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J Gerdes

Publications and source records attributed to J Gerdes.

At least 109 records · Page 6Linked to original sources

Isolation of normal human follicular dendritic cells and CD4-independent in vitro infection by human immunodeficiency virus (HIV-1).

Immunohistological and electron microscopy studies of lymph nodes from patients infected with the human immunodeficiency virus 1 (HIV-1) demonstrated that follicular dendritic cells (FDC), the antigen-presenting cells of the B cell system, contain and may produce the virus. To elucidate the mode of infection of FDC with HIV-1 in vitro we developed an improved method for the preparation of single-cell suspensions of viable FDC with high purity (greater than 90% FDC). These isolated FDC were subjected to human T cell leukemia virus IIIB infection, which was monitored after 4 days in culture using the polymerase chain reaction. We were able to demonstrate that normal human FDC are highly susceptible to infection by HIV-1. Inhibition experiments with the monoclonal antibody OKT4a demonstrate that this infection is independent of the CD4 molecule.

Antibodies, Monoclonal↗

Ber-MAC3: new monoclonal antibody that defines human monocyte/macrophage differentiation antigen.

A new monoclonal antibody Ber-MAC3 is reported. It recognises a formol sensitive epitope of a not yet clustered monocyte/macrophage specific 140 kilodalton glycoprotein that is expressed on the cell surface and in the cytoplasm. In 30 cases of acute and chronic leukaemia, Ber-MAC3 staining was restricted to 15 myeloid leukaemias of M4 and M5 types. The tumour cells of two cases of true histiocytic malignancies were Ber-MAC3 positive, whereas those of all 280 malignancies of lymphocytic origin were negative. The latter included 52 cases of Hodgkin's disease and 41 cases of Ki-1 positive anaplastic large cell lymphomas which had previously been classified as true histiocytic lymphomas. Ber-MAC3 therefore seems to be of considerable value for selective identification of monocytes and macrophages at a certain stage of differentiation and seems to be suitable for diagnosing myelomonocytic or monocytic leukaemia and neoplasms of true histiocytic origin.

Antibodies, Monoclonal↗

Immunobiochemical and molecular biologic characterization of the cell proliferation-associated nuclear antigen that is defined by monoclonal antibody Ki-67.

The monoclonal antibody Ki-67 detects a human nuclear antigen that is present in proliferating cells, but absent in quiescent cells. The aim of this study was to characterize the Ki-67 antigen by means of immunobiochemical and molecular biology techniques. Enzymatic digestion experiments showed that this antigen is highly susceptible to protease treatment, and the antigen cannot be extracted by 0.1 normal HCl, indicating that Ki-67 antigen is a nonhistone protein. Immunoblot analysis of cell lysates with Ki-67 showed a double band with apparent molecular weights of 395 kd and 345 kd, regardless of whether the gels were run under reducing or nonreducing conditions. It is noteworthy that these bands were exclusively detectable in lysates prepared from proliferating cells, whereas they were absent in lysates obtained from quiescent cells. These immunobiochemical data are further substantiated by our molecular cloning approaches. By means of immunocloning with Ki-67, the authors isolated and sequenced several cDNA fragments from lambda gt11 libraries. A 1095-bp fragment gave a strong hybridization signal at 7.5 to 9.5 kb in Northern blot analysis with RNA prepared from proliferating cells, whereas it was negative with RNA prepared from quiescent cells. This cDNA fragment could be bacterially expressed, and in subsequent immunoblot analysis Ki-67 reacted exclusively with those fusion proteins that were derived from bacteria containing the insert in the right reading frame.

Antibodies, Monoclonal↗

Steroid receptors and proliferative activity in non-neoplastic and neoplastic endometria.

In the glands of cyclic endometria, proliferative activity (PA), as revealed by expression of the Ki-67 antigen, is highest in the proliferative phase (P) and early secretory phase (S1). The PA decreases in the middle secretory phase (S2). In the stroma the PA is low during the whole cycle. In P and S1, the oestrogen receptor (ER) and the progesterone receptor (PR) are strongly expressed in glands and stroma. The number of positive cells and the staining intensity decreases in S2, particularly in the glands. In atrophic endometria, fibro-glandular polyps and in endometria with arrested secretion the PA is low in both glands and stroma. ER and PR can be detected in glands and stroma. The PA in atypical hyperplasias is only slightly higher than in cyclic endometria and endometria with simple hyperplasia. The ER and PR levels are comparable to those in proliferative endometria. The PA of endometrial adenocarcinomas is positively and the ER and PR negatively correlated with the degree of de-differentiation. No ER-negative carcinoma displays the PR. Immunohistologically, non-neoplastic receptor positive tissue can be seen in many ER- and PR-negative carcinomas. These structures may falsify the biochemical receptor analysis.

Adult↗

Hodgkin's disease followed by lymphomatoid papulosis. Immunophenotypic evidence for a close relationship between lymphomatoid papulosis and Hodgkin's disease.

The clinical association of lymphomatoid papulosis and Hodgkin's disease and the striking morphologic similarity of atypical cells in lymphomatoid papulosis to Reed-Sternberg cells in Hodgkin's disease suggest that lymphomatoid papulosis and Hodgkin's disease are related. To test this possibility we studied the antigenic profile of Reed-Sternberg cells in the lymph nodes and of atypical cells in cutaneous lesions of lymphomatoid papulosis in two patients with Hodgkin's disease and lymphomatoid papulosis. In paraffin sections both cell types expressed CD30, CD45 T cell-restricted antigens, and occasionally CD15 antigens. They were negative for CD45 B cell-restricted antigens and for lysozyme. In cutaneous lymphomatoid papulosis lesions a similar immunologic profile of the atypical cells was found; that is, they were positive for CD30, CD2, CD3, and CD25 but negative for B cell and macrophage antigens. The similarity of the immunophenotype of Reed-Sternberg cells in lymph nodes affected by Hodgkin's disease and the immunophenotype of atypical cells of lymphomatoid papulosis lesions in the same patients suggests that the malignant cells in both conditions are derived from activated T cells and that they are closely related if not identical.

Adult↗

Detection of urinary TNF, IL 1, and IL 2 after local BCG immunotherapy for bladder carcinoma.

Intravesical application of bacillus Calmette-Guérin (BCG) is highly active against recurrences of superficial urothelial bladder carcinoma. In an attempt to monitor the immunological effects of this therapy, we analyzed the urine of patients following the sixth intravessical instillation, to show the presence of the monokines TNF and IL 1 and the lymphokine IL 2. Within 24 hours following the instillation, all (n = 10) patients exhibited a strong increase in urinary cytokine secretion, which was significantly different from the control group (n = 10), with respect to TNF L929 biological assay (P less than 0.01), TNF sandwich-ELISA (P less than 0.01), IL 2 CTL 6 biological assay (P less than 0.05), IL 2 sandwich-ELISA (P less than 0.005), and IL 1 sandwich-ELISA (P less than 0.05), but not to the IL 1 fibroblast biological assay. The maximum urinary secretion varied between individual patients and different cytokines, but was generally found within 2 to 8 hr after the instillation. A persistent high urinary activity was demonstrated in BCG-treated patients for IL 2 in sandwich-ELISA. These results reflect the local inflammatory response to BCG and suggest an immunomodulatory mode of action against urothelial carcinoma cells. Elucidation of the possible role of each urinary cytokine against this cancer warrants further investigations.

BCG Vaccine↗

Immunoenzymatic assessment of interferon-gamma in Hodgkin and Sternberg-Reed cells.

The typical histological picture seen in Hodgkin's disease is consistent with the release of cytokines and other active mediators by the malignant cells, i.e., Hodgkin and Sternberg-Reed cells. Since interferon-gamma is regarded as an important regulator of the cytokine cascade, we have undertaken an immunohistological assessment of this mediator in Hodgkin's disease tissue biopsies. In approximately 50% of the cases investigated we found Hodgkin and Sternberg-Reed cells to be positive with antibodies against interferon-gamma. These in situ findings were substantiated by immunostaining of Hodgkin's disease-derived cell lines L428 and L540. L540 was consistently positive, whereas L428 was negative. It is noteworthy that L428 exhibit a B-cell pheno- and genotype, whereas L540 is of T-cell origin. These data are consistent with theories that propose that cytokine production by tumour cells is central to the pathogenesis of Hodgkin's lymphoma.

Antibodies, Monoclonal↗

Effects of local bacillus Calmette-Guerin therapy in patients with bladder carcinoma on immunocompetent cells of the bladder wall.

The antitumoral effects of intravesical bacillus Calmette-Guerin against recurrent superficial urothelial bladder cancer seem to be linked to immunological effector mechanisms. To characterize further the local cellular response in the bladder wall of patients receiving intravesical bacillus Calmette-Guerin bladder biopsies were examined before and immediately after a 6-week course of bacillus Calmette-Guerin and for up to 1 year at 3-month intervals thereafter. The results showed a marked infiltration after bacillus Calmette-Guerin therapy predominantly of the suburothelial tissue with mononuclear cells, which expressed activation markers and accumulated to follicle-like granulomatous structures. With regard to T lymphocyte subsets the ratio of T helper-to-T suppressor cells in the bladder wall increased from 0.5 to nearly 2. This phenomenon persisted even in biopsies 1 year after initial treatment. In some probes activated mononuclear cells invaded the urothelium, emanating from suburothelial granulomas. It is tempting to assume that these changes within the local immunocompetent cells are related to the therapeutic effect of bacillus Calmette-Guerin against bladder cancer.

Administration, Intravesical↗

Elevations of cytokines interleukin-1, interleukin-2 and tumor necrosis factor in the urine of patients after intravesical bacillus Calmette-Guerin immunotherapy.

In an attempt to elucidate further the immunological mechanisms responsible for the effectiveness of intravesical bacillus Calmette-Guerin in the therapy of superficial urothelial bladder cancer, a prospective study was performed in which the urine of patients was examined before and after 6 intravesical instillations of bacillus Calmette-Guerin for the presence of the cytokines interleukin-1, interleukin-2 and tumor necrosis factor-alpha. Biological assays such as specific sandwich enzyme-linked immunosorbent assays were used for the analysis of each cytokine. Urinary titers of interleukin-1, interleukin-2 and tumor necrosis factor increased significantly after bacillus Calmette-Guerin instillation but showed inter-individual differences. The maximum of secretion into the urine was seen between 4 and 8 hours after the instillation, and titers returned to baseline values within 24 hours. The differences in 24-hour secretion between the bacillus Calmette-Guerin-treated (10 patients) and the control (10) groups were significant with respect to all cytokines as tested in both assays each, except for the interleukin-1 biological assay. These results reflect the strong inflammatory response in the bladder wall to bacillus Calmette-Guerin, in which the urinary secretion of the detected cytokines may be associated with the local tumor control.

BCG Vaccine↗

Proliferation, macrophage colony-stimulating factor, and macrophage colony-stimulating factor-receptor expression of alveolar macrophages in active sarcoidosis.

Alveolar macrophages (AM) in sarcoidosis display an enhanced mitotic activity. Immunocytochemical detection of the proliferation-associated Ki-67 antigen revealed significant increase in the number of proliferating AM in active sarcoidosis as compared with inactive stages of disease. Macrophage proliferation may provide an additional marker of disease activity. Since growth of macrophages is regulated by hematopoietic growth factors, we examined the expression of macrophage colony-stimulating factor (M-CSF), granulocyte M-CSF, and interleukin-3 by bronchoalveolar lavage cells in active sarcoidosis. Expression of granulocyte M-CSF or interleukin-3 genes could not be detected. AM in active sarcoidosis displayed M-CSF RNA to a comparable level like normal AM. They differed, however, in about 50% of cases analyzed, from normal AM by an enhanced level of c-fms proto-oncogene (M-CSF-receptor) expression. The enlarged proportion of proliferating AM in active sarcoidosis may be the result of an increased influx of strongly fms expressing macrophage precursors into the alveoli and autostimulation of macrophages by M-CSF.

Adult↗

Ki-67 and other proliferation markers useful for immunohistological diagnostic and prognostic evaluations in human malignancies.

The aim of this study is to briefly review proliferation markers that can be applied in immunohistochemistry, with special emphasis on the monoclonal antibody Ki-67. This antibody reacts with a nuclear antigen present in all proliferating cells which are in the active parts of the cell cycle, i.e. G1, S, G2, and mitosis, but which is absent in G0 cells. Thus, with the help of this antibody a determination of the growth fraction of a given human cell population is possible. The use of this method in human tumor diagnostics is illustrated by three examples: malignant melanoma, breast carcinoma, and malignant Non-Hodgkin lymphoma. The results show that evaluation of the growth fractions by Ki-67 is not only a diagnostic importance, but also has independent prognostic value. In addition, preliminary data on the immunobiochemical characterization of native and recombinant Ki-67 antigen are presented. In immunoblot analysis, Ki-67 detects a doublet with apparent molecular weights of greater than 300 kDa. Furthermore, our data show that cDNA clones isolated from Lambda gT11 cDNA libraries encode for parts of the Ki-67 antigen and must contain the sequence that encodes for the epitope recognized by the Ki-67 antibody.

Antibodies, Monoclonal↗

Immunohistologic assessment of cytokine production of infiltrating cells in various forms of leprosy.

The aim of this study was to determine cytokines in human leprosy lesions by means of immunohistologic examination. Cryostat sections of skin biopsies from 57 patients with various forms of leprosy were immunostained according to the APAAP method, using monoclonal antibodies against interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), and, in addition, against CD 1 antigen. Granulomas in biopsies of untreated patients with tuberculoid leprosy showed large amounts of cells positive for IL-1 beta, TNF-alpha, IFN-gamma, and CD 1, whereas no positive signals could be detected in untreated patients with lepromatous leprosy. However, in those biopsies obtained from lepromatous leprosy patients undergoing chemotherapy, positive staining for cytokines as well as subepidermal Langerhans cells increased to a detectable amount. Remarkably, in tuberculoid leprosy patients, the number of IL-1 beta--positive cells did not vary under therapy, while the number of TNF-alpha and IFN-gamma reactive cells decreased. These results suggest that immunohistologic determination of cytokines in combination with the assessment of subepidermal Langerhans cells in human leprosy lesions may be used as a parameter for the patient's status of cell-mediated immunity under chemotherapeutic treatment.

Antigens, CD↗

Relationship of cytosolic estrogen and progesterone receptor content and the growth fraction in human mammary carcinomas.

In this study of breast cancer specimens, the relationship between cytosolic estrogen (ER) and progesterone receptor (PR) content to the size of the respective growth fraction (GF) (expressed as percentage of proliferating tumor cells) was investigated. We applied the recently developed ligand-binding assay for extracts of frozen sections and Ki-67 immunocytochemistry for the assessment of the GF to adjoining serial sections of a single tissue block. If the receptor content is plotted against the percentage of Ki-67 labeled cells, an inverse relationship between receptor content and proliferation becomes obvious, meaning that a high receptor content is associated with a small GF and vice versa. If tumor specimens are grouped according to the evaluated receptor status, the mean percentage of Ki-67-positive cells is 12% for ER-positive/PR-positive (ER+/PR+), 26% for ER-positive/PR-negative (ER+/PR-), 55% for ER-negative/PR-positive (ER-/PR+), and 57% for ER-negative/PR-negative (ER-/PR-) specimens. A significant population of tumors exists, however, which exhibit a high receptor content and a high GF. The percentages of ER+/PR+ samples with a high proliferation index are 16 and 26% if the total ER+ population is considered.

Biomarkers, Tumor↗