PubMed Health⌕ Search

Biomedical subjects

O Thraenhart

Publications and source records attributed to O Thraenhart.

At least 19 recordsLinked to original sources
PubMed1992

Enumeration of T, B and natural killer peripheral blood cells of patients with multiple sclerosis and controls.

The median percentages of peripheral blood immunoglobulin-positive (Ig+) lymphocytes (8%, n = 46), CD8+ (12%, n = 49) and CD57+ cell numbers (5%, n = 37) of patients suffering from multiple sclerosis (MS) were significantly (p less than 0.05) lower than the values of age- and sex-matched healthy individuals (Ig+ cells: 13%, n = 46; CD8+ cells: 17%, n = 49; CD57+ cells: 9%, n = 37). Comparison of calculations on decreased peripheral blood cell counts and increased brain cell counts in MS patients revealed that sequestration of blood cells into the MS brain is a possible explanation of these findings.

Adult↗
PubMed1991

Alterations of the immune system following splenectomy in childhood.

After splenectomy due to blunt abdominal trauma, splenectomized children showed a restricted pattern of T-cell immunodeficiency compared to age and sex-matched normal children. Peripheral blood total (CD3) T-cell counts of 11 splenectomized children of 43%, double positive helper (CD4) inducer subpopulation (CD29) cell counts of nine splenectomized children of 7%, and phytohemagglutinin (PHA)-induced T-cell proliferation of 11 splenectomized children of 53,206 c.p.m. were significantly (p less than 0.05) lower than values of normal children (61% CD3 cells, n = 12; 13% CD4CD29 cells, n = 11; 107,832 c.p.m. PHA-induced proliferation, n = 12). The deficit of CD4CD29 cell numbers may be due to impaired maturation of these particular CD4 lymphocytes and may explain diminished PHA-induced proliferation in small children. The significantly higher B-lymphocyte counts of splenectomized children (21%, n = 11; 558 cells/mm3, n = 10) compared with 12 normal children (14%; 329 cells/mm3) may be due to loss of the reservoir function of the spleen.

Adolescent↗
PubMed1990

[Experiences with transfusion of CMV tested blood preparations after bone marrow transplantation].

Cytomegalovirus infections are frequent and often life-threatening in bone marrow transplant recipients. Among 112 of our patients after bone marrow transplantation (BMT), 28 developed clinical symptoms or laboratory test results of CMV infection, and 15 of them died. In our experience blood cell substitution with products from CMV negative blood donors does not completely prevent CMV infections. Other factors like disturbances of immunoreconstitution after BMT are relevant in promoting the development of CMV disease.

Antibodies, Viral↗
PubMed1989

Effect of strain differences on the potency testing of rabies vaccines in mice.

Antigenic differences between several strains of rabies virus, namely CVS, SAD and Flury (LEP) strains, were studied in cross-challenge experiments or cross-neutralization tests performed on sera of mice immunized with vaccines containing each strain. A typical wild fox virus strain was also included as challenge virus. The strain differences affected the relative potencies of the three vaccines in the European Pharmacopoeia mouse protection test for veterinary rabies vaccines, in that higher antigenic values were obtained when the vaccine strain was homologous to the challenge virus. This observation was confirmed by neutralizing antibody induction in mice.

Animals↗
PubMed1989

Standardization of an enzyme immunoassay for the in vitro potency assay of inactivated tissue culture rabies vaccines: determination of the rabies virus glycoprotein with polyclonal antisera.

A non-competitive enzyme-linked immunoassay (ELISA) has been standardized to supplement the in vivo potency test used for the quality control of inactivated tissue culture vaccines against rabies. The essentials of the ELISA were: fixation of the virus in different dilutions of vaccine on the surface of microtitre plates; testing of the reference and up to six test vaccines on one plate; incubation with polyclonal antisera to rabies virus glycoprotein containing an excess of antibody; further incubation with a species-specific anti-IgG coupled to peroxidase; a final incubation with a substrate. The incubation periods were 1 h, 1 h and 30 min both at +37 degrees C. The relative potency determinations were made graphically or by a computer using a parallel line bioassay in which the potencies of the vaccines of unknown potency were tested against the reference preparation on a single microtitre plate. Under these conditions inactivated rabies vaccines of different types (virus strains, cell substrates, inactivation and concentration procedures) were tested for potency. Furthermore, it was possible with this in vitro method to assay adjuvanted vaccines, in process samples such as tissue culture supernatants with live or inactivated rabies virus, concentrates, and vaccines undergoing thermal stability tests. The rabies glycoprotein antigen-antibody reaction was highly specific according to the results and the glycoprotein content was measured quantitatively. The potency determined by the in vitro ELISA correlated with the in vivo NIH protection potency test. The lower limit of detection of the ELISA was 0.015 IU/ml. Quantitative antigen determination was possible with both homologous and heterologous antisera to rabies virus glycoprotein when vaccines of the same virus strain were tested. When the potencies of vaccines of different virus strain specificity were calculated, it was necessary to take into account the strain-specific antigenicity. Even so vaccines of high potency were found to give a stronger reaction with a heterologous serum than did weak vaccines with a homologous antiserum. Stability tests made on inactivated tissue culture vaccines such as vaccine from the human diploid cell strain (HDCS), from purified chicken embryo cell (PCEC) or from purified Vero cell rabies vaccine (PVRV), showed high stability of the glycoprotein antigen even after four months of storage at +37 degrees C or 24 h at +56 degrees C, provided that the vaccines were stored in a lyophilized state. The antigenicity of liquid vaccines was inactivated after a few hours at +56 degrees C. For tropical areas, therefore, only lyophilized vaccines should be considered.

Adsorption↗
PubMed1985

[Cytomegalovirus hyperimmune globulin and cytomegalovirus-tested blood products--a pilot study in bone marrow graft recipients].

Nineteen bone marrow transplant recipients had cytomegalovirus prophylaxis using a commercial hyperimmune globulin. Seronegative donors were selected for blood component substitution. The incidence of seroconversion was 25%. One patient acquired fatal cytomegalovirus associated interstitial pneumonitis. The value of this combined cytomegalovirus prophylaxis in bone marrow transplant recipients in comparison to sole passive immunization is recommended to be the subject of a controlled trial.

Adolescent↗
PubMed1979

[Immunity against poliomyelitis in the German Federal Republic (author's transl)].

The immunity of the populations of several countries of the GFR against poliovirus 1, 2 and 3 was investigated in 11 laboratories. Sera of 4707 persons aged 0 to 30 years were assessed for neutralising antibodies (serum dilution 1:4) against the 3 types of poliovirus. 34.5% of the 4707 investigated sera had no neutralising antibodies at least against one type of the poliovirus, 4.7% showed no antibodies against all 3 types of the virus. Especially children aged 0 to 4 years were protected incompletely against the 3 types of poliovirus. In comparison with similar investigations of 1969 and 1972 no decisive change of immunity of the population of the GFR against poliomyelitis has occurred.

Adolescent↗
PubMed1979

[Rabies specific IgM- and IgG-antibody response in persons immunized with HDCS vaccine according to the Essen postexposure vaccination schedule (author's transl)].

A solid phase enzyme immunoassay (ELISA) was applied for the determination of rabies virus antibodies of the immunoglobulin classes G and M in sera of 10 young adults. Vaccinations were carried out with the Essen post-exposure vaccination schedule, which is recommended by the W.H.O., with the rabies HDCS vaccine with an antigen value of 1.9. From these results the rabies virus IgM/IgG-conversion was derived. Furthermore a comparison was carried out of results obtained with the ELISA, the mouse neutralization test, the complement fixation test and the hemagglutination inhibition test. Rabies virus-IgM-antibodies were detected already three days after the first vaccination. The IgM-antibody concentration increased to a maximum at the 22nd day p.v. In sera of seven of eight vaccinees rabies virus IgM-antibody was still detectable until the 90th day p.v. Rabies virus antibodies of the IgG-class were found in the serum of 1/7 vaccinees at the 7th day p.v. A steep increase of the rabies virus IgG-antibodies was observed from day 10 p.v. to a maximum between the 30th and 40th day p.v.. The titer values varied between 1:10-1:1600. The rabies virus IgM/IgG-conversion was observed after the 10th day p.v.. More than 75% of the total antirabies virus globulin fraction belonged to the IgG-class in sera of 6 of 9 vaccinees between the 22nd and 30th day of p.v.. A preponderance of the rabies virus IgM-antibodies was seen in 3 of 9 vaccinees until the 90th day p.v.. Most sensitive for the early detection of rabies virus antibodies was the IgM-ELISA followed by the IgG-ELISA, mouse-neutralization test, hemagglutination inhibition test and complement fixation test.

Adult↗
PubMed1978

Detection of antigenic variation in influenza virus neuraminidase by the ESSEN-NIT and the WHO standard procedure.

A new rapid modified micro-neuraminidase-inhibition test (ESSEN-NIT) has recently been described. This test was originally devised to facilitate large-scale screening for serum antibodies to influenza virus neuraminidase. It was shown that this test yielded results comparable to those obtained with the WHO standard procedure. Our report presents data on the comparison between the WHO method and the ESSEN-NIT with respect to their capability in detecting antigenic differences in neuraminidase of various strains of influenza A viruses belonging to the H3N2 subtype family. Two antiserums against the N2 antigens of the A/Hongkong/1/68 (X15HK) and of the A/Port Chalmers/1/73 (X42) recombinant strains were used in characterization experiments. The results obtained indicate that the ESSEN-NIT is at least as sensitive in detecting antigenic variations of neuraminidase as the WHO standard procedure. The drift of the N2 enzyme which occurred as early as 1969 and is known to continue to date, could be clearly demonstrated. Major and minor antigenic changes of neuraminidase in representative influenza isolates were equally well detected by both assays. The ESSEN-NIT offers the advantage of speed, economy, and computerized evaluation of data.

Antigens, Viral↗
PubMed1978

Comparative study on antibody determination by different methods in sera of persons vaccinated with HDCS rabies vaccine.

The comparative studies undertaken by 7 laboratories in 6 countries show that the calculation of I.U.'s did not, as anticipated, minimize but actually enhanced the variability of results of rabies antibody estimations in the sera of HDCS vaccinees. The high biological variance in the method(s) may not have been considered by individual laboratories and any neglect of fundamental biostatistical laws unfortunately diminishes the theoretical advantage of using the "International Standard (I.S.)" as a "tertium comparationis". Perhaps the intrinsic variability of the I.S. should be re-evaluated and it is conceivable that a pure IgG fraction of rabies antiserum would show less variability. Intralaboratory variation might be reduced by agreeing that only a geometric mean of the I.S., and not a single value obtained in an individual test, should be used for calculation of I.U.'s. Application of the principles of biochemical and pharmacological methods, such as test-to-test control of the I.S. and its analytical variances might well enhance the reproducibility of the results. MNT, RFFIT, PRT and CFT were unable to detect antibodies in HDCS vaccinees until 7 days after the first vaccination. The establishment of methods for detecting early antibody requires further investigation.

Analysis of Variance↗
PubMed1978

Some experiences with human diploid cell strain-(HDCS) rabies vaccine in pre- and post-exposure vaccinated humans.

HDCS vaccine has been in official use in the F.R.G. for pre- and post-exposure vaccination of man, after having shown its superiority to the Hempt and duck embryo vaccine--as far as compatibility, antigenicity and protective capacity is concerned--since February 1977. HDCS vaccines of both manufacturers, Mérieux/Lyon and Behring/Marburg, did not produce any severe side effects in about 5000 vaccinees in West Germany when conditions of vaccine production were properly observed. The lack of neuropathogenicity of vaccines is stressed. Contamination by bacterial lipopolysaccharides, however, resulted in endotoxin shock in 32 out of 35 vaccinees with one vaccine lot. Testing for pyrogenicity of every vaccine lot should be carefully observed in future. When comparing antigenicity of different vaccine lots of both manufacturers, individual titers of complement-fixing and neutralizing antibodies were correlated with the antigenic values of the vaccines. Duration of immunity after one course of vaccination is approximately 2 years and can be extended by only 1 booster injection for an additional 3 years. Protective capacity of HDCS vaccine (using Essen scheme, 6 applications) seems to be very pronounced. So far, between 1973-1977, 68 individuals under severe risk were vaccinated post-exposure in West Germany and 45 individuals in Iran from 1975-76. No cases of rabies occurred in the vaccinees. HDCS vaccine in man induces a very early antibody response with appearance of IgM rabies specific antibodies on day 3, and IgG rabies specific antibodies on day 7 and an early IgM/IgG antibody conversion at that time.

Antibody Formation↗
PubMed1978

Comparative study on antibody determination by different methods in sera of persons vaccinated with HDCS-vaccine.

The comparative studies undertaken by 7 laboratories in 6 countries show that the calculation I.U.s did not as anticipated minimize but actually enhanced the variability of results of Rabies antibody estaminations in the sera of HDCS vaccines. The high biological variance in the method(s) may not have been considered by individual laboratories and any neglect of fundamental biostatistical laws, unfortunately, diminishes the theoretical advantage of using the "International Standard (I.S.)" as a "tertium comparationis". Perhaps the intrinsic variability of the I.S. should be re-evaluated and it is conceivable that a pure IgG fraction of Rabies antiserum would show less variability. Intralaboratory variation might be reduced by agreeing that only a geometric mean of the I.S., and not a single value obtained in an individual test, should be used for calculation of I.U.s. Application of the principles of biochemical and pharmacological methods, such as test-to-test control of the I.S. and its analytical variances might well enhance the reproducibility of the results. MNT, RFFIT, PRT and CFT were unable to detect antibodies in HDCS vaccinees until 7 days after the first vaccination. The establishment of methods for detecting early antibody requires further investigation.

Antibodies, Viral↗
PubMed1977

[Permeability of dialysis membranes for hepatitis-B virus: on the prophylaxis of hepatitis in a haemodialysis centre (author's transl)].

Dialysis fluids of two hepatitis-Bs (HBs) antigen-positive dialysis patients were tested for hepatitis-B virus. Total dialysate volume of 5.5 litres each - as obtained on haemodialysis with the Redy-recirculation system - was concentrated by ultrafiltration and trap and rate-zonal ultracentrifugation, followed by fractionation, and purified. Electron-microscopic evidence of permeability of an intact dialysis membrane for hepatitis-B was obtained. Concentration of hepatitis-B virus was at least 10(3) to 10(4) particles per total volume. Because of the potential infectiousness of the dialysis apparatus by effective heat sterilisation after every dialysis is essential.

Adolescent↗