Biomedical subjects

J R Kalden

Publications and source records attributed to J R Kalden.

At least 19 recordsLinked to original sources

PubMed1992

Analysis of immunoglobulin variable region genes from human IgG anti-DNA hybridomas.

The molecular mechanisms leading to anti-double-stranded (ds) DNA antibody production in systemic lupus erythematosus (SLE) are poorly understood. We describe here the immunoglobulin variable region genes of six human hybridomas secreting IgG anti-dsDNA antibodies derived from three SLE patients. The monoclonal IgG anti-dsDNA antibodies have been shown to be of high affinity and no multireactivity was observed (Winkler et al., Clin. Exp. Immunol., 1991. 85: 379). The comparison of the variable region genes expressed in the hybridomas with known germ-line genes as well as with the germ-line counterparts from one patient shows that the VH and VL sequences are somatically mutated. The pattern and extent of the observed somatic mutations are suggestive for an antigen-driven selection of at least four of these B cell clones. Several VH and VL genes used by the hybridomas were found to be expressed in the natural antibody repertoire, in the restricted fetal repertoire and in B cell malignancies expressing the CD5 antigen.

Amino Acid Sequence↗

PubMed1992

MHC associations of autoantibodies against recombinant Ro and La proteins in systemic lupus erythematosus. Results of a multicenter study. SLE Study Group.

Antibodies against recombinant 52 kD-Ro, recombinant 60 kD-Ro and recombinant La protein were determined by ELISA in over 300 central European patients with systemic lupus erythematosus (SLE). A strong association with HLA-DR3 was found for antibodies against 52 kD-Ro and La, but not for recombinant 60 kD-Ro antibodies in the absence of antibodies against 52 kD-Ro or La. Ro/La negative SLE patients still showed an increased frequency of HLA-DR3 as compared to healthy controls. These results indicated that the preferential formation of Ro and La antibodies was not due to an unspecific stimulatory effect of HLA-DR3 but that the antibody response to certain defined proteins (52 kD-Ro and La) was influenced by MHC genes in SLE. Furthermore, the association of SLE with HLA-DR3 was independent of the effects of DR3 on the formation of 52 kD-Ro and La antibodies.

Antibody Specificity↗

PubMed1992

Antibodies against p24 of HIV-1 in patients with systemic lupus erythematosus?

The involvement of retroviruses in the etiopathogenesis of autoimmunity is discussed. Recently antibodies against p24 of HIV-1 were described in patients from Texas with SLE. Therefore we investigated the presence of these antibodies in our SLE collective (German caucasians and blacks from Michigan) employing ELISA and Western blot. No anti-p24 reactivity was observed in our SLE patients in Western blots, suggesting that there may be ethnological or regional differences between our patients those from Texas.

AIDS-Related Complex↗

PubMed1992

In vitro activation of peripheral mononuclear cells by zinc in HIV-infected patients and healthy controls.

Zinc is a mitogen for peripheral blood mononuclear cells (PBMC). The optimal mitogenic concentration was found to be 0.05 mmol/l (327 micrograms/dl), four times higher than physiological serum levels. Maximal proliferation was observed after 6 days. Limited dilution technique revealed a frequency of zinc reactive cells of 1:3467 (median; range 1:1628-1:6235). Cord blood mononuclear cells from four of six healthy children could be stimulated to proliferate by zinc. A normal zinc-induced proliferative response could be demonstrated in all six HIV-infected patients in the Walter-Reed-stage I, in nine of 11 patients in Walter-Reed II and in only two of five patients in Walter-Reed III. In Walter-Reed IV to VI all eight patients showed a weak response to zinc (less than 50% of the healthy day control). Decreased zinc serum levels were found in 10 of 28 patients and in one of 16 controls. There was a significant correlation of a diminished zinc-induced proliferation with lower serum levels of zinc and a reduced proportion of CD4 helper cells in HIV-1-infected men. Because of a suppression of mitogenesis by high dose of zinc an excessive intake of zinc as used by some HIV-1-infected patients can presently not be recommended. The value of zinc-induced proliferation for monitoring HIV-infected patients has still to be established.

Cells, Cultured↗

PubMed1992

The role of T cells and the effect of hydrocortisone on interleukin-4-induced IgE synthesis by non-T cells.

The role of T cells for IL-4-induced IgE synthesis by peripheral blood mononuclear cells (PBMC) was investigated. The removal of monocytes from PBMC abolished IL-4-induced IgE synthesis. When PBMC were separated into T and non-T cells, non-T cells alone were not able to secrete significant amounts of IgE in the presence of IL-4. Depending on the separation procedure, the reconstitution of non-T cells with T cells prepared by rosetting did not restore IgE secretion, whereas T cells obtained by the use of anti-CD3 antibodies could co-induce IgE formation. However, when the T cells were first irradiated, large amounts of IgE were produced, which strongly exceeded those found in unseparated PBMC cultures. IL-4-induced IgE synthesis was also obtained in co-cultures of formaldehyde-fixed T cells with non-T cells. Furthermore, not only autologous but also allogeneic T cells, which have been irradiated or fixed, could provide the costimulatory effect on IgE formation by non-T cells in the presence of IL-4. Mitogenically pre-activated T cells, however, were not able to support IgE synthesis. Hydrocortisone (HC) potentiated the IL-4-induced IgE synthesis by PBMC and enabled non-T cells to secrete IgE in the presence of IL-4. Adding both HC and T cells led to a marked synergistic effect on IL-4-induced IgE production. We conclude that monocytes are required for the induction of IgE synthesis in PBMC in addition to T cells and IL-4. Our results support the view that the T cell signal is delivered via cognate and non-cognate T/B cell membrane interaction. Furthermore, active and proliferating T cells rather suppress IgE synthesis. Finally, HC appears to be a potent alternative stimulus, which bypasses the necessity for T cells in IL-4-induced IgE formation.

B-Lymphocytes↗

PubMed1992

Major histocompatibility complex haplotypes and complement C4 alleles in systemic lupus erythematosus. Results of a multicenter study.

In a multicenter study more than 300 central European systemic lupus erythematosus (SLE) patients were examined for HLA-B, HLA-DR, and complement C4 phenotypes. For 174 SLE patients MHC haplotypes were determined by family segregation analysis, and for 155 patients C4 gene deletions were determined by TaqI restriction fragment length polymorphism. Two haplotypes, B8-C4AQ0-C4B1-DR3 and B7-C4A3-C4B1-DR2, were identified as risk factors for SLE. These findings were confirmed by applying the haplotype frequency difference (HFD) method, which uses nontransmitted haplotypes from the family study as internal controls. Furthermore, only HLA-DR2, but not DR3, B7, or B8, was significantly increased in SLE patients independently of the two risk haplotypes. C4A gene deletions, but not silent C4AQ0 alleles, were increased in SLE patients and neither C4BQ0 alleles nor C4B gene deletions were increased. The observed frequencies of homozygosity and heterozygosity for the two haplotypes and the frequencies of homozygotes for C4AQ0 and C4A deletions did not differ from the expected values, indicating that the risk for SLE is conveyed by single allele effects. In conclusion, there are two MHC-linked susceptibility factors for Caucasian SLE patients carried by the haplotypes B7-DR2 and B8-DR3. The results argue against C4Q0 alleles being the decisive factors increasing susceptibility to SLE.

Alleles↗

PubMed1992

MHC gene products and anticardiolipin antibodies in systemic lupus erythematosus results of a multicenter study. SLE Study Group.

Anticardiolipin antibodies (aCL) and HLA-DR antigens were determined in 314 central European patients with systemic lupus erythematosus (SLE). Both HLA-DR4 and DR7 were increased in aCL-positive patients, and aCL were significantly associated with DRw53. The association between DRw53 and aCL was also apparent in those 17 patients with SLE and the anticardiolipin syndrome. There was no association between aCL and HLA-DQ or C4 alleles in SLE.

Antibodies, Anticardiolipin↗

PubMed1992

[Role of cytokines and growth factors in joint destruction processes].

Cytokines and growth factors are important mediators of inflammatory reactions and play a central role in the physiologic regulation of bone and cartilage cell activities and in joint destruction. The net effects of cytokines on target tissues depend on the relative pericellular concentrations of several cytokines and their inhibitors in the inflammatory tissue. It is possible to suppress the effects of cytokines with natural or synthetic inhibitory molecules. The measurement of cytokines and their inhibitors may be useful to understand the pathogenesis and to develop new therapies for inflammatory joint diseases. In this review the following cytokines will be reviewed: interleukin 1 and its inhibitor, tumor necrosis factor alpha and its inhibitor, interleukin 6, interferon gamma, transforming growth factor beta, colony-stimulating factors, fibroblast growth factors, platelet derived growth factor and prostaglandins.

Arthritis↗

PubMed1992

Persistent depletion of CD4+ T cells and inversion of the CD4/CD8 T cell ratio induced by anti-CD4 therapy.

A 49-year-old patient with refractory rheumatoid arthritis was treated repeatedly with anti-CD4 murine monoclonal antibodies. While the first anti-CD4 treatment resulted in a marked, however transient, depletion of CD4+ cells from 1070 to a minimum of 175/microliters, a second treatment cycle resulted in a persistent decrease. Despite this marked depletion, no major clinical improvement occurred, which was in striking contrast to other patients treated in a similar way. Of interest, the administration of low doses of chlorambucil led to significant clinical benefits. Markedly reduced numbers of CD4+ cells (200-500/microliters) were observed for more than 2 years, while the numbers of CD8+ cells increased after the second treatment. No infectious episodes occurred. Discontinuation of chlorambucil did not lead to increasing amounts of CD4+ cells. In contrast to the rapid reduction of CD4+ cells from the blood stream induced by anti-CD4 infusions, there was a considerable delay until altered CD4/CD8 ratios were observed in intraarticular sites. No evidence was found for either humoral or cellular immune reactivities towards CD4+ T helper cells. Our findings suggest that in certain patients undergoing anti-CD4 therapy there may be a reduced capacity of the CD4+ T helper cell pool to regenerate.

Antibodies, Monoclonal↗

PubMed1992

Pathogenic aspects of systemic lupus erythematosus (SLE).

Antibodies against native DNA are a disease-specific marker for systemic lupus erythematosus (SLE) and in addition, there is direct evidence that these antibodies also play a major part in pathogenic mechanisms leading to systemic and organ-specific disease manifestations. The origin of anti-dsDNA antibodies is still poorly understood, especially as dsDNA per se is not immunogenic. As recently shown, evidence is now accumulating that anti-dsDNA antibodies are most likely germline-encoded and antigen-selected, as demonstrated by sequence analysis of human anti-dsDNA antibody clones from SLE patients. With regard to the possible autoantigen it is of interest that sera of SLE patients show an elevated level of nucleic acids, which at least can partly be explained by defective clearance mechanisms. The question, however, whether these nucleic acids could serve as an autoantigen triggering off anti-dsDNA antibodies has not yet been solved.

Antibodies, Anti-Idiotypic↗

PubMed1991

Alpha-lipoic acid is an effective inhibitor of human immuno-deficiency virus (HIV-1) replication.

Alpha-lipoic acid, a naturally occurring disulfide-compound that acts as a cellular coenzyme, inhibits replication of HIV-1 in cultured lymphoid T-cells. Alpha-lipoic acid was added 16 hours after infection of the T-cell lines Jurkat, SupT1 and Molt-4 with HTLV IIIB and HIV-1 Wal (a wild type HIV-1 isolate). We observed a dose dependent inhibition of HIV-1-replication in CPE (Cytopathic effect) formation, reverse transcriptase activity and plaque formation on CD4-transformed HeLa-cells. An over 90% reduction of reverse transcriptase activity could be achieved with 70 micrograms alpha-lipoic acid/ml, a complete reduction of plaque-forming units at concentrations of greater than or equal to 35 micrograms alpha-lipoic acid/ml. An augmentation of the antiviral activity was seen by combination of zidovudine and low dose of alpha-lipoic acid (7 micrograms/ml). Trypan blue staining revealed no toxic effects of alpha-lipoic acids on peripheral blood mono-nuclear cells and T-cell lines even in concentrations of greater than or equal to 70 micrograms/ml. Therefore, we propose the inclusion of alpha-lipoic acid into chemotherapy trials in combination with zidovudine.

Cells, Cultured↗

PubMed1991

Functional characterization of tumor-infiltrating lymphocytes, lymph-node lymphocytes and peripheral-blood lymphocytes from patients with breast cancer.

Mononuclear cell infiltration is frequently seen within human solid tumors. Effector cells within the tumor site usually fail to exhibit cytotoxic or natural killer activity when freshly isolated; however, they develop potent and sometimes specific cytotoxicity after expansion in IL2. Thus, local tumor environment may influence lymphocyte function. In our study, we disaggregated human breast-cancer and lymph-node tissue to obtain lymphocyte-enriched cell fractions. Besides phenotypic analysis, functional characterization with regard to proliferation and cytokine production of tumor-infiltrating lymphocytes (TIL), peripheral-blood lymphocytes (PBL) and lymph-node lymphocytes (LNL) was the aim of our study. TIL showed an enrichment of CD8+ cells with a corresponding decrease in CD4+ cells in comparison with PBL and LNL. In response to PHA, TIL showed decreased 3H-thymidine uptake, but TIL were significantly stimulated by rhIL2. TIL produced low levels of IL2, TNF and IFN gamma upon mitogen/phorbol ester stimulation, while PBL produce high levels of TNF and IFN gamma but low levels of IL2. Under the same experimental conditions, LNL produce high levels of TNF and IL2 but low levels of IFN gamma. Mitogen-mediated TNF secretion was increased after addition of autologous tumor cells in TIL and LNL, whereas IFN gamma secretion tended to be suppressed. Our results indicate different patterns of activities of TIL, LNL and PBL from breast-cancer patients.

Breast Neoplasms↗

PubMed1991

Neutrophils express the high affinity receptor for IgG (Fc gamma RI, CD64) after in vivo application of recombinant human granulocyte colony-stimulating factor.

Fc receptors are important effector molecules of neutrophilic granulocytes (polymorphonuclear neutrophils [PMN]), connecting phagocytic cells and the specific immune response. Neutrophils from healthy donors express the low-affinity receptors for IgG Fc gamma RII (CD32) and Fc gamma RIII (CD16), but not the high-affinity receptor Fc gamma RI (CD64). The latter has been found on neutrophils from patients with certain bacterial infections and can be induced in vitro after incubation with interferon-gamma. We show here that neutrophils strongly express Fc gamma RI after in vivo application of recombinant human granulocyte colony-stimulating factor (rhG-CSF). PMN from patients receiving rhG-CSF displayed higher cytotoxicity against Daudi lymphoma cells in vitro compared with control patients and with healthy donors. Fab fragments against Fc gamma RII (monoclonal antibody [MoAb] IV.3) inhibited neutrophil-mediated cytotoxicity of healthy donors but not of patients during rhG-CSF therapy. Therefore, expression of Fc receptors by PMN was investigated by flow cytometry and the mean fluorescence intensity (MFI) was compared. After staining with MoAb 32.2 against Fc gamma RL, the median MFI of neutrophils from G-CSF patients (median, 4.78; range, 2.40 to 8.50; n = 5) was significantly higher (P = .002 and P = .001, respectively) than the median MFI of patients not receiving G-CSF (median, 1.23; range, 1.01 to 1.58; n = 6) and the median MFI of healthy donors (median, 1.04; range, 0.67 to 1.12; n = 6). Fc gamma RI disappeared after the discontinuing of the G-CSF injections, but was reinduced during the next treatment cycle with rhG-CSF. The high expression of Fc gamma RI during rhG-CSF therapy correlated with enhanced cytotoxicity. In vitro incubation with rhG-CSF also enhances cytotoxicity, but only minor increments in Fc gamma RI expression were observed. Thus, during in vivo application of rhG-CSF neutrophils acquire an additional potent receptor for mediating tumor cell killing in vitro by induction of the high-affinity receptor for IgG (Fc gamma RI, CD64).

Antibodies, Monoclonal↗

PubMed1991

[Human anti-murine immunoglobulin antibodies as disturbing factors in TSH determination].

Monoclonal murine antibodies are increasingly used for immunotherapy and in vivo diagnostic procedures such as immunoscintigraphy. The therapeutic or diagnostic reagent however, is a foreign antigen, which may induce host reactivity. This may interfere with the therapeutic or diagnostic reagent in vivo, resulting in a loss of efficacy or the necessity to increase dosages. In addition, there is an important interference to in vitro immunoassays detecting specific antigens utilizing murine monoclonal antibodies. In the present study, sera of patients who had undergone a therapeutic trial using 140 mg of an anti-CD4 antibody, were investigated. Human anti-murine-immunoglobulin-antibodies (HAMA) were detected 2-3 weeks after treatment was started and reached maximal amounts of 0.8 micrograms/ml after a single and 2 micrograms/ml after a repeated treatment course. Parallely raised values of TSH were found in sera containing HAMAs of more than 0.3 micrograms/ml. Elevations of TSH levels up to 13 microU/ml were most pronounced after a repeated trial of the murine antibody and were detectable up to 20 weeks.

Antibodies, Monoclonal↗

PubMed1991

Treatment of rheumatoid arthritis with an anti-CD4 monoclonal antibody.

The effect of treatment with a monoclonal antibody against the CD4 antigen present on T helper cells was studied in 10 patients with severe intractable rheumatoid arthritis. In an open trial, monoclonal antibody 16H5 was infused at a dosage of 0.3 mg/kg of body weight on 7 consecutive days. Studies of the kinetics demonstrated a drastic depletion of CD4+ cells, to as low as 25 cells/microliters, 1 hour after the first infusion. The subsequent recovery of the CD4+ cell numbers 24 hours after infusion did not reach initial levels, and after the full 7-day treatment cycle there was a significant reduction of the number of CD4+ cells (mean +/- SD 51 +/- 28%; P less than 0.02). There was a reduced or even inverse CD4:CD8 ratio, which generally persisted 3-4 weeks. Lymphocyte transformation assays demonstrated significantly reduced reactivity in 5 of the 9 patients who completed the 7-day course, whereas 4 individuals exhibited an unexpected elevation in the T cell response to mitogens and common antigens. Parallel laboratory studies showed a significant decrease in the erythrocyte sedimentation rate (P less than 0.05), rheumatoid factor titer (P less than 0.04), and total immunoglobulin values (P less than 0.01), as well as a reduction in C-reactive protein levels, in 7 of the 9 patients. Clinically, there was a significant reduction in the Ritchie articular index (P less than 0.05) and in the number of swollen joints (P less than 0.04). Adverse effects were urticaria in 2 patients, which led to withdrawal of therapy in 1 of them, and chills with fever, suggestive of a lymphokine release syndrome, in another 2 patients. Only low levels of human anti-mouse immunoglobulin antibodies developed (not exceeding 1.7 mg/liter). It was therefore possible to repeat the treatment cycle, achieving still better efficacy, in 4 of the patients (reductions in the Ritchie index and the number of swollen joints P less than 0.02). Our findings indicate that treatment with monoclonal antibodies against the CD4 antigen leads to immunomodulation which results in clinical benefits, at least during initial observation periods (up to 6 months postinfusion). However, it remains to be determined whether long-term remission can be induced with this therapeutic approach. The use of immunosuppressive therapies or repeated antibody treatments will have to be considered.

Adult↗

PubMed1991

T cell proliferation induced by Borrelia burgdorferi in patients with Lyme borreliosis. Autologous serum required for optimum stimulation.

The cellular immune response to Borrelia burgdorferi was studied in 24 patients with seropositive and seronegative Lyme borreliosis, 30 patients with arthritides of different origin (non-Lyme arthritides), and 20 normal blood donors. By far, the strongest T cell stimulation was induced by incubation with autologous serum; there was a significantly lower response or no response after incubation with allogeneic or heterologous sera. In patients with Lyme borreliosis, including seronegative patients, there was a strikingly elevated proliferation in response to whole B burgdorferi bacteria (mean 64,750 dpm) compared with that of normal donors (mean 19,700 dpm; P less than 0.0001) and especially that of non-Lyme arthritis patients (mean 11,600 dpm; P less than 0.0001). Levels of proliferation declined significantly in patients with Lyme borreliosis after successful antibiotic treatment. Parallel cultures using B burgdorferi and Treponema phagedenis as antigens showed that cells from patients with Lyme borreliosis responded significantly more to B burgdorferi than to T phagedenis, but this did not occur with cells from individuals with non-Lyme arthritides. There was no correlation between disease stages and proliferation values. These data indicate that lymphocyte proliferation assays may provide an important tool for the diagnosis of Lyme borreliosis, most notably in patients with arthritides and in those who are seronegative. Conversely, the lack of reactivity appears to be a strong indicator of the absence of active Lyme disease. It seems to be crucial, however, to use autologous sera in these assays.

Adolescent↗

PubMed1991

Testing for association in SLE families.

Systemic lupus erythematosus (SLE) is a complex disease which is partly determined by genetic factors which influence susceptibility to the disease phenotype. In this association study we try to define the high risk haplotypes which are responsible for this disease, together with other environmental factors. In many other association studies a set of SLE patients is compared to a set of controls. The basic assumption about the underlying population is that the disease and control sample should originate from the same genetic population, which is not always completely satisfied in many studies. Therefore, we analyse our family data by applying the Haplotype Frequency Difference (HFD) Method, which constructs its internal control group from those haplotypes not transmitted to the affected individual. Results partially conform with other studies, showing that the haplotypes B8 DR3 as well as B7 DR2 have a high positive association with SLE. When the DR locus was analyzed alone, we found besides the alleles DR2 and DR3 a negative association for DR1, DR5, and DR6.

Adult↗

PubMed1991

An anti-CD4 antibody for treatment of chronic inflammatory arthritis.

Monoclonal antibodies (mAb) to the CD4 surface molecule inhibit the function of CD4+ T cells in vitro and have been used for treatment of autoimmune diseases in several animal models. Recently, an anti-CD4 mAb has been described that improved the clinical situation of rheumatoid arthritis (RA) patients although no change in laboratory parameters could be observed. Here, we report on a different high-affinity anti-CD4 mAb (MAX.16H5) and its use for treatment of RA. Reduction of the Ritchie index, morning stiffness and the number of swollen joints demonstrated the clinical benefits of the therapy. In addition, laboratory parameters like ESR, CRP, and rheumatoid factor were reduced in 6/12 treatments. A rapid depletion of CD4+ T cells was observed in all patients which reached a minimum 1 hour after administration. However, efficacy of treatment did not correlate with T cell depletion. The antibody accumulates at the site of inflamed joints as detected by 99m-Tc-labelling. Affected digital joints were detected earlier by virtue of helper T cell imaging than by conventional bone scans.

Antibodies↗