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C K Goldman

Publications and source records attributed to C K Goldman.

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Flow cytometric resonance energy transfer measurements support the association of a 95-kDa peptide termed T27 with the 55-kDa Tac peptide.

Two monoclonal antibodies (OKT27 and OKT27b) have been produced that react with distinct epitopes of a 95-kDa peptide. The T27 antigen is widely distributed, being expressed on B lymphocytes, monocytes, and adult T-leukemic cells but not on polymorphonuclear leukocytes or platelets. There was a low level of T27 expression on resting T cells that increased on T-cell activation. In preliminary studies, the OKT27b antibody coprecipitated a 55-kDa peptide, as well as the 95-kDa peptide, from the radiolabeled cells of the HuT 102B2 cell line. Preclearance with anti-Tac, a monoclonal antibody to the 55-kDa peptide of the multichain interleukin 2 receptor, removed the 55-kDa but not the 95-kDa peptide from subsequent OKT27b immunoprecipitates of HuT 102B2 extracts, suggesting the possibility that the T27 peptide was associated with the Tac peptide. However, the precipitation of the p55 Tac peptide by OKT27b was quite inconsistent. Thus, additional information was sought using a flow cytometric energy transfer technique to provide a physical estimation of the proximity between the Tac and the T27 peptides. The flow cytometric version of the fluorescence resonance energy transfer technique permits the determination of inter- and intramolecular distances at 2- to 10-nm levels on a cell-by-cell basis. Using this approach, there was a mean energy transfer of 7.3% with HuT 102B2 cells when fluorescein isothiocyanate anti-Tac served as the donor and tetramethylrhodamine isothiocyanate OKT27 served as the acceptor. In contrast, there was no energy transfer in comparable studies observed when fluorescein anti-Tac and rhodamine anti-transferrin receptor antibodies were used. These observations support the conclusion that there is a close nonrandom proximity in HuT 102B2 cells between the 95-kDa peptide identified by the OKT27 monoclonal antibody and the p55 Tac peptide of the multichain interleukin 2 receptor.

Antibodies, Monoclonal↗

Demonstration of a non-Tac peptide that binds interleukin 2: a potential participant in a multichain interleukin 2 receptor complex.

The interleukin 2 (IL-2) receptor system plays a key role in the T-cell immune response. Although IL-2 binding was reported to be restricted to the Tac peptide, we have identified an IL-2 binding peptide that does not react with anti-human IL-2 receptor monoclonal antibodies, including anti-Tac on MLA 144, a gibbon ape T-cell line. The MLA 144 cell line expressed 6800 IL-2 binding sites per cell with a low (Kd = 14 nM) affinity for human recombinant IL-2. Using cross-linking methodology, we demonstrated that the IL-2 binding peptide on MLA 144 is larger (Mr 75,000) than the Tac peptide, which has a Mr of 55,000. An IL-2 binding peptide of similar size (Mr 75,000) was also identified in addition to the Tac peptide (Mr 54,000-57,000) on Hut 102, a human T-cell lymphotrophic virus I-induced T-cell leukemia line, and phytohemagglutinin-activated normal human and gibbon ape lymphoblasts. Anti-Tac antibody did not block the binding of 125I-labeled IL-2 to MLA 144 cells. However, this antibody abolished the binding of 125I-labeled IL-2 not only to the Tac peptide on Hut 102 cells and normal lymphoblasts but also to the Mr 75,000 IL-2 binding peptide, suggesting that this latter peptide is associated with the Tac peptide to form the high-affinity IL-2 receptor complex.

Animals↗

Postsynaptic alpha 2-noradrenergic receptors mediate feeding induced by paraventricular nucleus injection of norepinephrine and clonidine.

This study examines the feeding response induced by hypothalamic noradrenergic stimulation, in terms of the type and synaptic position of its mediating receptor. Tests with norepinephrine or the alpha 2 receptor agonist clonidine, injected into the area of the paraventricular nucleus (PVN), revealed a potent feeding response in satiated animals. This response by either agonist was blocked, in a dose-dependent fashion, by local injection of the alpha 2-noradrenergic antagonists, rauwolscine and yohimbine. It was also blocked by the general antagonist, phentolamine. In contrast, it was unaffected by hypothalamic injection of the alpha 1-noradrenergic antagonists, prazosin and corynanthine. These results indicate that feeding elicited by noradrenergic stimulation in the region of the PVN is mediated through alpha 2-type receptors. These alpha 2 receptors appear to be located postsynaptically, since the effectiveness of clonidine in eliciting eating was undisturbed by prior injection of the catecholamine synthesis inhibitor, alpha-methyl-p-tyrosine.

Animals↗

Interleukin 2 receptor (Tac antigen) expression in HTLV-I-associated adult T-cell leukemia.

Interleukin-2 (IL-2) is a lymphokine synthesized by some T-cells following activation. Resting T-cells do not express IL-2 receptors, but receptors are rapidly expressed on T-cells following interaction of antigens, mitogens, or monoclonal antibodies with the antigen-specific T-cell receptor complex. Using anti-Tac, a monoclonal antibody that recognizes the IL-2 receptor, the receptor has been purified and shown to be a Mr 33,000 peptide that is posttranslationally glycosylated to a Mr 55,000 mature form. Normal resting T-cells and most leukemic T-cell populations do not express IL-2 receptors; however, the leukemic cells of the 11 patients examined who had human T-cell lymphotropic virus-associated adult T-cell leukemia expressed the Tac antigen. In human T-cell lymphotropic virus-I infected cells, the Mr 42,000 long open reading frame protein encoded in part by the pX region of this virus may act as a transacting transcriptional activator that induces IL-2 receptor gene transcription, thus providing an explanation for the constant association of IL-2 receptor expression with adult T-cell lymphotropic virus-I infection of lymphoid cells. The constant expression of large numbers of IL-2 receptors which may be aberrant may play a role in the uncontrolled growth of adult T-cell leukemia cells. Two patients with Tac-positive adult T-cell leukemia have been treated with the anti-Tac. One of the patients had 6- and 3-mo remissions of his leukemia following two courses of therapy with this monoclonal antibody directed toward this growth factor receptor.

Adult↗

Expression of interleukin 2 receptors on activated human B cells.

Using anti-Tac, a monoclonal anti-interleukin 2 (IL-2) receptor antibody, we have explored the possibility that certain activated B cells display receptors for IL-2. Resting normal B cells and unselected B cell lines established from normal individuals were Tac antigen negative. In contrast, the cell surface Tac antigen expression was demonstrable on 6 of 10 B cell lines from patients with Burkitt's lymphoma, 5 of 6 B cell lines derived from patients with HTLV-I-associated adult T cell leukemia (including all four that had integrated HTLV-I into their genome), and on certain normal B cells activated with pokeweed mitogen. Furthermore, cloned Epstein-Barr virus-transformed B cell lines derived from Tac-positive normal B cells continued to express the Tac antigen in long-term cultures and manifested high affinity IL-2 receptors identified in binding studies with purified radiolabeled IL-2. The line 5B4 developed in the present study could be induced with purified JURKAT-derived or recombinant IL-2 to express a larger number of IL-2 receptors. Furthermore, the addition of IL-2 to the 5B4 B cell line augmented IgM synthesis, which could be blocked by the addition of anti-Tac. The size of the IL-2 receptors expressed on the cloned normal B cell lines was similar (53,000-57,000 daltons) to that of receptors on phytohemagglutinin-stimulated T cell lymphoblasts. Thus, certain malignant and activated normal B cells display the Tac antigen and manifest high affinity receptors for IL-2. These data suggest that IL-2 may play a role in the differentiation of activated B cells into immunoglobulin-synthesizing and -secreting cells.

Antibodies, Monoclonal↗

Functional and phenotypic comparison of human T cell leukemia/lymphoma virus positive adult T cell leukemia with human T cell leukemia/lymphoma virus negative Sézary leukemia, and their distinction using anti-Tac. Monoclonal antibody identifying the human receptor for T cell growth factor.

Adult T cell leukemia (ATL) and Sézary leukemia are malignant proliferations of T lymphocytes that share similar cell morphology and clinical features. ATL is associated with HTLV (human T cell leukemia/lymphoma virus), a unique human type C retrovirus, whereas most patients with the Sézary syndrome do not have antibodies to this virus. Leukemic cells of both groups were of the T3, T4-positive, T8-negative phenotype. Despite the similar phenotype, HTLV-negative Sézary leukemic cells frequently functioned as helper cells, whereas some HTLV-positive ATL and HTLV-positive Sézary cells appeared to function as suppressors of immunoglobulin synthesis. One can distinguish the HTLV-positive from the HTLV-negative leukemias using a monoclonal antibody (anti-Tac) that appears to identify the human receptor for T cell growth factor (TCGF). Resting normal T cells and most HTLV-negative Sézary cells were Tac-negative, whereas all ATL cell populations were Tac-positive. The observation that ATL cells manifest TCGF receptors suggests the possibility that an abnormality of the TCGF-TCGF receptor system may partially explain the uncontrolled growth of these cells.

Adult↗

Interleukin-2 receptor expression in retrovirus associated adult T-cell leukemia.

Interleukin-2 (IL-2) is a lymphokine synthesized by some T cells following activation. Resting T cells do not express IL-2 receptors but receptors are rapidly expressed on T cells following the interaction of antigens, mitogens, or monoclonal antibodies with the antigen specific T-cell receptor complex. Using anti-Tac a monoclonal antibody that recognizes the IL-2 receptor, the receptor has been purified. The receptor is a 33 kdalton peptide that is post-translationally glycosylated to a 55 kdalton mature form. Mature receptors contain both N-linked and O-linked sugars and are both sulfated and phosphorylated. Using an oligonucleotide probe, based on the N-terminal amino acid sequence, cDNAs encoding this receptor have been cloned, sequenced and expressed. The addition of anti-Tac to in vitro culture systems blocks the IL-2 induced DNA synthesis of IL-2 dependent T-cell lines and inhibits soluble auto- and alloantigen induced T-cell proliferation. Furthermore, it prevents the generation of cytotoxic and suppressor effector T cells. The anti-receptor antibody also inhibits lectin stimulated immunoglobulin synthesis and the sequential expression of late appearing activation antigens on T cells. Normal resting T cells and most leukemic T-cell populations do not express IL-2 receptors however the leukemic cells of all patients with human T-cell leukemia/lymphoma virus (HTLV-I) associated, adult T-cell leukemia (ATL) examined expressed the Tac antigen. In HTLV-I infected cells the 42 kdalton long open reading frame (LOR) protein encoded in part, by the pX region of HTLV-I may act as a transacting transcriptional activator that induces transcription of the IL-2 receptor gene thus providing an explanation for the constant association of HTLV-I infection of lymphoid cells and IL-2 receptor expression. The constant display of large numbers of IL-2 receptors which may be aberrant in the ATL cells may play a role in the uncontrolled growth of these leukemic T cells. Patients with the Tac positive ATL are being treated with an anti-Tac monoclonal antibody directed towards this growth factor receptor.

Antibodies, Monoclonal↗

Disorders of B cells and helper T cells in the pathogenesis of the immunoglobulin deficiency of patients with ataxia telangiectasia.

The pathogenesis of the immunoglobulin deficiency of 20 patients with ataxia telangiectasia was studied using an in vitro immunoglobulin biosynthesis system. 10 patients had no detectable IgA in their serum as assessed by radial diffusion in agar and 3 had a reduced serum IgA concentration. The peripheral blood mononuclear cells of 17 of the patients and 17 normal controls were cultured with pokeweed mitogen for 12 d and the immunoglobulin in the supernatants measured. The immunoglobulin synthesis was below the lower limit of the normal 95% confidence interval for IgM in 5 patients, for IgG in 8, and for IgA in 14. The mononuclear cells from 9 of the 10 patients with a serum IgA concentration less than 0.1 mg/ml failed to synthesize IgA in vitro. None of the patients manifested excessive suppressor cell activity. All patients had reduced but measurable helper T cell activity for immunoglobulin synthesis by co-cultured normal pokeweed mitogen-stimulated B cells (geometric mean 22% of normal). Furthermore, the addition of normal irradiated T cells to patient peripheral blood mononuclear cells led to an augmentation of IgM synthesis in 15 of 17 and to increased IgG synthesis in 9 of the 17 patients studied, including 9 of the 12 patients who had synthesized IgG before the addition of the irradiated T cells. In addition, IgA synthesis was increased in all eight patients examined that had serum IgA concentrations greater than 0.1 mg/ml. These studies suggest that a helper T cell defect contributes to the diminished immunoglobulin synthesis. However, a helper T cell defect does not appear to be the sole cause since there was no IgA synthesis by the peripheral blood mononuclear cells of 9 of the 10 patients with a profoundly reduced serum IgA even when co-cultured with normal T cells. Furthermore, the cells of the nine patients with profoundly reduced IgA levels examined also failed to produce IgA when stimulated with the relatively helper T cell-independent polyclonal activators, Nocardia water soluble mitogen or Epstein-Barr virus. Taken together these data support the view that the reduced immunoglobulin synthesis of these patients is due to defects of both B cells and helper T cells. Such a broad defect in lymphocyte maturation taken in conjunction with our demonstration of persistent alpha fetoprotein production by ataxia telangiectasia patients provides support for the proposal that these patients exhibit a generalized defect in tissue differentiation.

Ataxia Telangiectasia↗

Normal human B cells display ordered light chain gene rearrangements and deletions.

Human kappa-producing B cell lines and leukemias retain their excluded lambda light chain genes in the germ line configuration, whereas transformed lambda-producing B cells uniformly rearrange or delete their kappa genes (12). Whether the unexpected lambda gene recombinations within malignant lambda-producing B cells reflect a normal developmental process or are secondary to transformation and specific chromosomal translocations was uncertain. To resolve this issue, we purified circulating lambda-bearing B cells from a normal individual to 97% purity by using a series of negative selection steps and a final positive selection on a cell sorter. Over 95% of the collective kappa genes in these lambda B cells were no longer in their germ line form, with the majority (60%) deleted and the remainder present but in a rearranged state. The chromosomal loss of the germ line kappa genes included the joining (J kappa) segments as well as the constant (C kappa) region, yet the particular variable (V kappa) gene family studied was spared. In addition, the incidence of kappa gene deletions was higher in long-term than in freshly transformed lambda B cell lines. This implies that the deletion of aberrantly rearranged kappa genes may occur as a second event. Such a mechanism would serve to eliminate aberrant transcripts and light chain fragments that might interfere with the synthesis and assembly of effective immunoglobulin molecules. Thus, despite the nearly equal usage of kappa and lambda light chain genes in man, there appears to be a sequential order to their expression during normal B cell ontogeny in which kappa gene rearrangements precede those of lambda.

B-Lymphocytes↗

B cell, helper T cell, and suppressor T cell abnormalities contribute to disordered immunoglobulin synthesis in patients following bone marrow transplantation.

The pathogenic mechanisms responsible for the hypogammaglobulinemia that occurs in patients who have undergone bone marrow transplantation were studied using peripheral blood lymphocytes in an in vitro immunoglobulin biosynthesis assay. None of the nine marrow recipients between 2 and 15 months after transplantation produced normal amounts of IgG, IgA, or IgM in response to pokeweed mitogen (a T cell-dependent activator). However, three of these same patients responded to Epstein-Barr virus (a helper T cell- independent activator), suggesting that these three possessed responsive B cells. Cocultures of the marrow recipients' lymphocytes with lymphocytes from their respective donors or other normal subjects documented excessive suppressor cell activity in five cases. These suppressor cells frequently had profound activity (greater than 80% suppression of the immunoglobulin synthesis of cocultured normal cells), were predominantly radioresistant, and were T cells in the cases where analyzed. Helper T cell activity for immunoglobulin synthesis was not demonstrable in seven of the nine cases. In addition, four of the patients apparently possessed defective B cells. Although most patients had combined defects of several lymphocyte subpopulations, it appeared that either an isolated helper T cell or isolated B cell deficiency was sufficient to result in altered Ig synthesis. In this regard, two patients had demonstrable helper T cell defects with partially responsive B cells and no excessive suppressor activity. Interestingly, these two patients were experiencing a recurrence of their hypogammaglobulinemia following a period of normalized immunoglobulin levels. Thus, defects within all lymphocytic elements involved in the response and regulation of immunoglobulin synthesis were identified and may contribute to the humoral immunodeficiency which follows marrow transplantation.

Adolescent↗

Characterization of a soluble suppressor of human B cell immunoglobulin biosynthesis produced by a continuous human suppressor T cell line.

A human suppressor T cell maintained in long-term culture with conditioned medium containing interleukin 2 elaborates a suppressor factor(s) that specifically inhibits human polyclonal B cell immunoglobulin biosynthesis. This soluble immune suppressor supernate of immunoglobulin production (CTC-SISS-B) shares a number of features with the previously described suppressive mediator elaborated by concanavalin A-activated human peripheral T cells (SISS-B) including: (a) the inhibition by a noncytotoxic mechanism, (b) the suppression of immunoglobulin biosynthesis either through direct action on the B cell or indirect action via the monocyte, (c) the loss of inhibition in the presence of the monosaccharide L-rhamnose, (d) the elaboration by cells irradiated with 500 ro 2,000 rad, and (e) molecular weights of 60,000--90,000. Furthermore, the suppression by this mediator appears to be specific for B cell immunoglobulin production in that CTC-SISS B has no effect on T cell proliferation to mitogens, antigens, an allogeneic cells or on T cell-mediated cytotoxicity. These data indicate that one possible mechanism of suppressor T cell inhibition of human immunoglobulin production is via the generation of a lectinlike suppressor lymphokine that interacts with defined saccharide determinants on the cell surface of either the B cell or monocyte.

Animals↗

Stimulation of immunoglobulin biosynthesis in human B cells by wheat germ agglutinin. I. Evidence that WGA can produce both a positive and negative signal for activation of human lymphocytes.

Wheat germ agglutinin (WGA), previously regarded strictly as a nonmitogenic or anti-mitogenic lectin, can under appropriate conditions markedly stimulate in vitro synthesis and secretion of immunoglobulin (Ig) by human B lymphocytes. Stimulation of Ig production by WGA is 1) confined to a narrow lectin dose range (2 to 10 micrograms/ml; 2) abrogated by the simple sugar N-acetyl-D-glucosamine but not by a variety of other monosaccharides; 3) effective only after early additions of WGA within the initial 72 hr of 12-day cultures; 4) detected in the presence of B and T cells but not B cells alone; and 5) polyisotypic in nature, as indicated by augmented synthetic rates of Ig in each of 3 major classes (IgG, IgA, and IgM). With few exceptions, WGA produces equivalent or greater rates of Ig production as obtained in cultures activated with pokeweed mitogen (PWM), a well-recognized T-dependent polyclonal activator of human B cells. Furthermore, periperal blood lymphocytes from select individuals that respond weakly to PWM are markedly stimulated with WGA. In contrast to these stimulatory effects of WGA on Ig production by lymphocytes exposed to low lectin concentrations, addition of WGA in amounts greater than 15 micrograms/ml to PWM-stimulated human lymphocyte cultures produces marked suppression of the expected level of Ig synthesis. These data indicate that varying doses of WGA can produce contrasting stimulatory and inhibitory effects on human B cell metabolism.

Acetylglucosamine↗

The Sézary syndrome: a malignant proliferation of helper T cells.

The Sézary syndrome is a frequently lethal disease characterized by circulating malignant cells of thymus-derived (T)-cell origin. The capacity of circulating malignant lymphocytes from patients with this syndrome to synthesize immunoglobulins and to function as helper or suppressor cells regulating immunoglobulin synthesis by bone marrow-derived (B) lymphocytes was determined. Peripheral blood lymphocytes from normal individuals had geometric mean immunoglobulin synthetic rates of 4,910 ng for IgM, 1,270 ng for IgA, and 1,625 ng for IgG per 2 X 10(6) cells in culture with pokeweed mitogen for 7 days. Purified normal B cells had geometric mean synthetic rates of 198 ng for IgM, 145 ng for IgA, and 102 ng for IgG. Leukemic cells from patients with the Sézary syndrome produced essentially no immunoglobulins. Adding normal T cells to normal B cells restored their immunoglobin producing capacity. Leukemic cells from four of five patients tested had a similar capacity to help immunoglobulin synthesis by purified normal B cells. Additionally, Sézary cells from one patient studied induced a nearly 10-fold increase in IgA synthesis by lymphocytes from a child with ataxia telangiectasia and selective IgA deficiency. Furthermore, these Sézary cells induced more than a 500-fold increase in IgG and IgA synthesis by lymphocytes from a child with Nezelof's syndrome. When Sézary cells were added to normal unfractionated lymphocytes, they did not suppress immunoglobulin biosynthesis. In addition, unlike the situation observed when large numbers of normal T cells were added to purified B cells, there was no depression of immunoglobulin synthesis at very high malignant T-cell to B-cell ratios. These data support the view that Sézary T cells do not express suppressor cell activity. The results presented in this paper suggest that neoplastic lymphocytes from the majority of patients with the Sézary syndrome originate from a subset of T cells programmed exclusively for helper-like interactions with B cells in their production of immunoglobulin molecules.

Adult↗

Hycanthone and its congeners as bacterial mutagens.

Hycanthone methanesulfonate (HCT) was shown to induce "forward" and "reverse" mutations in Salmonella typhimurium and Escherichia coli. Mutational effects of HCT on S. tyhhimurium TA1532 were concentration and time dependent. A comparison of mutagenic potency for TA1532 was made between HCT and the frame-shift mutagens quinacrine and ICR-191. An investigation of structure-activity relationships revealed the substituent in the 4-position of ring A to be critical for mutagenicity. Activity was found when this group was a hydroxymethyl (i.e., HCT) or an aldehyde (Win 25,315), but the analogues having a carboxyl group (Win 25,850) or methyl group (lucanthone) in this positionwere inactive. Removal of a single ethyl group from the side chain did not affect mutagenic activity inasmuch as the potency of desethyl HCT (Win 27,262) equaled that of HCT on a molar basis. A marginal activity was found with a sample of HCT sulfoxide (win 27,266), but this sample was found to contain traces of HCT. The HCT analogue with a terminal N-oxide in the side chain (Win 29,329) was inactive at the concentration tested.

Bacteria↗

Physiologic responses of REVC, a continuous rabbit endothelial vascular cell.

Endothelial cells (EC) are fastidious in their growth requirements in vitro and will not survive extensive passages. We have partially characterized a continuous cell line (> 40 passages) established in culture from New Zealand White rabbit vena cava endothelium (REVC). REVC cells resemble typical EC, but remain hardy when grown on uncoated plastic in DMEM/F12 + 10% FBS. REVC cells have typical cobblestone appearance, are contact-inhibited in monolayers and express factor VIII-related antigen. Weibel-Palade bodies were not seen by electron microscopy. REVC cells grown in 2% FBS on plastic demonstrate dose-dependent increases in [3H]thymidine uptake in response to acidic FGF (10-100 ng/ml), basic FGF (3-100 ng/ml), EGF (10-50 ng/ml), and ECGS (10-100 micrograms/ml). Heparin (5-100 micrograms/ml) potentiates proliferation induced by aFGF and lowered the ED50 for aFGF. REVC cells did not show an increased proliferative rate in response to vascular endothelial growth factor. Transforming growth factor beta 1 and beta 2 profoundly inhibited thymidine uptake at doses as low as 100 pg/ml. When grown on a collagen I substratum, REVC cells became larger, more polygonal and assumed a sheet-like appearance upon reaching confluence. REVC cells plated on fibronectin, laminin or poly-L-lysine demonstrated increases in pericellular granularity and pronounced spreading, especially on fibronectin. Phorbol myristate acetate produced profound morphological changes characterized by swirling whorls of bipolar cells surrounding patches of polygonal cells and multilayered overgrowth. When plated on EHS (Engelbreth-Holm-Swarm) tumor extracellular matrix (Matrigel), REVC cells became quiescent and underwent morphological changes reminiscent of differentiation with elongated cytoplasmic extensions. Chromosomal examination of REVC cells revealed a normal diploid karyotype (2n = 44). This continuous cell line is undergoing further characterization and may be quite useful in investigating many aspects of endothelial cell biology in vitro.

Animals↗