bluuebunny/crossref_metadata_2025_split huggingface dataset:
TNF-alpha response of human monocyte-derived macrophages to Mycobacterium avium, serovar 4, is of brief duration and protein kinase C dependent.
Authors: Gan H , Newman G , McCarthy P L , Remold H G 
Published: December 2022

Abstract
Human monocyte-derived macrophages (M phi) from the majority of normal donors respond to inoculation with Mycobacterium avium, serotype 4, (MAI) by elaboration of the inflammatory monokines TNF-alpha, IL-1 beta, and IL-6, which are of central importance for the protection against bacterial and parasitic infections. Peak TNF-alpha mRNA levels were of brief duration, being maximal at 1.5 h, and were only slightly higher than background levels at 4 h. Increases of IL-1 beta and IL-6 mRNA levels, on the other hand, persisted for 48 to 72 h. In contrast to LPS, MAI induced the production of only small amounts of TNF-alpha protein in the first 12 h and of large amounts of IL-1 beta and IL-6 protein between 3 and 72 h. MAI-induced TNF-alpha transcripts, in contrast to LPS induced TNF-alpha transcripts, were highly unstable. Their accumulation was blocked and their t 1/2 significantly decreased by the protein kinase C inhibitor staurosporine. In contrast, LPS-induced increases of TNF-alpha mRNA levels and MAI-induced increases of IL-1 beta and IL-6 mRNA levels were PKC independent. The cAMP- and cGMP-dependent protein kinase inhibitors, KT5720 and KT5823, respectively, and the tyrosine kinase inhibitors herbimycin and erbstatin had no effect on the MAI-dependent mRNA accumulation of TNF-alpha, IL-1 beta, and IL-6. W7, a calmodulin-dependent protein kinase inhibitor, was inhibitory in all cases. Thus, MAI-induced TNF-alpha mRNA accumulation is of short duration and PKC dependent. MAI-induced TNF-alpha protein production is low, possibly resulting in a mitigated antimicrobial effect.
Macrophage phagocytosis of virulent but not attenuated strains of Mycobacterium tuberculosis is mediated by mannose receptors in addition to complement receptors.
Authors: Schlesinger L S 
Published: December 2022

Abstract
We have examined macrophage receptors that mediate phagocytosis of virulent strains (Erdman and H37Rv) and an attenuated strain (H37Ra) of the intracellular pathogen, Mycobacterium tuberculosis. Adherence of the three strains to monocyte-derived macrophages (MDM) is markedly enhanced (&gt;threefold) in the presence of low levels of fresh serum and requires heat-labile serum components because heat inactivation of serum reduces adherence by 65 +/- 5 to 71 +/- 2%. In the presence and absence of serum, adherence of the three strains to MDM is comparable. By electron microscopy, all bacteria are ingested and reside in phagosomes. C receptors (CR) play an important role in adherence of the three strains to MDM in the presence and absence of serum. mAb against CR1, CR3, and CR4 inhibit adherence of Erdman M. tuberculosis in fresh serum by 75 +/- 3% and inhibit the low level of adherence of Erdman (71 +/- 13%), H37Rv (72 +/- 1%), and H37Ra (64 +/- 14%) M. tuberculosis in the absence of serum. Mannose receptors (MR) play an important role in mediating macrophage adherence of the virulent strains but not the attenuated strain of M. tuberculosis. Preincubation of MDM with soluble mannan or mannose-BSA consistently and significantly inhibits adherence of Erdman and H37Rv (up to 60 +/- 7%) but not H37Ra (0 +/- 1 to 5 +/- 5% enhancement of adherence) in the absence of serum. Down-modulation of macrophage MR on mannan substrates inhibits adherence of Erdman (52 +/- 8%) and H37Rv (55 +/- 6%) but not H37Ra (2 +/- 2% enhancement of adherence). Preincubation of MDM with soluble N-acetylglucosamine-BSA also significantly inhibits adherence of the virulent strains (42 +/- 3%). Preincubation of MDM with glucose-BSA minimally inhibits adherence of the three strains (2 +/- 4 to 12 +/- 5%). Anti-MR antibody inhibits adherence of Erdman (57 +/- 2%) and H37Rv (44 +/- 4%) but not H37Ra (4 +/- 5% enhancement of adherence). Inhibition of adherence of zymosan was comparable with that seen with virulent strains of M. tuberculosis in these studies. Down-modulation of macrophage MR also inhibits adherence of Erdman (48 +/- 9%) and H37Rv (20 +/- 2%) in the presence of serum. Simultaneous blockade of MR and CR does not further inhibit adherence of the virulent M. tuberculosis strains over that seen with blocking CR alone.(ABSTRACT TRUNCATED AT 400 WORDS)
Recognition of human melanoma cells by HLA-A2.1-restricted cytotoxic T lymphocytes is mediated by at least six shared peptide epitopes.
Authors: Slingluff C L , Cox A L , Henderson R A , Hunt D F , Engelhard V H 
Published: December 2022

Abstract
HLA-A2.1-associated peptides were extracted from human melanoma cell lines and used to study epitopes for melanoma-specific HLA-A2.1-restricted CTL. CTL were generated from tumor-involved nodes by in vitro stimulation, initially with autologous melanoma cells and subsequently with allogeneic A2.1+ melanoma cells. These CTL lysed autologous melanoma plus four allogeneic HLA-A2.1+ melanomas, including an HLA-A2.1-transfected melanoma. K562, HLA-A2- melanomas and HLA-A2+ nonmelanomas were not lysed. HLA-A2.1 molecules were purified from human melanoma cell lines by immunoaffinity column chromatography of detergent-solubilized cell pellets. Peptides bound to the MHC molecules were acid eluted and fractionated by reversed phase HPLC. Individual fractions were assessed for their ability to reconstitute melanoma-specific epitopes by addition to the HLA-A2.1+ Ag-processing mutant, 721.174XCEM.T2 (T2). Five peaks of reconstitution were observed. Second dimension HPLC separations of reconstituting fractions revealed evidence for two distinct reconstituting peptides within one of these peaks. Based on these data, a minimum of six distinct peptides associated with HLA-A2.1 and recognized by melanoma-specific CTL are present on these different melanoma lines. These data document the presence of multiple peptide-defined CTL epitopes that are shared by at least three unrelated human melanoma cell lines.
Identification of a chemotactic domain of the pro-inflammatory S100 protein CP-10.
Authors: Lackmann M , Rajasekariah P , Iismaa S E , Jones G , Cornish C J , Hu S , Simpson R J , Moritz R L , Geczy C L 
Published: December 2022

Abstract
We previously reported the purification and partial amino acid sequence of a novel murine cytokine designated CP-10, which has chemotactic activity for murine polymorphonuclear cells (PMN) and macrophages. The complete cDNA encoding an 88-amino acid polypeptide has been isolated and the sequence is presented here. Transient transfection of CP-10 cDNA into CV-1 cells confirmed the chemotactic activity of rCP-10 for murine PMN. CP-10 has sequence homology with members of the S100 family of Ca(2+)-binding proteins with pronounced amino acid sequence similarities within the putative N- and C-terminal Ca(2+)-binding sites, but differences within their connecting hinge and C-terminal regions. We have confirmed the hypothesis of Kligman and Hilt that functional specificity of individual members of the S100 protein family may reside in the hinge region. A synthetic peptide corresponding to the hinge region of CP-10 (CP-10(42-55) was compared with native CP-10 in chemotaxis and skin test assays. Native CP-10 had potent activity for phagocytic cells, but not lymphocytes, in vitro (optimal activity, 10(-11) to 10(-13) M) and elicited a sustained recruitment of neutrophils and mononuclear cells over 24 h in vivo. The hinge-region peptide had strong chemotactic activity for murine phagocytic cells (optimal activity, 10(-10) - 10(-11) M) but elicited only a transient infiltration of neutrophils over 4 to 8 h after intradermal injection. Results indicate that although the hinge region contributes significantly to the functional specificity of the S100 protein CP-10, sustained cellular recruitment typical of a delayed type hypersensitivity response is apparently dependent on the structural integrity of the protein.
Differential regulation of formation of multinucleated giant cells from concanavalin A-stimulated human blood monocytes by IFN-gamma and IL-4.
Authors: Takashima T , Ohnishi K , Tsuyuguchi I , Kishimoto S 
Published: December 2022

Abstract
We found that in vitro multinucleated giant cells (MGC) could be produced by incubation of highly purified human blood monocytes with Con A alone, and the effect of Con A was dose- and time-dependent. Any of the cytokines considered as macrophage-activating factor, such as IFN-gamma, IL-2, IL-4, GM-CSF, or TNF-alpha, did not induce MGC by itself. When added to monocyte cultures, however, IFN-gamma enhanced Con A-induced MGC formation in a dose-dependent manner. In contrast, IL-4 suppressed this response in a dose- and time-dependent manner. IL-4 antagonized the enhancing effect of IFN-gamma on Con A-induced MGC formation. This ability to suppress the formation of MGC was completely abrogated after treatment with anti-IL-4 antibody. In addition, the involvement of monokines (IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha) in Con A-induced monocyte fusion was investigated by adding various antimonokine polyclonal antibodies in cultures. Normal rabbit IgG, anti-IL-1 alpha rabbit antibody, and anti-IL-1 beta rabbit antibody had no effect on Con A-induced MGC formation. However, anti-TNF-alpha rabbit antibody had suppressed the monocyte fusion induced by Con A in a dose-dependent manner, and a high dose of anti-IL-6 rabbit antibody had a partially suppressive effect. Anti-TNF-alpha mAb also had an inhibitory effect on monocyte fusion. Furthermore, the enhancing effect of IFN-gamma on this response was entirely abrogated by anti-TNF-alpha rabbit antibody. There was a highly significant positive correlation between the fusion rates of monocytes and the levels of TNF-alpha produced by monocytes (r = 0.68, p &lt; 0.0005). Our results indicate that T cell-derived lymphokines, such as IFN-gamma and IL-4, have mutually antagonistic effects on Con A-induced human MGC formations in vitro, in which the expression of TNF-alpha in human monocytes plays a key role in the fusion process of monocytes.
Circulating HIV-specific CD8+ cytotoxic T cells express CD38 and HLA-DR antigens.
Authors: Ho H N , Hultin L E , Mitsuyasu R T , Matud J L , Hausner M A , Bockstoce D , Chou C C , O'Rourke S , Taylor J M , Giorgi J V 
Published: December 2022

Abstract
CD38, a molecule with multilineage distribution but unknown function, and the MHC class II molecule HLA-DR (DR) have markedly elevated levels of expression on CD8+ cells of HIV-infected people. This study investigated the expression of CD38 and DR Ag on circulating HIV-specific CD8+ CTL in HIV-seropositive subjects. Purified CD8+ lymphocytes from 22 participants in the University of California at Los Angeles Multicenter AIDS Cohort Study were screened for CTL activity against autologous EBV-immortalized lymphoblast targets infected with vaccinia vectors that carried HIVIIIB gag, pol, and env genes. Sixty-seven percent (14 of 21), 64% (14 of 22), and 9% (2 of 22), respectively, of the subjects had HIV-specific CD8+ CTL activity against gag, pol, and env proteins. CD8+ cells from 11 of the subjects who had high CTL activity were then FACS-separated using three-color immunofluorescence sorting. Circulating DR-CD38- CD8+ cells had little activity. Highly purified DR+CD38+ CD8+ cells had higher HIV-specific CTL activity than other CD8+ cells. DR+CD38- or DR-CD38+ CD8+ cells also mediated significant activity, but only about half as much on a per cell basis as DR+CD38+ CD8+ cells. This is the first report that the CD38 molecule is expressed in vivo on Ag-specific CD8+ CTL, and confirms previous reports that DR is expressed on these cells. Both asymptomatic HIV-seropositive subjects (144 +/- 132/mm3) and AIDS patients (253 +/- 178/mm3) had markedly elevated levels of DR+CD38+ CD8+ cells compared with the levels in HIV-seronegative controls (7 +/- 3/mm3). However, the level of anti-HIV CTL activity was not correlated with the level of DR+CD38+ CD8+ cells, indicating that enumeration of this lymphocyte population by flow cytometry most likely will not be a useful surrogate for measuring functional CTL activity. Low levels of HIV-specific CTL activity, especially against gag, were correlated with lower CD4+ cells numbers, suggesting that the loss of CD8+ T cell cytotoxic activity against HIV that has been reported to occur with advancing HIV disease progression may reflect in part the extent of CD4+ cell immunodeficiency in HIV-infected subjects.
Monoclonal antibody to rubella virus capsid protein recognizes a beta-cell antigen.
Authors: Karounos D G , Wolinsky J S , Thomas J W 
Published: December 2022

Abstract
The high frequency of insulin-dependent diabetes (IDDM) in children with congenital rubella suggests that the infectious agent may trigger the autoimmune process. To explore the immunologic relationship between rubella virus and IDDM, we examined a panel of mAb that recognizes rubella virus capsid and envelope glycoproteins for reactivity with islet cell Ag. One mAb, C9, which recognizes a defined domain within the capsid protein of rubella virus, was found to react with extracts from a rat beta-cell tumor and normal rat and human islets. Using one and two dimensional immunoblot analysis of rat beta-cell tumor extracts, the C9-like epitope was found to reside on a 52 kDa protein that is also the target of autoantibodies from human IDDM and nonobese diabetic mice. To confirm this cross-reactivity, antibodies in diabetic sera were absorbed to the recombinant rubella virus capsid protein, eluted, and then shown to react with the 52 kDa insulinoma protein. These data show that an immunogenic epitope on the rubella virus capsid protein is mimicked by a similar structure on a beta-cell protein. These findings suggest that rubella virus has the potential to sensitize susceptible individuals for an autoimmune response to beta-cell Ag and identify one mechanism that may contribute to beta destruction in IDDM.
Characterization of the mouse autoantigen La (SS-B). Identification of conserved RNA-binding motifs, a putative ATP binding site and reactivity of recombinant protein with poly(U) and human autoantibodies.
Authors: Topfer F , Gordon T , McCluskey J 
Published: December 2022

Abstract
To facilitate the study of autoimmunity to the nuclear Ag La (SS-B) we have isolated and characterized cDNA encoding the mouse La (SS-B) protein. Mouse La (SS-B) protein has 76.7% identity to both human and bovine La (SS-B) proteins and the previously recognized RNP-binding motifs were noted to be highly conserved across the three species. Examination of the primary sequence of human and bovine La (SS-B) newly identifies the site of a potential ATP-binding motif G/AXXXXGK which is preserved in mouse La (SS-B) despite a unique 16 amino acid insertion present in this region of the mouse protein. Analysis of mouse genomic DNA suggests a single gene encodes mouse La (SS-B) and no restriction fragment polymorphisms were identified in the three mouse strains investigated. Two alternate 5' untranslated regions were identified in mouse La (SS-B) cDNA and La (SS-B) mRNA was identified in a wide range of murine tissues consistent with its ubiquitous expression. Recombinant mouse La (SS-B) protein purified from Escherichia coli was shown to bind to poly(U) agarose and to react with sera containing anti-La (SS-B) antibodies obtained from patients with Sjögren's syndrome. The ability to produce recombinant mouse La (SS-B) should provide a valuable reagent for the study of the cellular autoimmune response as well as immunologic tolerance to La (SS-B) Ag in mice.
Immunization with recombinant BCG-SIV elicits SIV-specific cytotoxic T lymphocytes in rhesus monkeys.
Authors: Yasutomi Y , Koenig S , Haun S S , Stover C K , Jackson R K , Conard P , Conley A J , Emini E A , Fuerst T R , Letvin N L 
Published: December 2022

Abstract
Because the transmission of HIV is likely to occur through cell-associated virus, an effective HIV vaccine should be capable of eliciting HIV-specific CTL. We have employed the simian immunodeficiency virus (SIV)/rhesus monkey model to explore the use of the attenuated tuberculosis bacillus, Calmette Guérin bacillus (BCG), as a vaccine vehicle to elicit AIDS virus-specific CTL. BCG was engineered to express SIVmac gag under the control of hsp70 regulatory sequences. Immunization with this rBCG-SIVmac gag elicited MHC class I-restricted, CD8+ SIVmac gag-specific CTL in rhesus monkeys. In fact, SIVmac gag-specific CTL could be cloned readily from peripheral blood lymphocytes of these immunized monkeys. These findings provide further evidence for the power of BCG as a vaccine vector and its continued exploration as a vehicle for eliciting HIV-specific immunity.
Memory effectors: a potent, IL-4-secreting helper T cell population that develops in vivo after restimulation with antigen.
Authors: Bradley L M , Duncan D D , Yoshimoto K , Swain S L 
Published: December 2022

Abstract
Resting CD4+ memory T cells from the spleens of mice primed more than 6 wk earlier with KLH in adjuvant produce IL-2 and IL-3, but only low levels of IL-4 and IFN-gamma, and undetectable IL-5 after specific restimulation in vitro. In contrast, when previously primed mice are boosted by i.v. injection of soluble KLH, a CD4+ T cell population develops in the spleen that can produce greatly increased levels of IL-4, and variably increased IL-2, IFN-gamma, and/or IL-3. The ability of these memory effector Th cells to be restimulated to secrete cytokines is maximal by 3 days after in vivo boosting with Ag, and declines rapidly thereafter. Memory effector Th are induced in the spleens of KLH-primed mice that have been depleted of precursor T cells by thymectomy more than 25 wk previously, suggesting that they are derived from a memory T cell population. Cell separation on the basis of CD45RB or MEL-14, surface markers that are down-regulated on memory CD4+ cells, indicates that memory effector Th are in the CD45RBlo and MEL-14- subsets of CD4+ T cells. The frequency of KLH-specific splenic CD4+ T cells with the capacity to secrete cytokines in limiting dilution cultures is very low in unprimed mice (1/3 x 10(4) to 1/9 x 10(4)), but increases as much as 50-fold after priming. IL-2, but not IL-4, can be detected in the supernatants of stimulated unprimed CD4+ T cells. Both IL-2- and IL-4-producing cells are readily detected after priming, and frequencies of IL-2-secreting cells (1/250 to 1/4000) are up to ninefold greater than those for IL-4 secreting cells. Boosting elicits variable (two to eightfold) increases in the frequencies of both IL-2- and IL-4-producing CD4+ T cells. However, high IL-4 titers associated with memory effector Th function can be obtained when significant frequency changes are not detected after boosting. The data suggest that reactivation of resting memory Th in vivo induces their differentiation into effector Th with the capacity to secrete much higher levels of IL-4. Although the capacity to produce high levels of IL-4 is associated with both primary and memory CD4+ effector populations, memory effector Th are the higher producers.(ABSTRACT TRUNCATED AT 400 WORDS)
Differential recruitment of viral and allo-epitopes into the MHC class I antigen processing pathway of a novel mutant of Ltk- cells. HSV/MHC class I restriction/immune recognition/antigen processing/antigen presentation/influenza virus.
Authors: Lippé R , Kolaitis G , Michaelis C , Tufaro F , Jefferies W A 
Published: December 2022

Abstract
It is generally thought that the Ag processing pathways for endogenously synthesized proteins are the same for allo and viral Ag processing. However, this view does not take into consideration the diversity of specialized maturation and assembly pathways for viruses. In particular, viral assembly that takes place within intracellular membranes may require unique Ag processing steps. In this study we sought to assess this possibility. Hence, we describe the CTL response against a murine Ltk- cell derivative, gro29, which was previously shown to be defective in the propagation of herpes simplex virus type 1 (HSV-1). In HSV-1-infected gro29 cells, viral polypeptides are synthesized in normal amounts and viral assembly takes place. However, transport of the assembled particles is defective in these cells, resulting in the accumulation of noninfectious virus in cytoplasmic vesicles, and a reduction in the release of viral particles by at least 2000-fold. We show that the rate of transport of individual endogenous proteins through the organelles of the secretory pathway is also impaired, but only by roughly 50%, suggesting that the defect in this cell line affects the transport of particles to a greater extent than the transport of individual proteins. It is also shown that allogeneic and influenza A- specific CTL responses are indistinguishable between gro29 and Ltk- cells, as is the response against target cells pretreated with a influenza A derived synthetic peptide. By contrast, HSV-1-infected gro29 cells are approximately eightfold less sensitive than infected Ltk- cells to lysis by HSV-1-specific CTL. This illustrates that in contrast to the allogeneic and influenza specific responses, the recruitment of herpes virus-specific Ag into the Ag-processing pathway is dependent on a cellular function that is also required for viral maturation and egress. We believe that this is the first demonstration of this phenomenon.
IL-10 inhibits T cell-independent but not T cell-dependent responses in vitro.
Authors: Peçanha L M , Snapper C M , Lees A , Yamaguchi H , Mond J J 
Published: December 2022

Abstract
Lymphokines play a key role in T cell-independent (TI) Ag-induced responses. We recently showed that IL-10 potently inhibits Ig production stimulated by TI-2 Ag + IL-5. In view of our recent findings that the B cell activator can determine the effect lymphokines will have on Ig production and on isotype selection, we analyzed the effect of IL-10 on Ig production induced by other TI antigens and T cell-dependent Ag. These data demonstrate that IL-10 inhibited IL-5-induced Ig production stimulated by TI-1 and by TI-2 Ag, but had no effect on an in vitro T cell-dependent Ag-specific anti-SRBC-induced response or on a T cell-induced polyclonal response mediated by anti-CD3-activated T cell clones. IL-10 inhibited IgM, IgG1, IgG2a, and IgG3 secretion by B cells costimulated by LPS or anti-delta-dextran. IL-10 did not interfere with induction of class II MHC Ag expression or cell enlargement that was stimulated by LPS or anti-delta-dextran and had no detrimental effect on cell viability. IL-4 reversed the IL-10-mediated inhibition of IgG1 and IgM secretion stimulated by anti-delta-dextran or LPS-activated cells in the presence of IL-5. A 72 h, but not 24 h, exposure to IL-4 at initiation of culture with anti-delta-dextran + IL-5 + IL-10 was necessary to reverse the IL-10-mediated inhibition of IgM secretion. Our data suggest that IL-10 can selectively inhibit TI Ag-induced responses when other T cell-derived stimulatory lymphokines are not present and further emphasize the specific role of the B cell activator in influencing the responsiveness of B cells to lymphokines.