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Biomedical subjects

B Klein

Publications and source records attributed to B Klein.

At least 235 records · Page 13Linked to original sources
PubMed1990

The CD24 antigen discriminates between pre-B and B cells in human bone marrow.

When bone marrow (BM) lymphoid cells from 12 adult healthy donors were labeled by CD24 antibodies and analyzed by flow cytometry, two positive populations of cells were demonstrated in each sample (by a separated bimodal specific immunofluorescence). One population had intermediate CD24-Ag density (termed CD24+ cells) whereas the other had high CD24-Ag density (termed CD24(2+) cells). CD24+ cells represented 5.8 +/- 2.7% of the total lymphoid BM cells and CD24(2+) cells 5.6 +/- 2.5%. Using dual fluorescence analysis on eight samples, all CD24+ cells expressed the CD21 and CD37 mature B cell Ag and also surface IgM (sIgM), but this population lacked CD10 Ag. These cells also expressed CD19 Ag, and at a higher density than CD24(2+) cells. They were also positive for HLA-DR Ag. Conversely, CD24(2+) cells were shown to be early cells of the B cell lineage. While all the CD24(2+) cells were HLA-DR+ and CD19+, 64 +/- 16% of them expressed CD20 Ag (at a lower density than CD24+ cells), 65 +/- 21% CD10 Ag, and 22 +/- 8% were positive for cytoplasmic mu-chains (c mu). None of these cells expressed the CD21 and CD37 mature B cell Ag or sIgM. Additional experiments on four different healthy donors demonstrated that 30 +/- 9% of the CD24(2+) cells expressed the CD34 Ag and that the CD24+ cells did not express it. Thus, the CD24 Ag permits discrimination between two populations of the B cell lineage present in adult BM: 1) A CD24(2+) cell population including "pre" pre-B cells (HLA-DR+, CD19+, CD10+/-, CD20-, CD21-, CD34+, CD37-, c mu-), "intermediate" pre-B cells (HLA-DR+, CD19+, CD10+, CD20+, CD21-, CD34-, CD37-, c mu-), and "true" pre-B cells (HLA-DR+, CD19+, CD10+, CD20+, CD21-, CD34-, CD37-, c mu+). 2) A CD24+ cell population including B cells of the standard phenotype (HLA-DR+, CD19+, CD10-, CD20+, CD21+, CD34-, CD37+, c mu-, sIgM+).

Adult↗
PubMed1990

Abnormal behavior of protein kinase C in the human myeloma cell line, RPMI 8226.

Protein kinase C activity of the human myeloma cell line, RPMI 8226, was studied after prepurification on DEAE-cellulose. The total protein kinase activity, eluted at 0.12 M NaCl, was 493 nmol/min/10(10) cells, but 38% was associated with membranes. The lipid dependence of cytosolic and membrane activities was only 52% and 21%, respectively. This activity increased with time, to as much as 200% for the membrane fraction after 7 days, whereas lipid dependence and the PDBu binding properties were lost. This modified activity was not due to the extinction of a copurifying endogenous inhibitor nor to classical PKC proteolysis. TPA-treatment of these cels is accompanied by a rapid, selective and complete loss of lipid-dependent activity of the cytosol, thus benefiting co-migrating lipid independent activity, with no membrane fraction recovery or PKM formation.

Animals↗
PubMed1990

A clinical evaluation of nuclear estrogen receptors combined with cytosolic estrogen and progesterone receptors in breast cancer.

Breast cancer tissue from 95 women was simultaneously assayed for three receptors: cytosolic estrogen (CER), cytosolic progesterone (CPR), and nuclear estrogen (NER). The main objective was to determine whether the addition of NER assay to the currently accepted practice with only CER and CPR could improve the predictive capacity of receptors. Forty-two patients were studied for response to hormone therapy and 95 patients were studied for survival; the median follow-up period was 73 months (range, 8 to 300 months). The incidence of CER+, CPR+, and NER+ was 74%, 70%, and 52%, respectively. Each receptor appeared more frequently, although not significantly so, in higher age groups. Forty percent of tumors had all three receptors positive and 14% had all negative; the remaining tumors showed all possible combinations of receptors. Both the rate of response and survival curves among 70 patients with CER+ did not show any significant difference whether NER was positive or negative. Also, among 38 patients with CER+, CPR+, and NER+, there was no significant difference in the clinical outcome as compared to 17 patients with CER+, CPR+, and NER-. Among 25 patients with CER- the rare occurrence of NER+ in only three patients did not suggest any clinical implication. It is concluded, therefore, that on overall clinical grounds the current series does not support the addition of NER assay whenever data is available on both CER and CPR.

Age Factors↗
PubMed1990

[Sea-urchin injuries].

Sea urchins (Echinoidea) are found along the Mediterranean and especially the Red Sea coasts of Israel. The most important species are Diadema setosum on the Red Sea coast, and Paracentrus lividus on the Mediterranean. When stepped on, the brittle spines penetrate and the venom they carry causes further damage. Thus the injuries are mainly mechanical, but may be complicated by a foreign body reaction to the bits of spine, to small detached segments of their covering epithelium, and damage by the epithelial venom. Severe pain, edema, local sensory loss and sometimes suppuration ensue.

Animals↗
PubMed1990

Ocular infections associated with Eikenella corrodens.

Eikenella corrodens is a gram-negative, facultative rod-shaped anaerobe that colonizes the human mouth, nasopharynx, gut, and genitourinary tract. We treated a corneal ulcer from which E. corrodens was the primary isolate in an otherwise healthy man. We treated another patient who had recurrent bacterial endophthalmitis from which Eikenella was identified in mixed culture. Named for its ability to form pits in agar, the corroding bacillus is gaining recognition for its role in head and neck infections. Certain E. corrodens strains are mobile on moist surfaces and elaborate an endotoxin, which may destroy human tissues directly and indirectly by means of the immune system. The organism is usually resistant to aminoglycosides and penicillinase-resistant penicillins yet is susceptible to penicillin and some cephalosporins.

Adolescent↗
PubMed1990

Constitutive production of interleukin-6 and immunologic features in cardiac myxomas.

The constitutive production of interleukin-6 (IL-6), a potent hepatocyte-stimulating factor and B cell-differentiating factor, was demonstrated in 3 patients with cardiac myxomas. Tumor cells from the only patient who presented with immunologic features produced 14-23-fold higher levels of IL-6 than those from the 2 patients who lacked such features. A significant serum IL-6 level (56 pg/ml), greater than that observed in patients with active rheumatoid arthritis, was also observed only in this patient, with a subsequent return to an undetectable level after surgical removal of the tumor. This was associated with a regression of the immunologic features. This same patient was observed to have an IL-6-dependent, proliferative polyclonal plasmacytosis of the bone marrow. These observations demonstrate that an overproduction of IL-6 by cardiac myxoma cells, in association with a systemic passage of this IL-6, may be responsible for the immunologic features similar to those observed in true autoimmune diseases such as rheumatoid arthritis.

Acute-Phase Proteins↗
PubMed1990

Transformation and immortalization of diploid xeroderma pigmentosum fibroblasts.

Diploid xeroderma pigmentosum (XP) skin fibroblast strains from various XP-complementation groups (B, C, G, and H) were transformed with an origin-defective SV40 early region or with the pSV3 gpt plasmid. In the latter case, transfected cells were selected for their ability to express the dominant xgpt gene. Immortalized cell lines were obtained, from XP-complementation groups C (8CA, 3MA, and 20MA; XP3MA and XP20MA were formerly considered to belong to complementation group I), G (2BI and 3BR), and H (2CS). No immortalized cells could be isolated from complementation group B (11BE). The immortalization frequency of wild-type diploid fibroblasts and diploid cultures from XP patients was not significantly increased by cotransfection with the SV40 early region plus several selected viral and cellular oncogenes. In fact, co-transfection with some of the oncogenes caused a marked decrease of the transformation frequency. The observed immortalization occurred at a frequency of approximately 5 x 10(-8).

Cell Line, Transformed↗
PubMed1990

The expression of HLA class I antigens in germ cell testicular cancer.

The expression of HLA class I antigens in testicular germ cell tumors (TGCTs) was studied by the immunoperoxidase technique. In the normal testicle, the interstitial cells of Leydig as well as most of the germ cells were significantly stained. In typical seminoma, 75% of the tumor cells in stage I and 30% in stage II were stained. In embryonal cell carcinoma, 25% of the cases in stage I and less than 10% of those in stage II were stained. Mature teratoma was stained in most of the cases, whereas in malignant teratoma only 35% of the cases showed some staining of the tumor cells. In mixed tumors each component displayed its characteristic staining pattern. The expression of class I antigens on tumor cells is required for immune recognition and lysis of the tumor by cytotoxic T-cells. The reduced expression of class I antigens that was related to histologic characteristics and stage suggests that some testicular tumors may escape immune surveillance and become biologically more aggressive.

Dysgerminoma↗
PubMed1990

Variation of HLA-ABC surface antigen expression on adenocarcinoma of the colon in correlation with the degree of differentiation.

The expression of HLA class I antigens was tested on biopsy specimens originating from 90 patients suffering from adenocarcinoma of the colon. Three different samples were examined from each specimen: one from the tumor and the other two from the neighboring surrounding surgical margins. Twenty-seven out of 27 well-differentiated carcinomas were found highly positive for the presence of HLA class I antigens. Most of the moderately well differentiated tumors (37 out of 46) were weakly positive. None of the poorly differentiated tumors (n = 11) nor the mucin-producing tumors (n = 6) expressed HLA class I antigens. In 180 histologically normal colonic epithelia from patients suffering from adenocarcinoma of the colon (surgical edges free from tumorous tissue of the same specimens) no positive expressions were found. These results tend to suggest that class I HLA-ABC deficient, poorly differentiated tumors may possibly evade lethal immune aggression by HLA-restricted cytotoxic T cells and thus progress to overt malignancy. This negative expression may provide an explanation for the poorer prognosis observed among patients afflicted by a poorly differentiated adenocarcinoma or mucin-producing adenocarcinoma of the colon. Furthermore, these results tend to suggest that enhanced expression of HLA class I antigens on colonic epithelium could serve as a clinical laboratory indication for further examination looking for the possible emergence of neoplasm. If further verified, this may prove to serve as a predictive diagnostic tool for screening populations at risk.

Adenocarcinoma↗
PubMed1989

Limiting dilution cloning of B cells from patients with multiple myeloma: emergence of non-malignant B-cell lines.

Multiple myeloma (MM) is a B-cell malignancy characterized by the accumulation of slowly proliferating malignant plasma cells in the bone marrow (BM). Several reports have shown the existence of an abnormal B-cell compartment including proliferative idiotypic B cells (i.e., B cells bearing the same idiotypic determinants as the myeloma protein) in the BM and peripheral blood (PB) of patients with MM. In order to study whether this abnormal compartment can be grown in vitro, we cultured the PB and BM of 23 patients with MM using limiting dilution methods. Our purpose was to restrict the effect of suppressor cells and the possible overgrowth of the cultures by the more rapidly growing B cells, which occurs in bulk cultures. Spontaneously growing cells were obtained only from patients seropositive for the Epstein-Barr virus (EBV) and all the cultures were composed of B cells carrying the EBV genome. Thus, positive cultures were generated only in the presence of B cells latently infected with EBV in vivo. The mean frequency of these B cells (1 in 25,000 B cells) was as low in MM patients as in healthy donors. This low frequency indicated that malignant cells do not bear the EBV genome in vivo and that the in vivo regulation of the EBV infection is unaffected in patients with MM. No Ig-gene rearrangements, specific of the autologous myeloma cells, were found in the cell lines obtained from BM or PB. Thus, the putative malignant B cells or myeloma cells were not able to generate cell lines in vitro, either spontaneously or after endogenous infection with EBV.

Antibodies, Viral↗
PubMed1989

Spontaneous secretion of tumor necrosis factor-beta by human myeloma cell lines.

Abnormal bone remodelling in the vicinity of tumor cells is a common, early feature of multiple myeloma, characterized by excessive bone resorption which is mediated by local soluble factors called osteoclast activating factors (OAF). Since interleukin-1 (IL-1) and tumor necrosis factors (TNF) are potent, synergistic OAF produced by cells of the B-cell lineage, the authors investigated the spontaneous secretion of these cytokines by 11 human myeloma cell lines (HMCL). No HMCL secreted either IL-1, the most powerful OAF, or contra IL-1. In contrast, all of the lymphoblastoid cell lines assayed produced significant IL-1 activity. Ten of the 11 HMCL secreted a significant TNF activity. This was completely eliminated by an anti-TNF beta monoclonal antibody but not affected by an anti-TNF alpha antiserum. The data from this study suggest that TNF beta is involved in myeloma bone resorption, but not IL-1, which is, however, known as one of the most potent OAF.

Antibodies, Monoclonal↗
PubMed1989

The defect in peripheral blood B-cell activation in patients with multiple myeloma is not due to a deficiency in the production of B-cell growth and differentiation factors.

The suppression of B lymphopoiesis is a major feature of multiple myeloma (MM). In this disease, there is a striking defect in the response of peripheral blood B cells to pokeweed mitogen (PWM). Normally, B-cell activation depends on B-cell growth factors (BCGFs) and B-cell differentiation factors (BCDFs), produced by peripheral blood mononuclear cells. We therefore evaluated whether the production of these cytokines was defective in patients with MM. We have studied the production of BCGFs (using the anti-mu assay) and, particularly, interleukin-2 and interferon-gamma, two well-documented BCGFs. No defect in the production of BCGFs, interleukin-2, and interferon-gamma was found in patients with active (N = 14) or stable (N = 10) MM, compared with healthy donors (N = 13). The production of BCDFs (i.e., overall activity) was also evaluated and, more particularly, that of interleukin-6 (IL-6). This cytokine is a potent BCDF which is essential in the PWM-induced activation of B cells, acting at the terminal stages of B-cell differentiation. Again, no defect in the production of BCDFs and IL-6 was found in patients with MM. Therefore, the ability to secrete cytokines controlling the process of B-cell activation is not affected in such patients. This indicates that the profound failure of humoral immune response is not due to deficiency of peripheral blood mononuclear cells producing these factors.

B-Lymphocytes↗
PubMed1989

[Contaminating substances in 22 over-the-counter fish oil and cod liver oil preparations: cholesterol, heavy metals and vitamin A].

Fish oil capsules are increasingly used by self-medicating patients. We studied 22 commercial fish oil and menhaden oil preparations in respect to accompanying substances that could be harmful. The substances measured were: cholesterol as determined by gas liquid chromatography, heavy metals measured by atomic absorption, and vitamin A as determined by high-performance liquid chromatography (HPLC). The contents of cholesterol and heavy metals were in ranges which can be regarded as negligible; the content of vitamin A in menhaden oils, however, was found in amounts which warrant that pregnant women do not exceed the dosage as recommended by the manufacturers.

Animals↗
PubMed1989

The cloned human DNA excision repair gene ERCC-1 fails to correct xeroderma pigmentosum complementation groups A through I.

The human DNA excision repair gene ERCC-1 complements the ultraviolet light (UV) and mitomycin C (MMC) sensitivity of CHO mutants of complementation group 1. We have investigated whether ERCC-1 is the mutated gene in cell lines from xeroderma pigmentosum (XP) complementation groups A through I by analyzing the endogenous gene in XP cells and by introduction of the gene followed by repair assays. Our studies show that ERCC-1 is not deleted or grossly rearranged in representative cell lines of 9 XP groups. Furthermore, Northern blot analysis revealed correct transcription of ERCC-1 in all groups. The cloned human ERCC-1 gene was introduced into immortalized XP cells by DNA transfection (groups A, C, D, E and F). The presence of the integrated transfected sequences was verified on Southern blots and by selection for 2 dominant marker genes that flank the ERCC-1 gene on the transfected cos43-34 DNA. ERCC-1 failed to confer a normal UV survival and UV-induced unscheduled DNA synthesis (UDS) to transfected populations. In the case of the remaining XP complementation groups (B, G, H and I), nuclear microinjection was used to introduce an ERCC-1 cDNA construct driven by an SV40 promoter into primary fibroblasts. Coinjection of the SV40 large T gene and analysis of its expression served as a control for the injection. The ERCC-1 cDNA failed to induce increased levels of UDS in the microinjected fibroblasts. We infer from these experiments that ERCC-1 is not the mutated gene in the 9 XP complementation groups examined. From a similar type of experiments we conclude that ERCC-1 is not the defective gene in UV-sensitive Cockayne's syndrome cells.

Blotting, Northern↗