bluuebunny/crossref_metadata_2025_split huggingface dataset:
Activated macrophages secrete a soluble factor that inhibits mitochondrial respiration of tumor cells.
Authors: Kilbourn R G , Klostergaard J , Lopez-Berestein G 
Published: December 2022

Abstract
Conditioned supernatants (CS) obtained from activated murine peritoneal macrophages inhibit tumor cell mitochondrial respiration. EMT-6 cells exposed to CS were markedly inhibited in their ability to oxidize succinate (11.8 ng-atoms 02/min/10(6) cells base line; 3.2 CS treated), malate (15.4 base line, 3.6 CS treated), and tetramethylphenylenediamine (27.6 base line, 10.6 CS treated). The CS was also found to inhibit DNA synthesis in EMT-6 cells (98.9% inhibition of [3H]thymidine incorporation), but did not cause cell lysis. Mitochondrial respiration inhibition activity was not detected in CS until 4 hr; it reached a maximum at 18 hr and declined rapidly by 24 hr. EMT-6 cells recovered from inhibition if the CS was removed from culture, but no recovery was observed if the target cells were in continuous exposure to CS for 72 hr. Fractionation of CS by using a molecular exclusion column of Sephacryl S-200 resulted in the recovery of two peaks that showed respiration inhibitory activity. These peaks, eluting at 55,000 and 80,000 daltons, mediated the inhibition of malate and succinate oxidation and were cytostatic for EMT-6 cells.
Cyclosporine therapy of rat heart allograft recipients and release of interleukins (IL 1, IL 2, IL 3): a role for IL 3 in graft tolerance?
Authors: Abbud-Filho M , Kupiec-Weglinski J W , Araujo J L , Heidecke C D , Tilney N L , Strom T B 
Published: December 2022

Abstract
LEW rat recipients of (LEW X BN)F1 strain heterotopic cardiac transplants treated with cyclosporine A (CsA) (15 mg/kg/day intramuscularly, 7 days) retain grafts indefinitely despite drug withdrawal. Donor-specific suppressor T cells that are active in passive transfer experiments have been harvested from long-term CsA-treated hosts. Although CsA is known to inhibit in vitro cytokine release, the in vivo effects of the CsA on the lymphokine cascade are not known. We investigated the action of the drug upon spontaneous and mitogen-induced interleukin 1 (IL 1), interleukin 2 (IL 2), and interleukin 3 (IL 3) release by spleen cells obtained from the following groups of rats: 1) normal, i.e., untreated and ungrafted; 2) grafted, acutely rejecting; 3) grafted, actively treated; and 4) under CsA-induced state of "tolerance." The results demonstrate that in vivo CsA therapy inhibits monocyte (IL 1 release) as well as lymphocyte function (IL 2 and IL 3 release) only during the inductive phase (the 7 days of treatment). During the "tolerant" phase, mitogen (Con A and LPS)-induced release of interleukins was quantitatively similar to that noted in normal animals. In contrast, a remarkable increase in the spontaneous production of IL 3 was observed in the "tolerant" group. Because cytokine release is not inhibited in the "tolerant" state, our data strongly support the concept that maintenance of the state of unresponsiveness is governed by the emergence of suppressor cells. The correlation of increased spontaneous production of IL 3 during this period leads us to postulate that this interleukin may be implicated in the activation or clonal expansion of suppressor cells, and hence may play a role in graft tolerance.
Idiotypic analysis of anti-I-Ak monoclonal antibodies. I. Production and characterization of syngeneic anti-idiotypic mAb against an anti-I-Ak mAb.
Authors: Phillips M L , Harris J F , Delovitch T L 
Published: December 2022

Abstract
To analyze the idiotype (Id) of anti-Ia antibodies elicited during alloimmune responses, we produced syngeneic mouse anti-Id monoclonal antibodies (mAb) reactive with the Id of the 11-5.2.1.9 (11-5) mouse anti-I-Ak (BALB/c anti-CKB) mAb. Two such anti-Id mAb, IA2 (IgG2a) and IIID1 (IgG1), detect structurally related idiotopes located within the binding site of 11-5 for I-Ak antigens. A third anti-Id mAb, VC6 (IgG1), detects an idiotope located either inside or outside of, but presumably proximal to, the 11-5 antigen-binding site, because its expression correlates with the antigenic specificity of 11-5. None of the idiotopes detectable by these three anti-Id mAb are accessible when the binding site of 11-5 is occupied by an I-Ak molecule. The association constants of these anti-Id mAb for their cognate Fab-linked Id range from 2 X 10(9) to 1 X 10(10) M-1. The three anti-Id-producing hybridomas were found with a frequency of 0.008% among growing hybrid colonies. Even though these anti-Id mAb detect public idiotopes (IdX) on 11-5, they do not detect the presence of such IdX markers in the sera of five syngeneic BALB/c mice hyperimmunized with C3H (I-Ak) spleen cells. This suggests that 11-5 represents a BALB/c idiotype infrequently expressed by serum immunoglobulins. The 11-5 idiotopes detectable by IA2, IIID1, and VC6 seem to be conformationally determined by the interaction of 11-5 H and L chains and are not confined to one or the other of these subunit polypeptides. Thus, the expression of the 11-5 Id may be regulated by both VH and VL genes.
Estradiol regulation of secretory component in the uterus of the rat: evidence for involvement of RNA synthesis.
Authors: Wira C R , Stern J E , Colby E 
Published: December 2022

Abstract
The present studies were undertaken to characterize the response of uterine secretory component (SC) to estradiol. Administration of estradiol for 3 days to ovariectomized rats before incubation of uterine tissues resulted in a marked accumulation of SC in the incubation media. When uteri from ovariectomized rats treated with progesterone or testosterone were incubated, very little SC accumulated in the media, indicating that the estradiol-stimulated increase is hormone-specific. When uteri from rats that received estradiol for 6 days were compared with uteri from 3-day treated rats, SC release during a 24-hr incubation period was the same. This finding indicates that in the presence of prolonged estradiol exposure, SC production continues. The estradiol-induced accumulation of SC in culture is not due to the release of pre-formed uterine SC. When tissue SC levels were measured after 3 days of estradiol treatment, very little tissue SC was found relative to that released into culture media during 24 hr of incubation. The addition of actinomycin D to the incubation media markedly inhibited SC release by uteri from estradiol-treated rats. The release of SC was also inhibited by alpha-amanitin, a known inhibitor of Type II polymerase. These studies demonstrate that estradiol stimulation of SC is markedly reduced by inhibitors of RNA synthesis, and suggest that estradiol regulation of SC is mediated through uterine mRNA synthesis.
Rodgers (Rg) and Chido (Ch) determinants on human C4: characterization of two C4 B5 subtypes, one of which contains Rg and Ch determinants.
Authors: Roos M H , Giles C M , Demant P , Mollenhauer E , Rittner C 
Published: December 2022

Abstract
The genetically determined polymorphism of the fourth component of human complement was further extended with the aid of a panel of human allo-anti-C4 sera, anti-Rodgers and anti-Chido. These antisera were found previously to react with the alpha-chains of the C4 molecules controlled by the C4A and C4B loci, respectively. We analyzed a number of new and rare C4 allotypes, and found that they generally followed the expected pattern. Some interesting exceptions, however, were found. The alpha-chain of the allotype C4A1 was found to react with anti-Chido, unlike all other C4A allotypes. Also the C4B5 allotype could be subdivided into two subtypes on the basis of their reaction with anti-Rodgers. They were tentatively named B5Rg+ and B5Rg-. Moreover, the B5Rg+ subtype reacted not only with anti-Rodgers but also with some anti-Chido sera, indicating for the first time that Chido and Rodgers determinants are present on the same allotype.
Inhibition of proliferation of mouse T cell-dependent bone marrow-derived mast cells by rat serum does not change their unique phenotype.
Authors: Stevens R L , Bloes W F , Seldin D C , Razin E , Katz H R , Austen K F 
Published: December 2022

Abstract
Both mouse and rat sera have been found to inhibit proliferation in vitro of interleukin 3-dependent chondroitin sulfate E proteoglycan-containing mouse bone marrow-derived mast cells (BMMC), as assessed by quantitation of 3H-labeled thymidine incorporation into DNA, cell cycle analysis, and cell number. Rat serum (9%) inhibited 3H-labeled thymidine incorporation within 60 min of exposure in a culture medium composed of 1% fetal calf serum (FCS) and 16% concanavalin A splenocyte-conditioned medium. The anti-proliferative effect of rat serum did not alter cell viability for 17 hr of subsequent culture, was dose related, with a maximal effect at 7% rat serum, and was reversible. Cytofluorographic analysis of relative DNA content per cell revealed that the proportion of cells in the S + G2 + M phases of the cell cycle was decreased in cells treated with 9% rat serum compared with cells cultured in either 1% or 10% FCS. These rat serum-treated BMMC exhibited no change in plasma membrane antigen phenotype as assessed by 15 monoclonal antibodies, and continued to synthesize chondroitin sulfate E proteoglycan. When sensitized with monoclonal IgE antibody, washed, and challenged with specific antigen, the rat serum-treated BMMC released the preformed secretory granule-associated mediators beta-hexosaminidase and histamine, and the newly generated lipid mediators leukotriene C4 (LTC4) and leukotriene B4 (LTB4) in amounts comparable to BMMC cultured in 10% FCS. Thus, the unique cell surface phenotype, the presence of chondroitin sulfate E proteoglycan rather than heparin proteoglycan, and the generation of LTC4 and LTB4 in a ratio of approximately 6:1 upon perturbation of the IgE receptor are distinctive characteristics of the interleukin 3-dependent mouse BMMC subclass, and not a functional consequence of the rapid proliferation of the cell.
Pharmacologic effects on mouse isolated atria of immunoglobulins directed against class I histocompatibility antigens.
Authors: Cremaschi G A , Sterin-Borda L , Genaro A M , Borda E S , Braun M 
Published: December 2022

Abstract
Sera from alloimmunized mice exert potent inotropic and chronotropic effects on mouse isolated atria. In this report, we present data showing that both total immunoglobulins and purified IgG from alloimmunized mice were able to exert per se these effects. The pharmacologic effects of IgG were parallel to its cytotoxic titer but not to its immunofluorescence titer. The specificity of the inotropic and chronotropic effects was studied by using several interstrain immunizations and target atria. It was observed that only the sera from mice immunized with H-2-disparate cells were able to exert pharmacologic effects on atria; these effects were evident not only on atria from the immunizing strain, but also on atria from other strains having identical H-2 but different backgrounds. Neither normal sera nor sera from animals immunized against non-H-2 differences were active. The effect of sera, total immunoglobulins, and purified IgG were blocked by propranolol, suggesting the involvement of beta-adrenoreceptor in the reaction.
Inhibition of macrophage C3b-mediated ingestion by syphilitic hamster T cell-enriched fractions.
Authors: Tabor D R , Azadegan A A , Schell R F , Lefrock J L 
Published: December 2022

Abstract
Macrophages are important for host defense against syphilitic infection. Our results show that C3b-mediated ingestion (C3bMI), a characteristic of activated macrophages, was inhibited in vitro by nonadherent cells from hamsters infected with Treponema pallidum subspecies endemicum. When macrophage target cells from normal, syphilitic, or lipopolysaccharide-treated animals were co-cultured with nonadherent cells derived from normal or syphilitic hamsters, noticeable differences were detected. Nonadherent syphilitic cells significantly suppressed macrophage C3bMI, whereas normal nonadherent cells displayed little or no suppressive activity. In general, macrophage C3bMI was reduced by nonadherent cells obtained throughout the course of syphilitic infection, although it eventually began to recover. The syphilitic nonadherent cells with maximum suppressive effect were those obtained from hamsters infected for 3 to 6 wk. The addition of treponemal antigens additionally inhibited C3bMI. The inhibitory effect of syphilitic nonadherent cells on either lipopolysaccharide-treated or syphilitic macrophages was sustained even when the nonadherent cells were removed from the cultures, and the effect continued for at least 72 hr thereafter. Fractionation of syphilitic nonadherent cell populations by two independent methods produced T cell-enriched preparations with significantly more suppressive activity than non-T cell-enriched preparations. These observations may account for the chronicity of syphilitic infection.
Human cytotoxic T cell clones directed against herpes simplex virus-infected cells. II. Bifunctional clones with cytotoxic and virus-induced proliferative activities exhibit herpes simplex virus type 1 and 2 specific or type common reactivities.
Authors: Yasukawa M , Zarling J M 
Published: December 2022

Abstract
Human cytotoxic T lymphocyte (CTL) clones directed against herpes simplex virus (HSV)-infected cells were generated after stimulation of peripheral blood lymphocytes (PBL) with HSV type 1 (HSV-1) and HSV type 2 (HSV-2). These CTL clones were studied with regard to HSV type specificity and with regard to whether they also express helper cell activity. Some clones, generated after stimulation with HSV-1, were cytotoxic for autologous cells infected with either HSV-1 or HSV-2 ("HSV type common clones"), whereas other clones lysed HSV-1-infected cells only ("type-specific clones"). Similarly, after HSV-2 stimulation, both HSV-2 specific and HSV type common clones were obtained, indicating the heterogeneity of human cytotoxic T cells to HSV. All CTL clones tested were found to be bifunctional in that they also proliferated in response to stimulation with HSV. The HSV type specificity of the proliferative response was identical to that of the cytotoxic activity of the clones. An HSV type common clone, when stimulated with either HSV-1 or HSV-2, and an HSV-1 specific clone, when stimulated with HSV-1 but not with HSV-2, produced a factor, presumably interleukin 2 (IL 2), which induced proliferation of CTLL, an IL 2-dependent T cell line, providing evidence that our HSV-directed CTL clones also express helper cell activity. CTL clones that we previously reported were restricted in cytotoxic activity by HLA class II DR-1 or MB-1 antigens were found, in this study, to be restricted in proliferative response to HSV by these same HLA antigens. These results suggest that our bifunctional T cell clones directed against HSV may recognize the same viral antigenic determinants and the same HLA antigens for both cytotoxic and virus-induced proliferative activities. This is the first demonstration of human HSV type specific and HSV type common T cell clones and HSV specific T cell clones with both cytotoxic and helper cell activities.
T cell responses to cleaved rabies virus glycoprotein and to synthetic peptides.
Authors: Macfarlan R I , Dietzschold B , Wiktor T J , Kiel M , Houghten R , Lerner R A , Sutcliffe J G , Koprowski H 
Published: December 2022

Abstract
The antigenic structure of the rabies virus glycoprotein has been studied. A limited number of fragments were obtained by cyanogen bromide (CNBr) cleavage of viral glycoprotein, and eight large peptides were isolated by using sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. These were tested for their capacity to stimulate the proliferation of nylon wool-purified T cells obtained from spleens of rabies-immune A/J mice. Three peptides (Cr1, Cr2 plus Cr2A, and Cr3) stimulated antigen-specific proliferation, indicating that at least three T cell determinants of the native molecule are sequential or continuous in nature. Stimulation was also obtained with 27-residue and 13-residue synthetic peptides (designated R21 and R20, respectively) that included sequences towards the carboxy terminal end of Cr1, but not with synthetic peptides that included sequences of Cr2 and Cr3 (which are both glycosylated in virus-derived material). The intact viral glycoprotein and synthetic peptide R21 stimulated T lymphocytes with surface characteristics of helper cells, and induced the production of interleukin 2 by these lymphocytes. Synthetic peptides R20 and R21 also stimulated a minor population of Lyt-2-positive cells, which were not yet identified as either suppressor or cytotoxic T lymphocytes.
Sex and H-2 haplotype control the resistance of CBA-BALB hybrids to the induction of T cell lymphoma by Moloney leukemia virus.
Authors: Storch T G , Chused T M 
Published: December 2022

Abstract
CBA/N and CBA/CaHN have a significantly longer latent period than other inbred mouse strains between infection with Moloney murine leukemia virus and the appearance of T cell lymphoma. The genetic characteristics of this resistance have been analyzed in the F1 hybrids of CBA/N and CBA/CaHN with BALB H-2 congenic strains. Sexual phenotype and H-2 haplotype significantly influenced survival in the F1 hybrids of CBA/CaHN with BALB. In the F1 with BALB/cJ and BALB/cAnN (both H-2d), the males survived significantly longer than the females; but in the F1 with BALB.K (H-2k) and BALB.B (H-2b), the survival of males and females was the same. Survival was not prolonged by the recessive X-linked immunodeficiency gene xid or other genes on the CBA/N X-chromosome, because the (CBA/N X BALB/c)F1 male and the reciprocal (BALB/c X CBA/N)F1 male, which does not carry the CBA X-chromosome, were equally resistant. H-2 haplotype did not influence survival among the BALB H-2 congenics, and sex had little effect on the resistance of the CBA and BALB parents. These results demonstrate that a sex-dependent gene linked to H-2 significantly influences the expression of CBA genes for lymphoma resistance in the F1 hybrid with BALB.
Effects of ultraviolet radiation on human epidermal cell alloantigen presentation: initial depression of Langerhans cell-dependent function is followed by the appearance of T6- Dr+ cells that enhance epidermal alloantigen presentation.
Authors: Cooper K D , Fox P , Neises G , Katz S I 
Published: December 2022

Abstract
The effects of ultraviolet radiation (UV) on the immune parameters of human epidermis were studied. We determined the effects of both in vitro and in vivo UV on human epidermal cell surface markers and on epidermal immune function in the allogeneic epidermal cell-lymphocyte reaction (ELR). Epidermal cells obtained immediately after in vitro and in vivo UV exposure exhibited a dose-dependent decrease in alloantigen-presenting function in the ELR. This was not the result of a decrease in the number of T6+ Dr+ Langerhans cells but was due to their being less efficient at alloantigen presentation than equivalent numbers of Langerhans cells from unirradiated skin. The reduced stimulation in the ELR immediately after UV was not reversible by the addition of exogenous IL 1 or indomethacin and thus appeared to be due to a direct effect of UV on the alloantigen-presenting function of Langerhans cells. In contrast to this suppression of the epidermal immune function when epidermal cells were obtained immediately after UV, epidermal cells harvested 24 hr or later after in vivo UV exhibited a dose-dependent enhancement of allostimulatory capacity in the ELR that peaked 3 days after UV. The time course of the enhancement of allostimulation in the ELR after in vivo UV coincided with a decrease in the percentage of Langerhans cells and the appearance within the epidermis of T6- Dr+ cells, which are derived from the bone marrow, as evidenced by their expression of the bone marrow derivation markers HLe 1 and T200. Removal of Dr+ cells but not of T6+ cells from epidermal cell suspensions harvested 3 days after in vivo UV abrogated allostimulation in the ELR, demonstrating that the T6- Dr+ cells were responsible for the observed UV-induced enhancement of alloantigen presentation. Taken together, the results indicate that the timing and dosage of UV exposure are critical factors determining whether suppression or enhancement of epidermal immune function follows UV.
Defective IFN-gamma production in the human neonate. II. Role of increased sensitivity to the suppressive effects of prostaglandin E.
Authors: Wakasugi N , Virelizier J L , Arenzana-Seisdedos F , Rothhut B , Huerta J M , Russo-Marie F , Fiers W 
Published: December 2022

Abstract
Analysis of endogenous production and effects of exogenous addition of interleukin 2 (IL 2), leukotrienes (LT), and prostaglandin E (PGE) has been used to investigate the dysregulation responsible for impaired PHA-induced IFN-gamma secretion by cord blood leukocytes (CBL). The addition of LT or IL 2 could not reverse the IFN defect of CBL. The production of these two mediators was found to be normal in CBL cultures. CBL and control leukocytes from adult donors produced comparable amounts of PGE2. In contrast, sensitivity to the suppressive effects of PGE2 on IFN-gamma secretion was much higher with CBL than with control leukocytes. Treatment with indomethacin reversed the IFN-gamma defect with most CBL tested, and the addition of physiologic amounts of PGE2 to indomethacin-treated cultures resulted in a profound impairment of IFN-gamma production similar to that of untreated CBL cultures. Preincubation of CBL for 24 hr before PHA stimulation resulted in restoration of a normal sensitivity to exogenous PGE2, in parallel with correction of the IFN-gamma defect. Our observations suggest that the impairment of IFN-gamma secretion in neonates is not due to deficient amplification circuits, but is the consequence of an exaggerated cellular sensitivity to the suppressive effects of PGE produced endogenously in normal amounts.
Potential Z-DNA-forming elements in serum DNA from human systemic lupus erythematosus.
Authors: Van Helden P D 
Published: December 2022

Abstract
DNA fragments were isolated from serum of a patient with systemic lupus erythematosus. The majority of the DNA was between 150 and 250 base pairs in length. The DNA was cloned into phage M13, and 10 recombinants were sequenced. The average GC content of the DNA was higher than total human DNA (43% against 38%), with some fragments as high as 63%. This DNA is rich in alternating purine-pyrimidine segments that are potentially Z-DNA-forming regions.