bluuebunny/crossref_metadata_2025_split huggingface dataset:
Procyclic tsetse fly midgut forms and culture forms of African trypanosomes share stage- and species-specific surface antigens identified by monoclonal antibodies.
Authors: Richardson J P , Jenni L , Beecroft R P , Pearson T W 
Published: January 2023

Abstract
Procyclic culture form (PCF) trypanosomes were established from a bloodstream form population of cloned Trypanosoma brucei rhodesiense and were used to immunize mice for hybridoma production. Indirect immunofluorescence was used to select 10 hybridomas which secreted antibodies that bound to the surface of homologous living PCF. The antibodies reacted with PCF of several clones of T.b. brucei, T.b. gambiense, and T.b. rhodesiense, but not with PCF of T. congolense or T. vivax, or with promastigotes of several species of Leishmania parasites. The antigens were not detectable in ethanol/acetic acid-fixed bloodstream forms or in lysates of bloodstream forms of any of the T. brucei subspecies, and are thus species-specific and stage-specific markers. Selected monoclonal antibodies bound to procyclic trypanosomes taken directly from the midgut of infected tsetse flies, and to immature epimastigote forms in salivary probes, and may therefore be useful in epidemiologic investigations.
Activation of complement by pathogenic and nonpathogenic Entamoeba histolytica.
Authors: Reed S L , Curd J G , Gigli I , Gillin F D , Braude A I 
Published: January 2023

Abstract
Previous studies had demonstrated that strains of Entamoeba histolytica isolated from patients with colitis or amebic liver abscess were resistant to complement-mediated killing, whereas strains from asymptomatic patients were readily lysed by non-immune serum. Both serum-sensitive and serum-resistant strains of E. histolytica depleted complement rapidly as assessed by CH50, C3, and C7, and C5-9 hemolytic activities. Activation of the alternative pathway was important in lysis of nonpathogenic strains, as demonstrated by lysis by NHS (60.9 +/- 15.6%) and NHS + 5 mM EGTA (59.3 +/- 4.5%) as well as by C4-deficient guinea pig serum (72.8 +/- 7.1%) and C2-deficient human serum (64.4 +/- 11.1%), but not by NHS + 5 mM EDTA. Classical pathway activation also occurs as both pathogenic and nonpathogenic strains deplete greater than 98% of C4 activity, although it is not necessary for lysis. Pathogenic strains are not lysed by either the classical or the alternative pathway. These results suggest that pathogenic strains of E. histolytica activate complement but are able to evade an important host defense, complement-mediated lysis.
The activation of tumoricidal properties in human blood monocytes by muramyl dipeptide requires specific intracellular interaction.
Authors: Fogler W E , Fidler I J 
Published: January 2023

Abstract
The purpose of this study was to identify the mechanism by which muramyl dipeptide (MDP) activates antitumor cytotoxic properties in normal and interferon-gamma (IFN-gamma)-primed human peripheral blood monocytes. The structurally and functionally active MDP analog, nor-muramyl dipeptide (nor-MDP), and [3H]nor-MDP were used as reference glycopeptides. Direct activation of normal, noncytotoxic monocytes by nor-MDP was enhanced by its encapsulation within multilamellar vesicles (MLV). Studies with [3H]nor-MDP revealed that the activation of monocytes by nor-MDP was not attributable to its interaction with a specific cell surface receptor, nor did it result merely from the internalization by monocytes of glycopeptide. Subthreshold concentrations of nor-MDP could activate tumor cytotoxic properties in IFN-gamma-primed monocytes. The intracellular interaction of [3H]nor-MDP with IFN-gamma-primed monocytes was specific in that intracellular levels of radiolabeled material could be displaced and recovered as intact molecules by unlabeled nor-MDP, but not by a biologically inactive MDP stereoisomer. Collectively, these results suggest that the activation of tumoricidal properties in human blood monocytes by MDP occurs subsequent to intracellular interaction with specific MDP receptors.
The monoclonal antibody CJA3 down-regulates the susceptibility of human tumor cell lines to natural cell-mediated cytotoxicity.
Authors: Allen J I , Ferrone S , Boue D , Kay N E 
Published: January 2023

Abstract
While developing monoclonal antibodies (MoAb) to colorectal carcinoma (CRC) cells, we noted that one MoAb, termed CJA3, down-regulated natural cell-mediated cytotoxicity (NCMC) against CRC cell lines SW480 and SW620. The MoAb CJA3 was developed by immunizing a BALB/c mouse with fresh human colorectal adenocarcinoma cells. The antigen recognized by the MoAb CJA3 was expressed on several solid tumor cell lines and on one of the six lymphoreticular cell lines tested, but was not detected on normal peripheral blood lymphocytes (PBL). SDS-PAGE analysis of the antigen immunoprecipitated by the MoAb CJA3 from the CRC cell lines SW480 and SW620 and from the melanoma cell line MALME-3M revealed a component with a m.w. of 150,000. Preincubation of CRC cell lines SW480 and SW620 with the MoAb CJA3 for 16 hr reduced their susceptibility to NCMC by about 50%. Kinetic experiments showed that prolongation of the incubation of target cells with the MoAb CJA3 resulted in a time-dependent increase in the amount of MoAb bound. Maximum binding of the MoAb CJA3 was reached after 4 hr of incubation. The increase in antigen expression chronologically paralleled the decrease in NCMC target cell sensitivity, suggesting that the membrane alterations induced by the MoAb CJA3 were important for NCMC against these two cell lines.
Autoimmune thyroiditis induced in mice depleted of particular T cell subsets. I. Requirement of Lyt-1 dull L3T4 bright normal T cells for the induction of thyroiditis.
Authors: Sugihara S , Izumi Y , Yoshioka T , Yagi H , Tsujimura T , Tarutani O , Kohno Y , Murakami S , Hamaoka T , Fujiwara H 
Published: January 2023

Abstract
T cell-depleted C3H/He or (C57BL/6xC3H/He)F1 (B6C3F1) mice were prepared by adult thymectomy and injection of antithymocyte serum, followed 3 wk later by lethal x-irradiation and bone marrow reconstitution. When these T cell-depleted mice were not injected or injected i.v. with normal spleen and lymph node cells treated with either anti-Thy-1, -L3T4 or -Lyt-2 antibody plus C or C alone, none of the groups of mice developed thyroiditis. In contrast, the adoptive transfer of normal cells treated with anti-Lyt-1 plus C resulted in high incidence of the production of antithyroglobulin antibody and the induction of typical thyroiditis lesion. The thyroid was the sole organ involved, because neither typical inflammatory lesion in other organs nor autoantibody such as anti-DNA antibody was detected in mice that exhibited thyroiditis. Analyses of surface phenotypes of cells required for inducing thyroiditis by the adoptive transfer revealed that an appreciable percentage of Lyt-1 dull T cells remained after the treatment of normal lymphoid cells with anti-Lyt-1 plus C. Almost all of these Lyt-1 dull T cells expressed magnitudes of L3T4 or Lyt-2 Ag comparable to those detected on Lyt-1 bright T cells. More important, the induction of thyroiditis was almost completely prevented by either in vitro or in vivo elimination of Lyt-1 dull L3T4+(bright) but not of Lyt-1 dull Lyt-2+(bright) T cells. These results indicate that Lyt-1 dull L3T4+ T cells existing in normal healthy individuals have potential to induce typical thyroiditis which is associated with the production of antithyroglobulin autoantibody, and that the activation and/or function of this T cell subset is regulated by the Lyt-1 bright T cell population coexisting in normal lymphoid cell population.
Restricted heterogeneity of antibody to gp120 and p24 in AIDS.
Authors: Grimaldi L M , Roos R P , Devare S G , Robey W G , Casey J M , Gurney M E , Apatoff B R , Lazzarin D 
Published: January 2023

Abstract
Neurologic complications and cerebrospinal fluid (CSF) abnormalities are common in AIDS. We found that a substantial number of AIDS patients with neurologic involvement had oligoclonal IgG bands in CSF and sera by IEF. Using an IEF-Ag overlay technique, anti-gp120 antibody activity was demonstrated more frequently than anti-p24 antibody activity. These antibody activities exhibited restricted heterogeneity of their IEF pattern; this restriction may contribute to the relatively low titers of neutralizing antibody found in AIDS sera. None of the CSF and serum oligoclonal bands showed anti-HIV antibody activity, suggesting that they are directed against opportunistic agents or result from immunodysregulation.
Novel and enhanced IL-1 gene expression in autoimmune mice with lupus.
Authors: Boswell J M , Yui M A , Endres S , Burt D W , Kelley V E 
Published: January 2023

Abstract
IL-1 is a pleiotropic factor encoded for by at least two genes, alpha and beta, and capable of eliciting a broad set of immunologic and inflammatory events. MRL/MP-lpr (MRL-lpr) mice are an appealing model for studies of renal injury inasmuch as disease in this strain is spontaneous, rapid, predictable, and regulated by the lpr gene. Infiltration of macrophages and the proliferation of the glomerular mesangial cells are prominent features of renal disease. Because both mesangial cells and macrophages can synthesize IL-1, the purpose of this study was to determine whether enhanced IL-1 gene expression is associated with lupus nephritis in the MRL-lpr mouse model. Glomerular macrophages, abundant in the kidneys of MRL-lpr mice but rarely present in the kidney of congenic MRL/MP-++(MRL-++) mice, were isolated and cultured and found to express a 10-fold increase in both IL-1 alpha and IL-1 beta mRNA transcripts as compared with MRL-++ and MRL-lpr mesangial cells. IL-1 alpha was not detected in the total RNA extracted from freshly excised kidney, whereas IL-1 beta transcripts were detected in both the renal cortex of MRL-lpr as well as MRL-++ animals. A previously undetected truncated 1200 nucleotide IL-1 beta transcript together with the conventional 1600 nucleotide IL-1 beta transcript was found in kidneys from MRL-lpr and was abundantly expressed in glomeruli of MRL-lpr mice with lupus nephritis. Isolated glomeruli from MRL-lpr mice with nephritis produce IL-1, whereas in normal glomeruli from MRL-++ and C3H/FeJ mice this cytokine was not detected. Glomerular macrophages and mesangial cells cultured from MRL-lpr mice with nephritis both secrete IL-1. These studies indicate that IL-1 beta gene expression and IL-1 protein are increased in the kidneys of autoimmune mice with lupus nephritis and is generated, at least in part, by glomerular macrophages. We speculate that an alteration in IL-1 beta gene expression may be responsible for causing a cascade of events leading to acute and chronic renal injury.
Increased resistance to non-MHC-restricted cytotoxicity related to HLA A, B expression. Direct demonstration using beta 2-microglobulin-transfected Daudi cells.
Authors: Quillet A , Presse F , Marchiol-Fournigault C , Harel-Bellan A , Benbunan M , Ploegh H , Fradelizi D 
Published: January 2023

Abstract
Experiments in several laboratories have shown that target susceptibility to NK and lymphokine-activated killer (LAK) cytotoxicity is inversely correlated with the target expression of HLA Class I molecules. We present the first direct evidence, obtained by gene transfection, that target cell HLA, A, B expression increases the resistance to the "so-called" non-MHC-restricted cytotoxicity. We have co-transfected, by electroporation, the human beta 2-microglobulin gene and the gene carrying the resistance to geneticin into Daudi cell line. Geneticin selection in culture followed by FACS sorting on the basis of strong positivity with the mAb W6/32 (which is specific for the HLA class I H chain associated to beta 2-microglobulin) have led to the establishment of a HLA+ Daudi cell line permanently expressing HLA A10, A11, and B17 molecules. Studies were performed in vitro to evaluate the susceptibility of these cells to either NK and LAK cytotoxicity. The HLA class I+ Daudi cells exhibit an increased resistance to killing by non-MHC-restricted killer cells (both NK and LAK) as compared with their HLA-Daudi counterpart.
Differential regulation of gene expression during macrophage activation with a polyribonucleotide. The role of endogenously derived IFN.
Authors: Riches D W , Henson P M , Remigio L K , Catterall J F , Strunk R C 
Published: January 2023

Abstract
The activation of macrophages by exposure to the polyribonucleotide, poly [I:C], is accompanied by a large stimulation of the synthesis of the C components factor B and C3, and a concomitant inhibition of the synthesis of the lysosomal enzyme beta-glucuronidase. Northern blot analysis of poly [A+] RNA extracted from poly [I:C]-stimulated cells revealed that the changes in the synthesis of factor B and C3 were related to changes in the levels of their respective mRNA and hence the expression of these proteins appeared to be regulated at a pre-translational level. The down-regulation of the synthesis of beta-glucuronidase appeared to be regulated at both translational and pre-translational levels. In view of the proposed role of macrophage-derived IFN in the regulation of macrophage activation, we investigated the possible role of IFN-alpha/beta in the regulation of the synthesis of factor B, C3, and beta-glucuronidase. Exposure of macrophages to mouse IFN-alpha and IFN-beta induced limited changes in the synthesis of factor B, C3, and beta-glucuronidase. However, pretreatment of macrophages with only 500 U/ml of IFN-beta primed the cells thereby increasing their sensitivity to poly [I:C]. IFN-alpha was less effective as a priming agent. When macrophages were exposed to poly [I:C] in the presence of an anti-mouse IFN-alpha/beta antiserum, the changes in the synthesis of factor B, C3, and beta-glucuronidase were partially inhibited. Collectively, these data indicate first, that exposure of mouse bone marrow-derived macrophages to poly [I:C] differentially regulates the expression of the products of the genes for factor B, C3, and beta-glucuronidase. Second, IFN-alpha and IFN-beta prime macrophages to increase the sensitivity of macrophages to poly [I:C]. Third, in the absence of exogenous IFN, macrophage-derived IFN appears to participate in priming the cells in an autocrine or paracrine fashion.
Role of asialo-GM1-positive lymphoid cells in mediating the toxic effects of recombinant IL-2 in mice.
Authors: Gately M K , Anderson T D , Hayes T J 
Published: January 2023

Abstract
Studies were performed to characterize the toxic effects of human rIL-2 in mice and to examine the mechanism of toxicity. Intraperitoneal administration of rIL-2 at doses greater than or equal to 2 X 10(6) U/kg twice each day for greater than or equal to 4 days led to toxicity in several strains of mice. The toxic effects of rIL-2 included the vascular leak syndrome (manifested by pulmonary edema, pleural effusions, and ascites), elevated hepatic transaminases, hyperbilirubinemia, hypoalbuminemia, pre-renal azotemia, anemia, thrombocytopenia, mild eosinophilia, and death. Marked lymphoid cell infiltration of pulmonary and hepatic vasculature was present in mice suffering from rIL-2 toxicity, and the pleural and ascitic fluids also contained high numbers of mononuclear cells. Mononuclear cells isolated from the pleural fluids and livers of these mice were 74 to 98% Thy-1+, 55 to 83% asialo-GM1+, 29 to 45% Lyt-2+, and less than 10% L3T4+. These cells possessed potent lymphokine-activated killer (LAK)-like activity in that their ability to lyse cells of the NK-resistant P815 mastocytoma line was 10- to 100-fold higher on a per cell basis than splenocytes from the same animals. A correlation was found between the dose level, duration, and frequency of dosing with rIL-2 required to induce pleural effusions and hepatotoxicity and the dosage regimens required to produce the LAK-like cells in the pleural cavities and livers, respectively, of rIL-2-treated mice. Moreover, treatment of mice with anti-asialo-GM1 (anti-ASGM-1) antiserum in vivo at the same time they were receiving toxic doses of rIL-2 abolished or greatly reduced the severity of the vascular leak syndrome and hepatotoxicity and significantly prolonged the survival of the mice. Administration of anti-ASGM-1 to mice receiving toxic doses of rIL-2 resulted in a marked reduction in the LAK-like cytolytic activity of their pleural and liver lymphoid cells and a corresponding reduction in the percentage of ASGM-1+ cells in pulmonary and hepatic lymphoid infiltrates. Nevertheless, the overall extent of pulmonary and hepatic lymphoid infiltration, as well as other consequences of rIL-2 administration, including splenomegaly, hypoalbuminemia, eosinophilia, and thrombocytopenia, were not diminished as a result of anti-ASGM-1 treatment.(ABSTRACT TRUNCATED AT 400 WORDS)
Enhancement of release of granulocyte- and granulocyte-macrophage colony-stimulating factors from phytohemagglutinin-stimulated sorted subsets of human T lymphocytes by recombinant human tumor necrosis factor-alpha. Synergism with recombinant human IFN-gamma.
Authors: Lu L , Srour E F , Warren D J , Walker D , Graham C D , Walker E B , Jansen J , Broxmeyer H E 
Published: January 2023

Abstract
The influence of purified recombinant human TNF-alpha (rhuTNF-alpha) was assessed, alone and in combination with purified recombinant human IFN-gamma (rhuIFN-gamma), for its effects on enhancing release from human T lymphocytes of activities that stimulate colony formation by granulocyte-macrophage, erythroid, and multipotential progenitor cells. rhuTNF-alpha or rhuIFN-gamma enhanced the release of CSF, which were determined to be granulocyte-CSF and granulocyte-macrophage-CSF by human bone marrow colony assays, morphologic assessment of colony types, and neutralization studies with rabbit anti-human granulocyte-CSF and monoclonal mouse anti-human granulocyte-macrophage-CSF. The CSF were released only when PHA was used, whether or not rhuTNF-alpha and/or rhuIFN-gamma were present while the lymphocytes conditioned the medium. T lymphocytes were sorted into subsets by using three-color immunofluorescence and a dye laser flow cytometry system with cells incubated with biotin anti-Leu-4 labeled with Texas Red, FITC-conjugated anti-Leu-3a, and phycoerythrin-conjugated anti-Leu-2a. Both the Leu-4+3a+2a- and the Leu-4+2a+3a- cells released CSF in response to PHA, but the release of CSF from PHA-stimulated lymphocytes was enhanced by rhuTNF-alpha and rhuIFN-gamma only from the Leu-4+3a+2a- subset of cells. Use of the three-color cell sorting made it highly unlikely that NK cells were involved, because both sorted subsets were positive for Leu-4. rhuTNF-alpha and rhuIFN-gamma synergized to enhance release of CSF such that low concentrations of each molecule, which were inactive when used alone, were active when the two molecules were used together. These studies suggest a role, at least in vitro, for TNF-alpha and IFN-gamma in the release of CSF from subsets of T lymphocytes stimulated with PHA.
Characteristics and mechanism of neutrophil-mediated cytostasis induced by tumor necrosis factor.
Authors: Shau H 
Published: January 2023

Abstract
After being treated with rTNF, polymorphonuclear neutrophils (PMN) were highly suppressive to the growth of four different tumor target cells, Raji, K562, UCLA-SO-M14, and U937. Neutralizing TNF with specific antibodies before PMN were treated blocked induction of the anti-proliferative activity against Raji. However, after PMN were exposed to TNF the cytostatic activity could not be reversed by the antibody or by washing off TNF, indicating that the continuous presence of TNF was not required for expression of the anti-proliferative function. Addition of the hydrogen peroxide (HP) scavenger, catalase, at the beginning of the assay inhibited the cytostatic activity, suggesting that HP was involved in suppressing the tumor cell growth. In contrast, other reactive oxygen species inhibitors such as superoxide dismutase, sodium azide, L-methionine, or deferoxamine did not inhibit the cytostasis. HP alone at above 10 microM was cytostatic to Raji cells. The presence of TNF did not increase the sensitivity of Raji to HP. TNF activated PMN to produce HP but the amount of HP released in the culture supernatant was too low for direct cytostasis. PMN also became more adherent after TNF treatment. Therefore, the TNF-induced cytostasis may be mediated by local high concentrations of HP produced by PMN.
Immunoregulation in murine malaria. Susceptibility of inbred mice to infection with Plasmodium yoelii depends on the dynamic interplay of host and parasite genes.
Authors: Sayles P C , Wassom D L 
Published: January 2023

Abstract
Inbred and H-2 congenic mouse strains were tested for their ability to resist infections with the non-lethal 17X or with the lethal YM isolates of Plasmodium yoelii. DBA/2 and B10.D2 mice, which best resisted infections with non-lethal P. yoelii, were exquisitely susceptible to infection with lethal isolates of this malaria species. In contrast, B6 and B10 mice, which were susceptible to infection with non-lethal P. yoelii, were resistant to infection with the lethal isolates. This reversal of host response phenotype was influenced by H-2 genes, as evidenced by the divergent responses of the H-2 congenic strains B10 and B10.D2. However, a survey of mouse strains sharing common H-2 genes, but expressing different genetic backgrounds, demonstrated that genes outside the H-2 complex also influence the outcome of P. yoelii infections. By enumerating the numbers of P. yoelii-specific antibody-secreting cells in the spleens of infected mice, it was demonstrated that B6 mice, although susceptible to infection with non-lethal P. yoelii, nonetheless made a far stronger anti-parasite response after infection than did resistant DBA/2 mice. Using FACS analysis it was shown that infected B6 mice also produced large amounts of antibodies which bound to the surface of uninfected RBC. Thus, in B6 mice infected with non-lethal P. yoelii, a strong parasite-induced immune response was associated with susceptibility rather than resistance to infection. When T cell-deficient nude mice and their normal littermates were infected with the different isolates of P. yoelii, the nude mice had lower levels of parasitemia and higher RBC counts during the early stages of these infections, and lived longer than did normal littermates after infection with the lethal isolate. These data and the data from studies of B6 and DBA/2 mice support the idea that a strong immune response may be associated with susceptibility rather than resistance to P. yoelii, at least during the early stages of the infection. The finding that a single strain of mouse may present as resistant to infection with one P. yoelii isolate yet be exquisitely susceptible to infection with another suggests that the outcome of these murine malaria infections is dependent on a dynamic interplay between host and parasite genes. Thus, when genetic variability exists in both the host and the parasite populations, as would occur in nature, there may be little directed evolutionary change toward one phenotype or another.(ABSTRACT TRUNCATED AT 400 WORDS)