bluuebunny/crossref_metadata_2025 huggingface dataset:
Natural killer cells generated from bone marrow culture.
Authors: Koo G C , Peppard J R , Mark W H
Published: December 2022

By using anti-Nk-1 antiserum, we detected a significant proportion of Nk-1+ cells in bone marrow (BM) with low lytic activity that can be slightly enhanced with interferon (IF). These BM Nk-1+ cells also bind to YAC-1 cells. Because Nk-1 antigen has been found to mark NK cells, BM appears to harbor immature precursors to natural killer (NK) cells. We therefore used concanavalin A (Con A)-conditioned medium to culture BM cells to induce differentiation of the putative NK precursors. After 3 to 4 days in culture, cytotoxic activity to YAC, that peaked at 6 to 7 days, was consistently generated, and the activity still could be detected after 10 to 14 days in culture. In contrast, experiments using spleen cultures, performed in a similar manner, showed peak activity after 4 to 5 days and the activity declined thereafter. The cytotoxic activity of cultured BM cells was also higher than that of cultured spleen cells. Cultures of BM cells from old mice have good cytotoxic activity. The cytotoxic cells generated were Nk-1+ and Qa-5+. Furthermore, these culture conditions did not maintain the proliferation of CFU-C cells.
Effect of pregnancy on augmentation of natural killer cell activity by Corynebacterium parvum and Toxoplasma gondii.
Authors: Luft B J , Remington J S
Published: December 2022

Studies were performed to determine the effect of pregnancy on NK cell activity and the augmentation of NK cell activity which normally follows injection of killed C. parvum or live T. gondii. When compared to cells from virgin mice, peritoneal and splenic cells from unstimulated pregnant mice showed no significant difference in NK activity. In contrast, NK activity of peritoneal cells from pregnant mice that received C. parvum or T. gondii was significantly lower than that found in comparably treated virgin mice. This reduced augmentation of NK activity in the peritoneal cells of pregnant mice could not be altered by the removal of plastic-adherent cells or of T cells by treatment with anti-Thy-1.2 antibody and complement. The number of effector-target conjugates was quantitated with a single cell assay, and was found to be comparable between cells from treated pregnant mice and treated virgin controls. However, the magnitude of lysis of target cells by peritoneal and splenic effector cells from pregnant mice previously injected with C. parvum was markedly and significantly reduced when compared to cells from comparably treated virgin mice. Thus, pregnancy is associated with an impaired ability to augment NK activity. This decrease in NK activity was not due to the depletion or dilution of NK cells, but to a functional impairment of the individual NK cells.
Anti-idiotypic antibodies in a patient with monoclonal rheumatoid factor after pneumococcal bacteremia.
Authors: Abe T , Takeuchi T , Kiyotaki M , Koide J , Hosono O , Homma M , Otake T , Kano S
Published: December 2022

A 51-yr-old Japanese female patient with monoclonal IgM gammopathy with rheumatoid factor activity was admitted because of pneumococcal bacteremia. About 2 wk after admission, her rheumatoid factor activity became undetectable by RAHA test and radioimmunoassay, subsequent to the initial marked elevation. The suppressive capacity of the patient's IgG fraction on the rheumatoid activity of her monoclonal IgM on January 11 was determined. The IgG fraction obtained on February 22 blocked the binding of the rheumatoid factor to rabbit IgG. The suppressive activity in the IgG fraction of February 22 was shown to be localized within the F(ab')2 fragment. Furthermore, the specificity of the suppressive serum factor was shown by the inability to block the binding of SRBC coupled with diazotized phosphorylcholine to anti-pneumococcal antibody. Thus, the marked reduction of rheumatoid factor activity was considered to result from anti-idiotypic antibody transiently appearing in her serum after pneumococcal bacteremia.
Interferon induction in mouse spleen cells by mitogenic and nonmitogenic lectins.
Authors: Ito Y , Tsurudome M , Yamada A , Hishiyama M
Published: December 2022

Twenty-two species of lectin were tested for their ability to induce interferon (IFN) in mouse spleen cells. Twenty-two species of lectins representing four groups, based on competition patterns with monosaccharides, were examined for their ability to induce IFN in cultured mouse spleen cells. The lectins, all belonging to the third group (concanavalin A, succinylated concanavalin A, Lens culinaris lectins type A and B, and poke weed mitogen) induced IFN mainly composed of IFN gamma. They were either T cell or T/B cell mitogens. Five nonmitogenic lectins, Lotus tetragonolobus seed lectin, crude and type II lectins of Ulex europeus, Bandeiraea simplicifolia type II and Salanum tuberosame lectins, and wheat germ agglutinin belonging to either the first or the third group, induced IFN beta. The production of IFN during stimulation IFN beta- and IFN gamma-inducing lectins followed different kinetic curves. WGA induced IFN in circulation when injected i.p. in mice, and a peak titer was found 2 hr after inoculation.
Lymphocyte modulation of fibroblast function in vitro: stimulation and inhibition of collagen production by different effector molecules.
Authors: Postlethwaite A E , Smith G N , Mainardi C L , Seyer J M , Kang A H
Published: December 2022

Increased collagen deposition is a common feature of granulomatous and nongranulomatous inflammation associated with certain types of cell-mediated immune reactions in vivo. In the present study, we found that normal human peripheral blood mononuclear leukocytes cultured in vitro and stimulated by antigens or T cell mitogens release a 100 to 170 K m.w., heat-labile, trypsin-sensitive protein that stimulates dermal fibroblasts to produce increased quantities of type I and III collagens. Our data suggest that this collagen production protein is of T lymphocyte origin and that it preferentially stimulates production of collagen. We also observed that human mononuclear leukocytes release a different effector molecule with an m.w. of 55 K that inhibits fibroblast collagen production. Mononuclear leukocytes in culture are capable of releasing both the stimulator and the inhibitor of collagen production. The relative amounts of each of these factors elaborated by mononuclear leukocytes in culture appear to be influenced by several variables, such as cell density, type of stimulant used, and the duration of the culture period. These observations suggest that collagen production by fibroblasts in close proximity to sites in vivo where cell-mediated immune reactions are occurring might be regulated by both of these effector molecules.
Immunoselection of B cell hybridomas with anti-idiotypic antisera to study the role of heavy and light chains for idiotype expression and antibody activity.
Authors: Ju S T , Pincus S H , Kunar J , Dorf M E
Published: December 2022

Conventional reconstitution experiments with heavy (H) and light (L) offins of hybridoma anti-poly-(Glu60Ala30Tyr10) (anti-GAT) antibodies demonstrated that H and L chains are required for efficient expression of anti-GAT activity and the previously defined common CGAT idiotype. On the basis of this observation, we treated a CGAT+ hybridoma cell line (F9.195.6), which was produced by fusion with an MOPC 21 (gamma 1, K) secretor line, with anti-CGAT idiotypic antibodies plus complement to select CGAT-variants. Such treatment greatly enhanced the frequency of isolating hybridoma variants. Molecules secreted from these variants bear anti-GAT mu-chain and MOPC 21 L chain (as judged by serology and Southern blot studies), lack GAT binding activity and CGAT idiotype, and exhibit a "new" private idiotype (E8). Anti-private idiotypic sera were successfully used to select a series of CGAT+, E8- clones that secrete molecules bearing only the appropriate anti-GAT mu- and K chains. From E8- hybridoma supernatants, CGAT- molecules bearing MOPC 21 H chain and anti-GAT L chain could be obtained. The data indicate that immunoselection of hybridoma clones with anti-idiotypic antibodies is a convenient means of preparing reconstituted antibody molecules. Furthermore, the data demonstrate that CGAT idiotype determinants are expressed on antibody molecules composed of appropriate H and L chains.
Analysis of structural properties and cellular distribution of avian Ia antigen by using monoclonal antibody to monomorphic determinants.
Authors: Ewert D L , Munchus M S , Chen C L , Cooper M D
Published: December 2022

In this report, we describe the analysis of Ia-like antigens in the chicken by using a monoclonal antibody (CIa-1) reactive with monomorphic determinants of the Ia-like (B-L) antigens. This antibody reacts with determinants on B cells in all avian species tested, but does not detect antigens on lymphocytes of representative mammals, reptiles, and amphibians. In addition to B cells, this antibody defines a subpopulation of the monocyte-macrophage series and reacts with mitogen-activated T cells. Immunochemical analysis indicates that the CIa-1 reactive antigen is a 65,000-dalton glycoprotein consisting of an alpha-chain of 32,000 daltons noncovalently bound to a beta-chain of 27,000 daltons. Under nonreducing conditions, the beta-chain migrates with slightly faster mobility. Two-dimensional gel analysis indicates that the beta-chain is the more heterogeneous of the two chains. Thus, the antigen detected by CIa-1 antibody is similar in cell distribution and structure to the murine Ia antigens and human DR antigens. During in ovo development, Ia+Ig- cells were not found in the yolk sac but were detected in the spleen, mesonephros, and bursa of 9-day embryos. Two populations of Ia+Ig- cells were identified in the bursa: 40 to 60% of the bursacytes, mostly larger cells, exhibited brighter immunofluorescence reactivity than the smaller bursacytes.
Functional angiotensin II receptors on macrophages from isolated liver granulomas of murine Schistosoma mansoni.
Authors: Weinstock J V , Kassab J T
Published: December 2022

Isolated liver granulomas from mice infected with Schistosoma mansoni contain components of the renin-angiotensin system. Angiotensin II is a major biologically active component of this system. It was therefore determined whether inflammatory cells within the granuloma possessed receptors for this hormone. Specific binding of angiotensin II to isolated granuloma macrophages was demonstrated by both fluorescence and radioligand assays. The binding of 125I-angiotensin II was saturable, dependent on radioligand concentration, and reversible. Scatchard analysis of binding data suggested a Kd of 0.25 nM with 526 binding sites per cell. The natural analogs of angiotensin II, angiotensin I and III, only weakly competed for angiotensin II binding sites. Exposure of macrophages to appropriate binding concentrations of angiotensin II resulted in a rapid dose-dependent increase in intracellular cAMP. It is therefore concluded that granuloma macrophages possess functional receptors for angiotensin II.
Cell surface antigen phenotypes of MCF-induced thymic lymphomas in AKR mice.
Authors: Yetter R A , Morse H C
Published: December 2022

The hypothesis that the surface antigen phenotypes of MCF-MuLV-induced thymic lymphomas in AKR mice are predictable and characteristic of the inducing virus has been tested. Thymic lymphomas induced by two different MCF-MuLV were assayed by flow microfluorometry for their expression of the surface antigens XenCSA, Thy-1.1, Ly-2, Ly-1, 2C2, H-2K, and Ia. In all cases there was an increase in XenCSA levels. The lymphomas could be divided into three categories on the basis of qualitative difference in Ly-2 expression: Ly-2+ tumors, Ly-2- tumors, and tumors with both Ly-2+ and Ly-2- populations. One lymphoma expressed 2C2, an antigen not normally found on thymocytes. Quantitative differences in expression could be found for all antigens. This variation in surface antigen phenotype was independent of the cloned virus MCF used to induce the lymphoma.
Suppression of Con A mitogen-induced proliferation of normal spleen cells by macrophages from chickens with hereditary muscular dystrophy.
Authors: Kline K , Sanders B G
Published: December 2022

Spleen cells from chickens with hereditary muscular dystrophy (MD) give low blastogenic responses to the T cell mitogen concanavalin A (Con A) while exhibiting normal mitogen stimulated blastogenic responses to the T cell mitogen phytohemagglutinin (PHA). The addition of MD spleen cells to normal spleen cells caused a marked suppression of the Con A response of the normal cells while not affecting the PHA response of the normal cells. The suppressive activity by the MD spleen cells requires viable cells and is contact mediated. The suppressive activity is attributed to the presence in MD spleens of a population of suppressor cells with characteristics typical of macrophages. The suppressor cell activity was not removable by complement-mediated lysis using anti-T or anti-B sera, but it was reversible by treatment with carrageenan or carbonyl iron magnet, by passage through a Sephadex G-10 column, and by adherence to plastic petri dishes or glass beads. MD spleen cells depleted of the suppressor cell population remained unable to respond to Con A.
Immunomodulatory effects of corticosteroids on natural killer and antibody-dependent cellular cytotoxic activities of human lymphocytes.
Authors: Nair M P , Schwartz S A
Published: December 2022

The in vitro effect of prednisolone (PRD) on NK and ADCC activities of human lymphocytes was investigated. PRD at concentrations ranging from 7.5 X 10(-3) to 1 X 10(-5) M significantly inhibited NK activity, while concentrations of 7.5 X 10(-3) to 1 X 10(-4) M inhibited ADCC activities of PBL when added directly to the mixture of effector and target cells. Lymphocytes pre-cultured for 24 hr with PRD at concentrations ranging from 1 X 10(-4) M to 1 X 10(-6) M showed significant suppression of their NK activity. Inhibition was proportional to the concentration of the drug, and was observed at as early as 1 hr of incubation at various effector to target cell ratios with several targets. PRD also inhibited NK and ADCC activities of purified T cells, non-T cells, and NK-enriched effector cells. In target-binding assays, PRD decreased the target-binding capacity of effector lymphocytes in a dose-dependent manner. PRD-induced inhibition could be reversed by incubating lymphocytes for 1 hr with interferon or IL 2. Pretreatment of targets with PRD for 4 hr did not affect cytotoxic activity. Inhibition of cytotoxicity was not due to direct toxicity to effector cells because lymphocytes treated with PRD showed normal spontaneous 51Cr release, and their viability after 24 hr of pre-culture with PRD was comparable to that of untreated control cells. These results demonstrate that PRD has significant immunomodulatory effects on human NK and ADCC activities that may be of clinical relevance.
Beta-endorphin and met-enkephalin stimulate human peripheral blood mononuclear cell chemotaxis.
Authors: van Epps D E , Saland L
Published: December 2022

The neuropeptides beta-endorphin and met-enkephalin are potent analgesics and have a broad spectrum of biologic activities including the recently described alterations of lymphocyte proliferation and antibody production. The current study demonstrates that beta-endorphin and met-enkephalin stimulate human mononuclear cell chemotaxis, as measured by the in vitro leading front assay for migration. The response to both beta-endorphin and met-enkephalin was bimodal, with peak activities occurring at 10(-12) M and 10(-8) M. The distance migrated in response to optimal concentrations of beta-endorphin or met-enkephalin was approximately 80% of that obtained with 10(-8) M formyl-methionyl-leucyl-phenylalanine (f-MLP) and was blocked by prior incubation with 10(-8) M naloxone. Removal of glass adherent cells resulted in a loss of the response to beta-endorphin. Quantitation of the number of cells responding to beta-endorphin showed that only about 50% as many cells responded to beta-endorphin as compared with f-MLP. Human neutrophils showed some migration in response to beta-endorphin and met-enkephalin, although the average optimal migration was less than 30% of that observed with 10(-8) M f-MLP. Studies of the in vivo infusion of beta-endorphin into the cerebral ventricle of the rat resulted in the immigration of macrophage-like cells and are consistent with the in vitro evidence for a chemotactic effect of beta-endorphin.
Inhibition of T suppressor cell expression by histamine type 2 (H2) receptor antagonists.
Authors: Griswold D E , Alessi S , Badger A M , Poste G , Hanna N
Published: December 2022

The effect of histamine type 2 (H2) receptor antagonists, cimetidine and ranitidine, on the induction and expression of hapten-specific suppressor T cells was studied. The activity of DNBSO3 -induced suppressor cells was evaluated after adoptive transfer to naive syngeneic recipients. Treatment with cimetidine or ranitidine markedly inhibited suppressor T cell activity in a dose-related manner and enhanced the contact sensitivity response to DNFB. Both H2 antagonists were effective in inhibiting the expression and, to a lesser extent, the induction of suppressor T cells. In contrast, norburimamide , a non-H2 antagonist structurally related to cimetidine, was inactive. The relevance of these findings to the clinical observation of cimetidine-induced reversal of acquired tolerance to dinitrochlorobenzene in anergic patients is discussed.
Effects of deoxycoformycin in mice. I. Suppression and enhancement of in vivo antibody responses to thymus-dependent and -independent antigens.
Authors: Ratech H , Bell M K , Hirschhorn R , Thorbecke G J
Published: December 2022

The effect of 2'-deoxycoformycin (DCF) on the PFC responses of AKR mice to SE, TNP-Ficoll, and TNP-B. abortus was examined. Subcutaneous injection of DCF 4 days before antigen caused suppression of all three responses by 70 to 78%. In contrast, injection of DCF 1 day after antigen caused enhancement of both the anti-SE and the anti-TNP-Ficoll responses. Although a single high dose of cortisone acetate injected 4 days before antigen caused a similar suppression, the effect of DCF was not mediated via a steroid release, inasmuch as DCF also suppressed the immune response in adrenalectomized mice. The response of BALB/c mice to TNP-Ficoll was also inhibited by DCF pretreatment and enhanced by injection of DCF after antigen. In contrast, in athymic mice DCF caused suppression of the anti-TNP-Ficoll PFC response, whether injected before or after antigen. These results are interpreted as suggesting that DCF causes suppression primarily via an effect on B cells. The enhancement seen in normal but not in athymic mice may possibly be ascribed to an effect on suppressor T cells. Apparently the enhancement of both TD and TI responses caused by DCF injected 1 day after antigen in normal mice is the net result of these two opposing effects. The results imply that helper T cells are resistant to DCF.
Effects of deoxycoformycin in mice. II. Differences between the drug sensitivities and purine metabolizing enzymes of transplantable lymphomas of varying immunologic phenotypes.
Authors: Ratech H , Kim J , Asofsky R , Thorbecke G J , Hirschhorn R
Published: December 2022

Transplantable BALB/c and AKR lymphomas of different cell surface immunologic phenotypes have distinctive patterns of response to the ADA inhibitor DCF in vivo and in vitro. BAL 9, a lymphoma of the Lyt-1+,2+ T cell phenotype, was the most sensitive to DCF in vivo, and its DNA synthesis was inhibited more than 95% when cultured in the presence of dAr and DCF in vitro. This was correlated with a 10-fold increase in dATP content. The ADA and AMPDA activities were both high. Two lymphomas of the Lyt-1-,2+ T cell phenotype, BAL 5 and AKTB - lt , as well as two B cell phenotype lymphomas, A20 .3 and AKTB -lb, were all moderately inhibited in their in vivo growth if enough DCF was administered. However, their DNA synthesis in vitro was only inhibited 8 to 24% by dAr and DCF, there was only a twofold increase in the accumulation of dATP, and ADA and AMPDA activities were both low in the two BALB/c lymphomas tested. BAL 13, the only lymphoma of the Lyt-1+,2- phenotype examined, was completely resistant to DCF in vivo and in vitro. When cultured in the presence of dAr and DCF there was a transient increase in dATP content, followed by an abrupt decline. AMPDA activity was five to seven times greater than in the other lymphomas tested. ADA activity was moderate. The activities of 5' nucleotidase and of adenosine kinase were low and approximately equal in all the BALB/c lymphomas. These results suggest that the response to DCF by lymphomas of various immunologic phenotypes can be correlated with their nucleoside metabolism. The sensitivity of BAL 9 and the resistance of BAL 13 to DCF are correlated with their tendency to accumulate dATP and with their AMPDA and ADA activity ratios. The moderate sensitivity to DCF in vivo of the other T and B cell lymphomas, however, could not be clearly explained by any of the in vitro parameters thus far investigated, and this suggests that mechanisms inhibiting lymphoma proliferation other than dATP accumulation may be operating.
Characteristics of amplifier T cells involved in the antibody response to the capsular polysaccharide of type III Streptococcus pneumoniae.
Authors: Taylor C E , Stashak P W , Chiang J , Leiserson W M , Caldes G , Prescott B , Baker P J
Published: December 2022

Amplifier T cell activity can be transferred by spleen cells harvested 72 hr after priming with type III pneumococcal polysaccharide (SSS-III) and can be abolished by treating the transferred cells with monoclonal anti-Lyt-1, or anti-Thy-1 antibodies in the presence of complement; thus, amplifier cells represent a distinct subpopulation of T cells. Amplifier T cells were found to be sensitive to irradiation but not to treatment with cyclophosphamide. When amplifier cells were transferred to athymic nude (nu/nu) mice, the enhancement obtained was much greater than that produced in thymus-bearing (nu/+) mice; this is presumably due to the lack of suppressor T cell activity in nu/nu mice that enables amplifier T cell activity to be expressed more fully. Amplifier T cells also were found to be present in peripheral blood; these amplifier T cells were Lyt-2- in phenotype. Although the induction and activation of amplifier T cells appear to be antigen-specific, the product made by amplifier T cells may not be antigen specific in its mode of action. Because amplifier T cells can be induced and activated by exposure to immune B cells, specificity is presumably due in whole or in part to the ability of amplifier T cells to recognize the idiotypic determinants of B cell-associated antibody specific for SSS-III.
Stage-specific and common antigens of Brugia malayi identified with monoclonal antibodies.
Authors: Canlas M M , Piessens W F
Published: December 2022

To identify parasite antigens that trigger protective, pathogenic, and allergic immune responses during filarial infections, we generated a series of monoclonal antibodies to infective larvae, adult worms, and microfilariae of Brugia malayi, a human pathogen. Quantitative and qualitative analysis of the reaction patterns of these monoclonal antibodies indicates the existence of stage-specific antigens of B. malayi, as well as of antigens shared by different stages of this parasite and by other related and unrelated helminths. These antibodies should provide invaluable tools for the analysis of host-parasite interactions in filariasis at the molecular level.
Large granular lymphocytes provide an accessory function in the in vitro development of influenza A virus-specific cytotoxic T cells.
Authors: Burlington D B , Djeu J Y , Wells M A , Kiley S C , Quinnan G V
Published: December 2022

We report that large granular lymphocytes (LGL) have an accessory function in the development of cytotoxic T cells (Tc) through the production of soluble factor(s). LGL and T cells were separated on Percoll gradients and the ability of the separated and of the recombined LGL and T cells to generate influenza A virus-specific Tc activity was measured. When stimulated by virus-infected, irradiated, adherent cells, neither LGL nor T cells cultured separately produced Tc activity. When they were co-cultured, however, even if separated by a 0.22-micron pore size membrane, Tc responses were readily generated from the small T cell precursors and natural killer activity was maintained in the LGL. Thus, LGL were required as accessory cells for Tc responses to occur and the effect was mediated by a soluble factor(s). alpha-Interferon (IFN) was produced in cultures containing LGL and/or stimulating adherent cells, whereas gamma-IFN was only produced in cultures containing both LGL and T cells. Therefore, neither alpha- nor gamma-IFN appeared to be the LGL produced soluble factor that mediated the accessory effect of LGL on Tc responses.
Use of JH4 joining segment gene by an anti-arsonate antibody that bears the major A-strain cross-reactive idiotype but displays diminished antigen binding.
Authors: Slaughter C A , Jeske D J , Kuziel W A , Milner E C , Capra J D
Published: December 2022

One of the antibody families utilized by the A/J mouse in its response to p-azophenylarsonate (Ars) is characterized by the expression of the major anti-arsonate cross-reactive idiotype (CRI) of the A strain. This family has been termed the Ars-A family. A hybridoma antibody (HP 101F11 ) obtained after immunization of an A/J mouse with Ars was identified initially as displaying the CRI, but was subsequently found to bind antigen at a level much lower than most members of the Ars-A family. The results of binding studies suggested that HP 101F11 possesses reduced avidity for antigen. When isolated light and heavy chains were allowed to recombine with the heavy and light chains of a strongly antigen-binding, strongly CRI-positive antibody of the Ars-A family (HP 93G7 ), the low level of antigen binding by HP 101F11 was found to be due to a structurally variant heavy chain. Whereas antibodies of the Ars-A family with normal avidity for antigen had been shown to use the JH2 joining segment gene, amino acid sequence analysis of HP 101F11 revealed that this antibody has a JH segment with a sequence identical to that encoded by a portion of a different JH gene, JH4 . The implication that 101F11 uses the JH4 gene instead of JH2 was supported by the observation that the productively rearranged gene is associated with an Eco R1 restriction fragment 0.95 Kb smaller than the corresponding fragments of Ars-A hybridomas with normal avidity for antigen. The size difference of 0.95 Kb corresponds exactly to the known distance between the JH2 and JH4 genes in BALB/c germline DNA. In addition to the structural differences immediately attributable to the use of JH4 , HP 101F11 has shown an amino acid interchange in the DH segment, and a single amino acid deletion at the DH-JH boundary. These results show that variation among members of the Ars-A family in the DH and/or JH segments provides alternative structural forms of Ars-A antibodies upon which selective processes can operate during the course of an immune response.
Compared mechanisms of tumor cytolysis by human natural killer cells and activated polymorphonuclear leukocytes.
Authors: Abrams S I , Brahmi Z
Published: December 2022

The mechanism(s) of natural killer (NK) cell-mediated cytotoxicity (CMC) remains largely unknown. In this study, we investigated the possibility of human NK cells to exhibit an oxidative burst (OB) after stimulation by K562, an NK-sensitive target cell (TC). The addition of catalase (CAT) or superoxide dismutase (SOD) to the NK-mediated cytotoxic assay had no effect on NK-CMC. In contrast, CAT and SOD effectively modulated the cytotoxicity mediated by phorbol-12-myristate-13-acetate (PMA)-activated polymorphonuclear leukocytes (PMNL) against three different tumor TC, including K562. CAT abrogated, while SOD enhanced PMA-activated PMNL-mediated cytotoxicity. The synergistic effect of SOD and PMA was suppressed in a dose-dependent fashion by CAT. Furthermore, by chemiluminescence (CL) and SOD-inhibitable reduction of cytochrome c, we failed to detect an OB associated with K562-stimulated NK cells. PMNL, however, rapidly responded to PMA (10 ng/ml), generating almost 10(6) cpm within 20 min and 26.7 nM O-2/10(6) cells/30 min, as detected by CL and reduction of cytochrome c, respectively. Finally, K562 alone, at cell concentrations corresponding to effector cell:target cell (EC:TC) ratios of 1:1 and 1:10, reduced cytochrome c, but this reduction was not inhibited by SOD, thus suggesting a diaphorase activity. Overall, we show that: a) tumor cell destruction by human NK cells and by PMA-activated PMNL is mediated by different mechanisms; and b) NK-CMC against a sensitive TC does not involve an OB.
Inhibition of T cell responses to alloantigens and polyclonal mitogens by Ly-5 antisera.
Authors: Harp J A , Davis B S , Ewald S J
Published: December 2022

The effects of Ly-5 alloantisera on the generation of cytotoxic T cells (CTL), on the effector phase of CTL killing, and on polyclonal mitogenesis were studied. Ly-5 antisera added at the beginning of mixed lymphocyte culture (MLC) suppressed the production of CTL in an allele-specific manner. Neither Ly-5.1 nor Ly-5.2 antisera inhibited the generation of cytotoxic effectors by Ly-5.1/Ly-5.2 heterozygous spleen cells; however, a combination of Ly-5.1 and Ly-5.2 antisera markedly suppressed the appearance of Ly-5 heterozygous CTL. Similarly, Ly-5 antisera inhibited the effector phase of CTL killing in an allele-specific manner. In addition, Ly-5 alloantisera specifically blocked concanavalin A and oxidative mitogenesis of splenocytes carrying the appropriate Ly-5 alloantigen. The results are discussed in light of a possible functional role of Ly-5 molecules in immune processes.
A human alloreactive inducer T cell clone that selectively activates antigen-specific suppressor T cells.
Authors: Mohagheghpour N , Damle N K , Moonka D K , Terrell C P , Engleman E G
Published: December 2022

We showed previously that T cells with the phenotype Leu-3+,8+ are required for the induction of antigen-specific Leu-2+ suppressor cells. Furthermore, when mixed lymphocyte reactions are carried out in the presence of 1 microgram/ml cyclosporin A (CsA), such cultures lead preferentially to the activation of alloantigen-specific suppressor-inducer Leu-3+,8+ cells. In an attempt to generate a clone of T cells with such specific suppressor-inducer properties, we activated Leu-3+,8+ T cells with allogeneic (HLA-DR4+) lymphocytes in the presence of CsA. Clone SP-21, derived by propagating such activated T cells with conditioned medium containing IL 2, is a noncytotoxic, nonsuppressor clone that specifically proliferates to allogeneic cells bearing HLA-DR4 antigen. When cultured with fresh autologous Leu-2+ cells in the absence of HLA-DR4+ cells, clone SP-21 selectively activates Leu-2+ suppressor cells, which inhibit the response of fresh Leu-3+ cells to DR4+ stimulator cells. On the other hand, clone SP-21 fails to induce cytolytic T cells or to help B cell differentiation. These results demonstrate that a T cell clone with a remarkably narrow functional repertoire nonetheless contains and transmits all of the signals necessary for the activation of antigen-specific suppressor cells.
Suppressor T cell recognition of major and minor histocompatibility alloantigens: selected suppression of MHC-directed responses by minor alloantigen Ts.
Authors: Perry L L , Williams I F , Dirusso S
Published: December 2022

The induction of suppression by i.v. administered alloantigens in the murine host was analyzed as a model of the possible effects of blood transfusion on transplant survival. The results indicated that suppressor T cells (Ts) specific for minor histocompatibility alloantigens could be readily induced by the i.v. presentation of minor alloantigen-disparate spleen cells. In contrast, similar priming with cells differing solely at the H-2 major histocompatibility complex stimulated only positive T cell immunity, with no evidence of suppression. The induction of H-2 directed Ts activity could be accomplished only by i.v. priming with major plus minor incompatible donor cells, suggesting that suppressor cell recognition of minor alloantigens may have facilitated the generation of Ts against H-2-encoded major transplantation antigens. A role for minor histocompatibility antigens in the regulation of H-2-specific immunity at the effector level was also indicated. Ts induced by i.v. pretreatment with minor antigen-disparate donor cells not only suppressed the delayed-type hypersensitivity (DTH) response to the relevant minor alloantigens, but also inhibited DTH against unrelated H-2 alloantigens introduced during subsequent intradermal immunization. Suppression of H-2-directed T cell reactivity was specific in that the presence of the Ts-inducing minor alloantigens was also required and occurred only when the minor and unrelated major alloantigens were presented within the same inoculum, if not on the same cell surface. The capacity of Lyt-2+Ts or Ts-derived suppressive factors specific for one set of cell surface molecules to modulate responses to an unrelated group of surface antigens does not appear to represent a general phenomenon, because similar suppression of immunity to unrelated tumor-specific transplantation antigens by minor-specific Ts was not observed. These results are discussed with respect to the possible mechanism of H-2-directed suppression and the role of the I region in Ts recognition of antigen.
Characterization of monoclonal B cell growth factor (BCGF) produced by a human T-T hybridoma.
Authors: Butler J L , Ambrus J L , Fauci A S
Published: December 2022

We previously demonstrated the development of a cloned human T cell hybridoma that secretes B cell growth factor (BCGF) in the absence of demonstrable interleukin 2 or B cell differentiation factor. Sephadex gel filtration chromatography demonstrated the m.w. of this factor to be 18 to 20K. The present studies were performed to further characterize the biochemical properties of the molecule and to determine its target cell specificity. Temperature stability studies showed the monoclonal BCGF to be stable at 37 degrees C for 12 hr and at 70 degrees C for 15 min; however, most (93%) of the activity was lost after incubation at 70 degrees C for 30 min. Aliquots of hybridoma supernatant were exposed to buffer solutions with variable pH with no diminution in activity over a pH range of 4.0 to 10.0 BCGF activity was not affected by 2-mercaptoethanol, neuraminidase, or nucleic acid denaturing enzymes. In contrast, all activity was destroyed by 10 M urea, trypsin, and chymotrypsin. Chromatofocusing demonstrated the isoelectric point of BCGF to be 6.3 to 6.6. Finally, absorption experiments demonstrated that BCGF activity was absorbed by large, activated B cells. Mitogen-stimulated T cell blasts, small resting B cells, and CESS cells failed to absorb BCGF activity from the hybridoma supernatant. These and future studies with purified monoclonal human BCGF should enhance our understanding of its immunochemical properties and of its role in the immunoregulation of human B cell responses.
HLA-DR antigens of autologous melanoma and B lymphoblastoid cell lines: differences in glycosylation but not protein structure.
Authors: Alexander S , Hubbard S C , Strominger J L
Published: December 2022

The HLA-DR antigen expressed on the surface of the human melanoma cell line SK-MEL-37 was characterized and compared with the HLA-DR antigen from the MU B lymphoblastoid cell line originating from the same individual. The HLA-DR heavy chain from SK-MEL-37 cells had an apparent mobility on SDS-PAGE slightly slower than that isolated from MU cells. In contrast, the HLA-DR light chains and the HLA-A,-B heavy chains from the two cell lines had identical mobilities. Double-labeled tryptic peptide mapping and limited N-terminal sequencing showed that the SK-MEL-37 HLA-DR antigen, like all previously examined B lymphoblastoid cell HLA-DR antigens, was homologous to the murine I-E/C subregion antigens and that the mobility difference of the SK-MEL-37 HLA-DR heavy chain was not attributable to differences in the primary structure of the polypeptide. Treatment of the cells with tunicamycin abolished the m.w. difference, suggesting that it was due to a change in glycosylation in SK-MEL-37. This was confirmed by analysis of the glycopeptides from pronase-digested HLA-DR light and heavy chains and HLA-A,B heavy chains purified from the two cell types. The results suggest 1) there is a difference in asparagine-linked oligosaccharide processing in the two cell types, with more of the larger complex glycans synthesized in the melanoma cells than in the B lymphoblastoid cells, 2) the effect is more pronounced with HLA-DR heavy chains than with HLA-DR light chains or HLA-A,B heavy chains, and 3) the oligosaccharide size difference is not solely due to sialic acid content.
Preparation and characterization of monoclonal antibodies reactive with porcine PBL.
Authors: Pescovitz M D , Lunney J K , Sachs D H
Published: December 2022

Partially inbred miniature swine have been developed in this laboratory as a large animal model for immunologic studies. For many of these studies, a source of large quantities of well standardized antibodies to lymphocyte cell surface markers would be extremely helpful. Screening of a large panel of murine anti-human monoclonal antibodies (MAb) for anti-pig cross-reactions was nonproductive. We have therefore prepared a panel of MAb from mice immunized with pig thymocytes. Twenty-six stable MAb were produced that reacted with Ficoll/Hypaque-purified porcine lymphocytes. Reactivity was detected by complement-mediated cytotoxicity and/or cell surface binding ELISA. FMF analysis was performed on unseparated, glass-adherent, nylon wool-adherent, or nylon wool-nonadherent PBL and on cell preparations from lymphoid organs. In addition, the m.w. of the antigens detected by certain of these MAb were determined by immunoprecipitation of extracts of 125I surface-labeled cells. The majority of the MAb were not subpopulation specific. Included in these were 74-11-10 (IgG2b), which was specific for a polymorphic class I MHC determinant, and 76-3-2 (IgG1), which reacted with either a monomorphic class I MHC determinant or beta 2-microglobulin. Another MAb, 74-9-3 (IgM), precipitated a high m.w. complex of three polypeptide chains that appeared similar to that of the common leukocyte antigen. Of special interest were six MAb that were specific for various subpopulations of PBL: 76-7-4 (IgG2a) reacts with peripheral B cells, and 60% of thymocytes but not peripheral T cells, a pattern consistent with the murine ThB antigen; 74-22-15 (IgG1) and 76-5-28 (IgM) react with macrophages and granulocytes; 76-6-7 (IgM) reacts with T cells, macrophages, and granulocytes but not B cells, a combination of reactivities not previously reported in other species; 74-12-4 (IgG2b) and 76-2-11 (IgG2a) react specifically with T cells. 74-12-4 precipitated an antigen of 55,000 m.w., and 76-2-11 precipitated an antigen of 35,000 m.w. The m.w. and tissue distributions suggest that 74-12-4 recognizes porcine T helper cells, whereas 76-2-11 recognizes cytotoxic and/or suppressor T cells.
Organelle-depleted human neutrophil cytoplasts used to study fmet-leu-phe receptor modulation and cell function.
Authors: Gallin J I , Metcalf J A , Roos D , Seligmann B , Friedman M M
Published: December 2022

Organelle-depleted human neutrophil cytoplasts were used to study N-formylmethionylleucylphenylalanine (fmet-leu-phe) receptor regulation and adaptation, aggregation, chemotaxis, and chemoattractant-elicited changes in shape, volume, and surface charge. Cytoplasts aggregated in response to the chemoattractant fmet-leu-phe, but the magnitude of the response was less than that in neutrophils. Unlike neutrophils, cytoplasts did not exhibit a second wave of aggregation with the addition of cytochalasin B and also failed to disaggregate. In chemotactic assays, cytoplasts migrated poorly into cellulose nitrate filters, and compared with intact neutrophils required a 100-fold greater concentration of fmet-leu-phe to elicit shape change. In contrast to neutrophils, cytoplasts did not decrease their surface charge in response to fmet-leu-phe and did not exhibit an increase in the binding of fmet-leu-[3H]phe after stimulation with phorbol myristate acetate. However, receptor adaptation and induced changes in membrane potential, as measured by using the membrane probe di-O-C5(3), were similar in cytoplasts and in neutrophils. The data suggest that the presence of functional intracellular organelles is required for normal aggregation and disaggregation, chemotaxis, and shape change induced by fmet-leu-phe, and also peptide receptor upregulation in response to secretagogues. The data show that peptide receptor adaptation occurs in the absence of secretory granules and is independent of receptor upregulation .
Control of mouse hepatitis virus replication in macrophages by a recessive gene on chromosome 7.
Authors: Smith M S , Click R E , Plagemann P G
Published: December 2022

We have identified and mapped a new locus that imparts resistance to productive infection of mouse hepatitis virus MHV(A59) in cultured macrophages. This locus maps 41.5 centimorgans from the albino locus on chromosome 7.
Monoclonal antibodies to DNA and RNA from NZB/NZW F1 mice: antigenic specificities and NH2 terminal amino acid sequences.
Authors: Eilat D , Hochberg M , Pumphrey J , Rudikoff S
Published: December 2022

Two anti-DNA hybridoma autoantibodies ( A52 , D42 ) were prepared by fusing spleen cells from unimmunized NZB/NZW F1 female mice with BALB/c myeloma cells. The monoclonal antibodies were purified to homogeneity and were analyzed for their antigen-binding specificities. The two anti-DNA antibodies bound single-stranded, double-stranded, and supercoiled DNA, with a marked preference for the single-stranded conformation. Competition experiments performed with synthetic polynucleotides, as well as chain reconstitution experiments, indicated that both the sugar-phosphate backbone and the heterocyclic bases of the nucleic acid are essential for antibody recognition. Amino terminal sequence analysis of A52 and two RNA-binding hybridoma proteins revealed that the heavy chains from all three were members of the VHII subgroup and that the A52 light chain was homologous to the VK8 subgroup. The D42 heavy chain was found to be similar to a phosphocholine-binding hybridoma of the VHIII subgroup.
Lack of adenosine deaminase activity in cultured murine cytotoxic T lymphocytes.
Authors: Minkowski M D , Castellazzi M , Buttin G
Published: December 2022

The level of adenosine deaminase (ADA) activity was investigated in various populations of IL 2-dependent, cultured cytotoxic T lymphocytes (CTL), from bulk cultures as well as from CTL lines (CTL-A and CTL-B types). The study of C57BL/6 derived, cytotoxic bulk cultures yielded the following mean values of ADA activity: 12,500 U/mg in the cortical, immature region of the thymus, 1500 U/mg in the immunocompetent, cortisone-resistant medullary thymocytes, and 2000 U/mg in the T cell population from the spleen. These results are in agreement with previous studies on separated T lymphocyte populations of known origin and further indicate that a fall in ADA activity accompanies T cell maturation. ADA activity was measured in C57BL/6-derived CTL-A lines obtained from the thymic and splenic bulk cultures. All lines were characterized by a very low level of ADA activity, compared with the T cell bulk cultures freshly initiated from the thymic medulla or from the spleen, and to a variety of T tumor lines established in long term culture. Some showed undetectable ADA activity (less than or equal to 20 units/mg), whereas others maintained significant activity (50 to 500 U/mg). No correlation was found between the residual ADA activity level and the killing activity, at the time of the enzyme assay. Identical properties were observed for CTL-B cloned lines of various genetic backgrounds. These results suggest that the level of ADA activity of the CTL in the mouse is lower than the average value of mature T cells of the thymic medulla, and might constitute a differentiation marker specific to the CTL population. A possibility remains that low ADA activity levels in these CTL lines may be the consequence of an extinction of the ADA gene during in vitro growth, as it is observed for the cytotoxic activity itself. In either case, a low ADA activity level is a remarkable property of IL 2-dependent CTL clones, when compared to various established T tumor lines, which exhibit high and stable ADA levels during long term in vitro growth (5000 to 15,000 U/mg).
Pre-B cells in mouse bone marrow: in vitro maturation of peanut agglutinin binding B lymphocyte precursors separated from bone marrow by fluorescence-activated cell sorting.
Authors: Osmond D G , Melchers F , Paige C J
Published: December 2022

Peanut agglutinin (PNA) binding by mouse bone marrow cells and fractionation by the fluorescence-activated cell sorter have previously been shown to separate high concentrations of pre-B cells, as identified by cytoplasmic mu-chains (c mu). PNA+ and PNA- marrow cell fractions have now been assayed for the presence of functional pre-B cells able to generate mature B cells in culture, as defined by three criteria, the appearance of cell surface mu-chains (s mu), immunoglobulin secretion in response to bacterial lipopolysaccharides, and B cell colony formation. Small PNA+ cell fractions contained pre-B cells that developed into mature B lymphocytes in 1/2 to 1 day but did not sustain B cell production. Large PNA+ cells included pre-B cells that gave rise to mature B lymphocytes after an interval of 1 1/2 to 3 days and were able to sustain B cell genesis in vitro for at least 3 to 5 days thereafter. PNA- cell fractions contained mature B cells but lacked pre-B cell activity. The results demonstrate that PNA binding allows the separation of functional subsets of pre-B cells from bone marrow and that the three in vitro assays used in this study are closely comparable with one another as functional pre-B cell criteria. The findings suggest correlations between functional assays, c mu expression, PNA receptors, and cell size in characterizing stages of pre-B cell development.
Molecular genetic analysis of genes encoding the heavy chains of rabbit IgG.
Authors: Martens C L , Currier S J , Knight K L
Published: December 2022

We analyzed the genes which encode the heavy chain constant region of rabbit IgG molecules. Five DNA clones derived from the chromosomal region which spans the C gamma coding sequences were isolated from a recombinant phage library of rabbit liver DNA. Four of these clones can be grouped together by overlaps; together they represent 37 kb of genomic DNA, and contain one C gamma gene and one tentatively identified C epsilon gene. A second C gamma gene was identified which did not overlap with the group of four clones because of restriction site differences found in the flanking regions 5' to the C gamma genes. Nucleotide sequences of the two C gamma genes were identical. Comparisons of the restriction maps of the two cloned C gamma genomic regions suggest that they may represent allelic regions of chromosomes of two different heavy chain haplotypes with polymorphisms in the regions flanking the C gamma genes.