) and 57% (41 to 50 years of age) and is highest in those older than 50 years (87%). Of 180 cases of clinical hepatitis A occurring from 1985 to 1992 45% were imported by travel to HAV-endemic areas. Seventy-one percent of the cases in children (59/83) occurred in foreign workers' families and were also predominantly acquired abroad. A change in prevention policy should be considered in this respect, as vaccination is available now.

Adolescent↗