Search PubMed⌕ Search

Biomedical subjects

H Wachter

Publications and source records attributed to H Wachter.

441 records · Page 25Linked to original sources

Evaluation on HIV serology and immune-stimulation on patients in Tanzania.

Antibodies against human immunodeficiency virus, other infectious agents and neopterin levels were determined in 253 patients in a rural area of North-West Tanzania. Seroprevalence for HIV was 3.2%. In one case serology was positive for HIV-1 and HIV-2 antibodies and questions whether there was a real double infection or a cross reaction not only concerning core region proteins but also transmembrane protein. The specificity in the diagnosis of HIV-infection is markedly increased with newer serological methods using recombinant peptides but did not improve sensitivity on African sera. Neopterin was determined as a sensitive indirect marker for the activation of T-cells and is therefore correlated with the susceptibility of HIV infection and with progression of disease. High seroprevalence rates for various infectious agents were determined and may explain the high rate of elevated neopterin levels in 80% of the Africans. Neopterin levels were even higher in HIV patients. Viral p24 antigen was found only in two persons, one of whom had no antibodies detectable.

Acquired Immunodeficiency Syndrome↗

Changes of serum neopterin, beta 2-microglobulin and interferon-gamma in patients with chronic hepatitis C treated with interferon-alpha 2b.

OBJECTIVES: Treatment with interferon (IFN) reduces viral replication and normalizes aminotransferase levels in a significant percentage of patients with non-A, non-B hepatitis or hepatitis C. Soluble immune activation markers were evaluated in patients with hepatitis. PATIENTS AND METHODS: Serum concentrations of soluble immune activation markers neopterin and beta 2-microglobulin (B2M) were compared to endogenous IFN-gamma levels in 17 patients with chronic hepatitis C before, during and after 9-months of treatment with IFN-alpha 2b. RESULTS: Before therapy some patients had increased concentrations of the studied variables. During therapy neopterin and B2M concentrations further increased whereas IFN-gamma decreased. IFN-gamma and neopterin levels were correlated before but not during therapy. The correlations between neopterin and B2M were significant throughout the study. CONCLUSION: The data indicate that IFN-gamma decreases during treatment and IFN-alpha 2b appears to enhance formation of neopterin and B2M.

Adult↗

Neopterin, a marker of cell-mediated immune activation in human pregnancy.

High neopterin excretion is closely associated with activation of cell-mediated immunity. We studied urine and serum neopterin concentrations and serum interferon-gamma concentrations in normal pregnant women. In our study population, neopterin concentrations exceeded the normal range in 663 of 840 samples (79%). Neopterin levels increased with the time of pregnancy. Serum samples drawn from women in the third trimester of pregnancy also showed high neopterin concentrations in almost all cases; however, no circulating interferon-gamma was detected. Whereas neopterin is able to penetrate into the blood stream because of its small size (M = 253 D), diffusion of interferon-gamma is limited. Raised neopterin levels provide evidence for activated cell-mediated immunity during pregnancy.

Adult↗

Serum neopterin concentrations in Wegener's granulomatosis correlate with vasculitis activity.

Raised serum neopterin concentrations were found in 13 of 27 patients (47%) with Wegener's granulomatosis. The neopterin concentrations significantly correlated with the Birmingham Vasculitis Activity Score as well as with the erythrocyte sedimentation rate and C-reactive protein. High serum neopterin levels were also associated with infectious complications. The finding of increased neopterin concentrations in patients with Wegener's granulomatosis supports the role of cell-mediated immunity and particularly of activated macrophages in the pathogenesis of the disease.

Adult↗

Cervical intraepithelial neoplasia is not associated with elevated serum neopterin levels.

Neopterin, a marker of cellular immune activation, was elevated in patients who had cervical cancer in previous studies. To examine neopterin in the presence of precursors to cervical cancer (i.e., cervical intraepithelial neoplasia) we measured serum levels in 185 colposcopy patients in Jamaica, a country with high cervical cancer incidence, and in 72 age-matched Jamaican women selected from a large population-based sample. We also measured serum levels of beta-2-microglobulin, another commonly used marker of immune activation. Neopterin and beta-2-microglobulin levels were not elevated in colposcopy patients; neither were they related to severity of cervical neoplasia. In multivariable analysis, neither adjustments for detection of cervical human papillomavirus DNA by PCR nor detection of antibodies to human T-cell lymphotropic virus type I (a retrovirus endemic to Jamaica) altered our findings. The absence of a serologically detectable increase in cellular immune activation linked to cervical intraepithelial neoplasia suggests that the immunological response to cervical intraepithelial neoplasia does not involve substantial systemic cellular immune activation.

Biomarkers, Tumor↗

Amyotrophic lateral sclerosis an enigmatic disease with B-cellular and anti-retroviral immune responses.

OBJECTIVES: The most frequent sporadic adult motor neuron disease, amyotrophic lateral sclerosis, affects more men, follows no epidemiologic pattern, and was long considered a pure spinal cord disorder. It now becomes evident that the disease is characterized by spinal, cerebral and extra-neuromuscular changes including B-cellular responses and ultrastructural skin alterations. Do these parameters identify subgroups or correlate with the male preponderance of the disease? METHODS: We analyzed age at and site of onset, sex, duration of clinical disease, and human foamy retroviral seroreactivity in 47 consecutive patients with a definite diagnosis of amyotrophic lateral sclerosis. The results were compared with antivisna seroreactivity, immunoglobulin isotypes, circulating immune complexes, neopterin and beta 2-microglobulin as well as skin biopsies in respective subsets of the same 47 patients. RESULTS: Seroreactivity to recombinant human spuma retrovirus (HSRV) envelope and/or capsid protein was positive in 20/47 amyotrophic lateral sclerosis patients, and 28/30 competed with specific retroviral antibodies on maedi-visna antigen. Anti HSRV-seronegative patients had lower immunoglobulin IgG3 isotype concentrations, while HSRV-gag plus HSRV-env antibody positives demonstrated highest circulating IgG immune complexes. All 11 amyotrophic lateral sclerosis patients partially reacting to recombinant HSRV-env or HSRV-gag antigen were men, and male amyotrophic lateral sclerosis patients tended to have higher total cerebrospinal fluid protein levels. Neopterin and beta 2-microglobulin as markers of a cellular immune activation remained basically normal in serum and cerebrospinal fluid. CONCLUSION: We suggest a particular B-lymphocytic and retroviral involvement in this enigmatic, relentlessly progressing, at present untreatable and most frequent neurological system degeneration. To our opinion this situation justifies the search for novel anti-retroviral therapeutic strategies.

Adolescent↗