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J Brock

Publications and source records attributed to J Brock.

At least 145 records · Page 8Linked to original sources
PubMed1981

[Defects in cell-mediated and humoral immunity in tumor-bearing mice. Evidence and characterization of suppressor cells ].

The immune response of mice bearing a transplantable tumor which was induced by Benzyprene was studied. The humoral response to sheep red blood cells (hemolytic plaque assay) is increased until the day 18 after inoculation of the tumor if calculated in relation to the total number of spleen cells, but it is decreased related to 10(6) spleen cells after day 9. Because the weight of the spleen increases during this time this result suggests that the relation between antibody producing and nonproducing cells becomes smaller, despite the total number of antibody producing cells is higher. The unspecific suppression of the cell-mediated immune response in vivo was was studied by the adoptive transfer of spleen cells from tumor bearing mice and allografting of the recipients. The rejection of the grafts is delayed. The stimulation of spleen cells with PHA is smaller with cells from tumor animals than in controls. The fraction which is nonadherent on glass beads has a higher reactivity than the total population, this difference is more distinct in tumor animals. The suppressor cells from tumor mice are glass adherent and their activity is negatively influenced by treatment of the tumor mice with Carageenan.

Animals↗
PubMed1981

[Adenosine deaminase activity and immune dysfunction (author's transl)].

Deficiency of adenosine deaminase (ADA) in lymphocytes seems to be responsible for severe combined immunodeficiency (SCID), a syndrome in early infancy untreated resulting in death. The highest amounts of ADA activity are found in lymphoid tissues. Considerable enzyme deficiency is associated with an inhibition of proliferation and differentiation, especially of the T lymphocytes, and gives rise primarily to disordered cellular immunity. The molecular mechanisms of the relationship between enzyme deficiency and immune dysfunction are widely unknown. Several possibilities are discussed. Deoxyadenosine and its nucleotides seem to be the toxic agents. The enzyme deficiency is thought to result from a mutation at the structural locus of ADA inherited in an autosomal recessive mode. In addition to transplantation of bone marrow, fetal liver, or thymus the "enzyme replacement" has been suggested for therapy of SCID in ADA deficiency, i.e. transfusion of irradiated erythrocytes with normal ADA activity.

Adenosine Deaminase↗
PubMed1981

The fate of temperature-sensitive salmonella mutants in vivo in naturally resistant and susceptible mice.

The in vivo net growth rate of salmonellae in mice is faster with virulent than with attenuated strains, and slower in resistant than in susceptible mice, the latter difference being controlled by a single host gene (Ity). Mice were injected intravenously (i.v.) with nonreplicating temperature-sensitive (TS) salmonellae mutants: TS mutants from virulent parents survived better in the RES than those from attenuated or non-virulent parents as if the latter were more susceptible to bactericidal mechanisms. However, a TS mutant from a virulent parent (Salmonella typhimurium C5) did not consistently survive better in susceptible C5) did not consistently survive better in susceptible Itys than in resistant Ityr mice, suggesting that this gene may not operate by a bactericidal mechanism. In many animals the TS salmonellae caused septic arthritis which first appeared at 2--3 weeks. Subcutaneous inoculation in the tail caused local lesions and the organism spread to the RES, but did not cause arthritis in the short term.

Animals↗
PubMed1981

Acquired immunity to Salmonella typhimurium and delayed (footpad) hypersensitivity in BALB/c mice.

BALB/c mice are extremely susceptible to salmonella infections. Previous reports have suggested that this natural susceptibility is due to a defect in cell-mediated immunity (CMI) which correlates with their inability to develop a delayed (footpad) hypersensitivity reaction to a salmonella extract when immunized with attenuated salmonellae. We have shown that mice thus immunized are in fact highly resistant to superinfecting intravenous challenge with virulent organisms, at a time when the footpad test is still negative. The footpad test becomes positive 2-3 weeks later, after the appearance of CMI, which is already present at 1 week as measured by determining the fate of a superinfecting challenge in the RES. The positive footpad reactions that develop in BALB/c mice--and also in B10, and CBA and (B10XA/J)F1 mice--are transferable to normal recipients by thetasensitive spleen cells. However, although B10 mice give positive delayed hypersensitivity (DH) reactions, they are more susceptible to salmonellae of intermediate virulence than the DH negative BALB/c strain. We have also shown that previous reports which suggested that susceptible mice did not develop immunity when vaccinated with live organisms are probably due to the salmonella strain used for vaccination, which does not establish a carrier state. A strain which does establish a carrier state effectively immunizes the susceptible BALB/c strain against virulent challenge, indicating that natural susceptibility does not preclude the development of acquired immunity to reinfection. X

Animals↗
PubMed1980

Retroperitoneal fibrosis and aortic aneurysm.

A case of bilateral ureteral obstruction associated with an abdominal aortic aneurysm is presented. The increasing frequency of this association suggests investigation of the upper urinary tract in patients with an abdominal aortic aneurysm and abdominal ultrasound in patients with bilateral ureteral obstruction.

Aged↗
PubMed1980

[Cytotoxic lymphocytes after allostimulation in vivo: kinetic, reproducibility and specificity after primary stimulation (author's transl)].

After allogeneic skin grafting and allogeneic sensibilization with spleen cells in the mouse system cytotoxic lymphocytes are induced, which can be shown in an vitro assay. The maximum of the cytotoxicity appears 2 to 3 days after transplantation. Cytotoxicity during graft rejection is clearly lower than the maximum cytotoxicity. After 3 to 4 weeks no cytotoxic lymphocytes can be detected. A similar time course is seen after sensibilization with allogeneic spleen cells. The cytotoxic lymphocytes do not react only against the stimulator haplotype if tumor cells are used as target cells. Common specificities between the stimulator and target cells may be responsible for this cytotoxicity. On the other side we found a specific cytotoxic reaction with thymocytes as target cells and in vivo no cross reaction for a second-set graft rejection.

Animals↗
PubMed1979

A model for deposition of stable and unstable aerosols in the human respiratory tract.

A model has been developed for deposition of stable and unstable aerosols in the human respiratory tract. This model has the advantages of employing a realistic asymmetric lung model and utilizing actual breath curves. Results from the model are presented for normal and abnormal breath patterns for both stable and unstable particles. Insofar as comparison is possible, agreement between model calculations and experiment appears to be reasonable.

Aerosols↗
PubMed1979

Cell mediated immune (CMI) responsiveness to soluble egg antigen (SEA) and its relation to the occurrence of schistosomal hepatosplenic disease in patients with schistosomiasis mansoni.

The delayed intradermal test and migration inhibition tests were used to assess the delayed hypersensitivity in patients with BHF and simple intestinal bilharziasis using SEA. All bilharzial patients gave a positive intradermal test. The specificity of the intradermal test using SEA is demonstrated clearly by the negative response in all control groups.

Adult↗
PubMed1978

[Absorption of anti-placenta serum by means of immunosorbents].

An anti-placenta serum was absorbed by means of immunosorbents to remove antibodies against human serum proteins. The absorption met with some difficulties, because the anti-placenta serum contained antibodies against several human serum proteins. 12 different methods were compared for their suitability to adsorb these antibodies against human serum proteins. Most suitable is human serum cross-linked by glutardialdehyde. Good results were obtained too with human serum linked to Enzacryl, Polyaminostyrene or CNBr-activated Sephadex.

Female↗
PubMed1978

[Analysis of trends in the immunologic supervision of organ transplantation].

Immunological methods of the rejection diagnostics are discussed. The humoral as well as cullular immune response against the graft is taken in consideration. The tests described up to now in literature are not suited or must still be confirmed, respectively. Thus the aptitude of the nucleolar test, of the leucocyte aggregation test, of the MLC-MEM and the rosette inhibition test for the rejection diagnostics should be increasedly examined. The immunological rejection diagnostics is complicated by the immunosuppressive therapy.

Graft Rejection↗
PubMed1978

[Immunologic course of kidney transplants studied by means of cellular and humoral immunity tests].

In 10 human-allo-transplanted persons and evaluation of the postoperative course was done with the help of specific and unspecific, cellular and humoral immune tests which were compared with clinical parameters. While the E-rosette-test did not show any correlation to the typical courses in the immunoglobulins postoperatively after a clear decrease at the time of the clinically diagnosed first set reaction an increase above all of the IgM could be observed. Unspecific tests, such as CRP and FSP may, concerning the rejection diagnostics, confirm the suspicion in as far as other factors, such as infection of the urinary tract were excluded. By choice of a suitable relation system the evidence of the immunoglobulins could possibly be proved, whereas for the cellular demonstration methods the E-rosette test does not seem to be recommendable in the performed way.

Adolescent↗
PubMed1978

[Immunoglobulins (IgG, secretory-IgA) and function of parotid gland in children with cystic fibrosis, with bronchial asthma, and with chronic bronchitis (author's transl)].

The immunoglobulins IgG and IgA (Secretory-IgA) were determined in connection with the parameters of secretion in parotid saliva. Children with cystic fibrosis, with bronchial asthma and with chronic bronchitis were compared. No significant differences were found for the groups of cystic fibrosis, of bronchial asthma, and of chronic bronchitis in comparison to a control group in relation to flow rate and protein content in parotid saliva. The comparison of the groups of diseases showed striking differences only with regard to the output of the gland after stimulation. The output of the gland per minute for IgG was decreased for patients with bronchial asthma as well as for patients with cystic fibrosis. No differences were found for the patients with chronic bronchitis and for the control group. Also the output of the gland for secretory-IgA was decreased after stimulation in the groups of disease: bronchial asthma and cystic fibrosis. The concentration of immunoglobulins in serum no correlation with the concentration of immunoglobulins in saliva neither for IgA nor for IgG. A high content of IgG in serum of patients with cystic fibrosis was observed. The mean values of IgA in serum of patients with chronic bronchitis were found to be significantly decreased.

Adolescent↗
PubMed1977

[Secretory immunoglobulin A].

Secretory IgA is the prevailung immunoglobulin on the mucous membranes of different tissues. It is a polymer immunoglobulin and in comparison to the serum IgA the secretory IgA has a additional polypeptide chain, the secretory component. The secretory IgA is synthesized locally in the mucosa. Secretory IgA is a very important factor in the immune defence of the mucous membranes. Secretory antibodies are regulated independently from serum antibodies. They show a virus neutralizing effect and activities against bacteria and lifeless noxa. The mechanism is not yet clear. It is possible, that the reaction of the secretory IgA with the antigen prevents settlement of microorganisms on the mucous membranes. The clinical importance of secretory IgA is undoubted especially the deference of the mucosa in cases of a virus infection.

Antibodies↗
PubMed1977

[Quantitative immunochemical determination of human secretory IgA].

Secretory IgA from human colostrum was fragmented by mercaptoethanol. The heavy chain fraction was prepared by means of gel chromatography on Sephadex G 100 in 1 N acetic acid. After immunization of rabbits with this heavy chain fraction the resulting antiserum contained antibodies specific for the alpha-chain and antibodies against the secretory component. These antibodies were separated by means of immunosorption. The antibodies against the secretory component precipitate free secretory component as well as bound secretory component. The antiserum is suitable for quantitative determination of secretory IgA, but free secretory component reacts too. Also secretory IgM may react, because secretory IgM contains up to 70% secretory component.

Antibodies↗
PubMed1975

[Immunological studies on the pancreas].

From 1969 to 1974 on 38 diabetic patients with terminal renal insufficiency 1,500 haemodialyses were carried out. Out of them 21 were or are in the prolonged programme of dialysis. The average duration of diabetes up to the terminal renal insufficiency was 20 years. The survival time under dialysis between 50 to 616 days was on the average nearly 248 days. The waste of substances normally contained in the urine and the normalisation of changes of minerals under dialysis is to be compared with that one in non-diabetics. The conduction of the diabetic metabolism in advanced diabetic nephropathy is independent on the form of therapy chosen difficult and undergoes strong variations. For this practical recommendations are given. Dependent on the beginning of the dialysis in 8 cases we succeeded in a temporarily limited full rehabilitation, 5 patients were partially rehabilitated and in 8 patients the general condition could be improved by the treatment without successful rehabilitation. The main complications, which were also dominating causes of death, were seen from the side of the system of coronary circulation. Mediascleroses of the arterial walls partly of a high degree allow the supposition that in these cases additionally a secondary hyperparathyroidism was in question.

Animals↗
PubMed1975

[Cellular immunity to donor antigens after kidney transplants in humans].

Decisive for controlling renal transplantation is the knowledge of the immunological reactions. The cellular immuno-mechanisms, released via sensibilization by donor HL-A antigens, are specially important for acute rejection. To predict a crisis of rejection and to initiate increased immuno-suppressive measures it is important to know the degree of cellular immunologic response. The sensibilization was demonstrated in the experiments by means of the MEM test, using graft antigens isolated from spleen or kidney of the donor. In all patients an increasing sensibilization against donor antigen could be proved. The velocity of this sensibilization seems of value for predicting the duration of the graft's survival.

Electrophoresis↗