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Biomedical subjects

H Haas

Publications and source records attributed to H Haas.

At least 127 records · Page 7Linked to original sources
PubMed1990

[Quantitative determination of immunoglobulin G (IgG) subclasses].

The four IgG subclasses differ with respect to structure and biological function. Within the last 26 years, numerous immunological methods have been developed to study the role of the individual subclasses in humoral immune response. Different methods for quantitative IgG-subclass determinations are discussed with special reference to reliability and standardization. The clinical indications for measuring IgG-subclass levels are listed.

Humans↗
PubMed1990

[Immunoglobulin G subclass deficiency in patients with asthma and chronic obstructive bronchitis].

In 99 patients with asthma or chronic obstructive bronchitis immunoglobulins and immunoglobulin-G subclasses were measured to characterize the frequency of humoral immune deficiencies. 26 patients had decreased serum levels in one or two IgG subclasses. So IgG-subclass deficiency is a common finding in patients with asthma and obstructive bronchitis. Treatment with corticosteroids seems to promote low IgG-subclass levels, but cannot fully explain alterations of IgG subclasses. Today IgG-subclass deficiencies are regarded as an important factor in the susceptibility to recurrent infections. We think, variation in IgG subclasses may have further effects on the noninfectious inflammatory processes of asthma and obstructive bronchitis.

Asthma↗
PubMed1990

[Increased serum IgE concentration in lung tuberculosis].

In about one-half of patients with pulmonary tuberculosis, elevations of the IgE serum concentrations are found which, under anti-tuberculous therapy, reveal a tendency to regress. Aetiologically, in addition to an unspecific B-cell activation, a specific reaction of the immune system may be considered.

Adolescent↗
PubMed1989

Identification of a cell surface-associated protein involved in mouse neural cell aggregation by means of antibodies against the sponge aggregation factor.

Polyclonal antibodies were raised against the purified aggregation factor (AF) from the sponge Geodia cydonium to elucidate possible immunological relationships between adhesion molecules of lower multicellular eukaryotic systems (sponges) and those of vertebrates. This anti-AF recognized a series of polypeptides associated with the AF, among them also a polypeptide with a Mr of 47,000 (p47). The formation of the antibody-p47 immunocomplexes could be prevented by adsorbing the anti-AF with a brain extract from DBA/2J mice. Moreover, this brain polypeptide inhibited the AF-mediated aggregation of sponge cells. Interestingly, the anti-AF recognized a p37 molecule in the brains of 2- to 3-day-old mice; no reaction could be traced using brain extracts from animals older than 2 months. The anti-AF failed to interact with polypeptides from mouse liver or spleen. By indirect immunofluorescence staining the p37 was found to be localized on the plasma membranes of brain cells. Moreover, Fab' fragments of the anti-AF inhibited aggregation of mouse brain cells. These data indicate that the sponge anti-AF recognizes a p37 molecule in mouse brain cells which is either directly or indirectly involved in brain cell aggregation.

Animals↗
PubMed1989

[Determination of immunologic parameters in patients with lung tuberculoses of various stages with special reference to serum IgE concentration].

In patients with lung tuberculosis--depending on the severity of the disease--delayed-type hypersensitivity reaction is weakened, also in cases of non-miliary tuberculosis. On analysing the mononuclear cells of peripheral blood, abnormalities are found, in particular an increase in the monocyte count. In addition to increasing levels of serum immunoglobulin A and G, circulating immune complexes were detected in 50% of the patients. In 50% of the patients we found elevated IgE-serum levels, which decreased in response to treatment but did not return to normal.

Adolescent↗
PubMed1987

Conventional isoelectric focusing does not dissociate immune complexes.

Contrary to some reports, isoelectric focusing (IEF) is unable to dissociate immune complexes (IC) into their constituent components. Six model IC systems prepared at various antigen/antibody ratios were readily dissociated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), but not by conventional IEF, independently of several modifications of the running conditions. IC preformed in situ in the IEF gel were not disrupted by subsequent electrophoresis. Moreover, formation of IC was demonstrable in IEF, when applying antigen and antibody preparations in the manner used for counterimmune electrophoresis. Nevertheless, IEF may be of value in the analysis of IC provided the complexes are of small enough size to enter the gel.

Animals↗
PubMed1987

Homogeneous immunoglobulins in the sera of lung carcinoma patients receiving cytotoxic chemotherapy--detection with the use of isoelectric focusing and immunoblotting.

Using isoelectric focusing (IEF) with immunoblotting, we have analysed serum immunoglobulins of 15 lung cancer patients on cytotoxic chemotherapy. In five of the patients homogeneous immunoglobulins were found which appeared between 9 and 18 months after beginning of treatment and were monoclonal in two and oligoclonal in three cases. These abnormalities were only partially shown by zonal electrophoresis with immunofixation and not detected by immune electrophoresis. Examination of 10 normal and 10 myeloma sera by the three techniques in parallel confirmed the competence and sensitivity of IEF with immunoblotting in detecting homogeneous immunoglobulins. Thus, this method provides a valuable tool for investigating an abnormal regulation of the immunoglobulin synthesis.

Aged↗