bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibacterial properties of eosinophil major basic protein and eosinophil cationic protein.
Authors: Lehrer R I , Szklarek D , Barton A , Ganz T , Hamann K J , Gleich G J
Published: December 2022

We examined the bactericidal activity of two proteins that are abundant in the cytoplasmic granules of human eosinophils, major basic protein (MBP) and eosinophil cationic protein (ECP). Unlike the human neutrophil's peptide defensins, both MBP and ECP killed stationary phase Staphylococcus aureus 502A in a simple nutrient-free buffer solution. Although MBP also killed Escherichia coli ML-35 with considerable efficacy under these experimental conditions, the in vitro activity of ECP against E. coli was considerably enhanced if mid-logarithmic phase bacteria replaced stationary phase organisms or if the assay medium was enriched with trypticase soy broth. The antibacterial activity of both eosinophil proteins was modulated by incubation time, protein concentration, temperature and pH. A pBR322-transformed derivative of E. coli ML-35 was used to examine the effects of ECP and MBP on integrity of the bacterial inner membrane (IM) and outer membrane. Although both MBP and ECP caused outer and inner membrane permeabilization when nutrients were present, only MBP was effective under nutrient-free conditions. Two proton ionophores (DNP and carbonyl cyanide m-chlorophenyl hydrazone) protected E. coli from the bactericidal effects of ECP but not from MBP. These findings establish that MBP and ECP have bactericidal properties and suggest that these proteins kill E. coli by similar but nonidentical mechanisms marked by an attack on the target cell's membranes. In view of evidence that high concentrations of ECP and MBP exist in cytoplasmic granules whose contents are translocated to phagocytic vacuoles, we suggest that MBP and ECP contribute to the eosinophil's ability to kill ingested bacteria.
Mouse hepatitis virus 3 replication in T and B lymphocytes correlate with viral pathogenicity.
Authors: Lamontagne L , Descoteaux J P , Jolicoeur P
Published: December 2022

Viral pathogenicity may be regulated by host defense mechanisms at the virus-immune cell interaction level. The immune system plays an important role in the outcome of acute disease induced by the mouse hepatitis virus type 3 (MHV3) virus. The lymphoid cells act as effectors in the virus elimination as well as targets for viral replication. In order to demonstrate a correlation between MHV3 pathogenicity and viral replication in lymphocytes, genetically-determined resistant A/J and susceptible C57BL/6 mice were infected with pathogenic (L2-MHV3) or nonpathogenic (YAC-MHV3) viral strains. Pathogenicity and histopathologic studies have revealed that lymphoid organs such as thymus and spleen, showed injuries or atrophy in susceptible mice infected with L2-MHV3. No histopathologic lesions in the lymphoid organs occurred in C57BL/6 mice infected with YAC-MHV3 or A/J mice infected with both viruses. The mechanisms involved in the lymphoid injuries were studied regarding viral replication in the lymphoid organs and cells in infected mice. Results indicate that cell depletion in lymphoid organs is caused by a complete viral replication in lymphoid cells. Thy1.2+ and surface IgM+ lymphoid cells from susceptible C57BL/6 mice infected with L2-MHV3 were permissive to viral replication and to subsequent cell lysis. No cell lysis, however, occurred in lymphoid cells from C57BL/6 mice infected with YAC-MHV3 and A/J mice infected with both virus strains. In vitro studies, with purified T and B cell populations were performed to determine the mechanism effecting susceptibility or resistance to viral-induced cell lysis occurring in such cells. A blockade, probably occurring at the viral RNA polymerase activity level, prevents viral replication in resistant cells between the stages of fixation of the virus at the cell-surface receptor and the viral protein translation. These experiments indicate that an intrinsic virus-specific resistant mechanism occurs in lymphoid cells that plays a major role in the viral pathogenicity.
Diversity of Ig V gene segments found in anti-DNA autoantibodies from a single (NZB x NZW)F1 mouse.
Authors: Panosian-Sahakian N , Klotz J L , Ebling F , Kronenberg M , Hahn B
Published: December 2022

We have studied 18 anti-DNA secreting hybridomas derived from a single, nephritic NZB/NZW mouse. The antibodies were analyzed for the expression of idiotypic families that are enriched in the antibodies to DNA from diseased animals (IdGN2 and IdX), and for the expression of VH and V kappa gene segment subfamilies. Most of the mAb have characteristics similar to those that may be pathogenic because they 1) bound to native DNA, 2) were of the IgG2a or IgG2b isotype, and 3) expressed idiotopes associated with glomerulonephritis in NZB/NZW mice and human lupus. Among the 18 mAb, at least six VH subfamilies and six V kappa subfamilies were expressed. A majority of the antibodies utilized a VH gene segment from the large J558 subfamily. Slot blot analyses of total spleen cell RNA revealed that as NZB/NZW mice aged and developed nephritis, they expressed progressively higher quantities of Ig transcripts. The proportion of these transcripts derived from the VH J558 subfamily also increased. Our results indicate that a diversity of B cell clones participate in the anti-DNA response of a single NZB/NZW mouse. There was no preferential utilization of 3' Ig V gene segment subfamilies. Furthermore, there was no marked difference in the pattern of VH and V kappa gene segment expression in antibodies defined by their isotypes or idiotopes.
Linkage analysis of the Bcg gene on mouse chromosome 1. Identification of a tightly linked marker.
Authors: Schurr E , Skamene E , Forget A , Gros P
Published: December 2022

We have mapped and determined the gene order of five cloned genes in the vicinity of the murine host resistance gene Bcg on mouse chromosome 1. For this, we have used a RFLP-type analysis in panels of 43 recombinant inbred strains, 3 congenic mouse strains, and 186 segregating backcross progeny derived from inbred strains of Bcgr and Bcgs genotypes. The Bcg alleles of segregating animals were established by in vivo infection with Mycobacterium bovis (Bacillus Calmette-Guérin) strain Montreal. Genomic DNA prepared from progenitor mouse strains was isolated, digested with restriction endonucleases, and analyzed by Southern blotting to identify strain-specific RFLP for each DNA marker tested. Among a number of DNA markers tested, Len2, Fn, Vil, Alpi, and Achrg were found to co-segregate with Bcg in mouse strains congenic for this locus. Detailed segregation analysis of the five markers and Bcg showed that Vil was extremely close to Bcg with no recombinant identified, whereas Fn and Len2 were located 4.5 and 9 cM proximal of Bcg, respectively. Alpi and Achrg mapped 5 and 5.5 cM distal from Bcg, respectively. Pedigree analysis in the recombinant inbred strains and backcross animals indicated the gene order: centromere-Len2-Fn-Vil,Bcg-Alpi-Achrg. The tightly linked Vil marker can now be used as an entry point in recombinant genomic DNA libraries to clone sequences overlapping Bcg. This group of five genes flanking Bcg on mouse chromosome 1 is precisely conserved on the telomeric end of the long arm of human chromosome 2q. Our results suggest that a likely location for a putative human homologue to the murine host resistance gene Bcg is the long arm of human chromosome 2 (2q32-qter).
Human tumor infiltrating lymphocytes. Analysis of lymphokine mRNA expression and relevance to cancer immunotherapy.
Authors: Belldegrun A , Kasid A , Uppenkamp M , Topalian S L , Rosenberg S A
Published: December 2022

Tumor infiltrating lymphocytes (TIL) isolated from 12 patients with metastatic malignant melanoma, renal cell carcinoma, or breast adenocarcinoma were expanded in rIL-2 for 22 to 45 days (median 33 days) and analyzed for lymphokine mRNA expression and patterns of TCR gene rearrangement. All TIL cultures were significantly enriched for T cells, with CD3+ CD8+ cells predominant in 8 of 10 cases tested, and demonstrated an oligoclonal (rather than polyclonal) pattern of TCR gene rearrangement. Nine of 12 cultures could effectively lyse the autologous targets in short term chromium release assays. IL-2 expanded-TIL expressed mRNA for TNF-alpha and TNF-beta (lymphotoxin) and, in 5 of 9 (41%) cases, granulocyte/macrophage-colony stimulating factor mRNA but not IL-1 beta or IL-2 transcripts. Cultured TIL deprived of rIL-2 for 4 days did not constitutively express mRNA for any of the lymphokines tested. One long term TIL line in culture was followed and periodically tested for lytic activity and TNF-mRNA expression. Loss of the specific cytolytic but not proliferative activity at day 85 was associated with disappearance of TNF mRNA. Profiles of lymphokine secretion may provide a useful marker for functionally characterizing different T cell subsets and may provide correlates of the in vivo anti-tumor effects of these cells when TIL are adoptively transferred into cancer-bearing patients.
Role of tumor necrosis factor-alpha in E1A oncogene-induced susceptibility of neoplastic cells to lysis by natural killer cells and activated macrophages.
Authors: Cook J L , May D L , Wilson B A , Holskin B , Chen M J , Shalloway D , Walker T A
Published: December 2022

NIH-3T3 cells transfected with adenovirus E1A oncogene cDNA were found to exhibit cytolytic susceptibility to murine NK cells and activated macrophages associated with a threshold level of oncogene product expression exceeding that required for morphological transformation. A similar correlation was observed between threshold levels of E1A gene product expression and target cell susceptibility to direct cytotoxicity by rTNF. Inhibition of splenic NK cell and peritoneal macrophage cytolysis by antisera specific for murine rTNF confirmed the importance of E1A-induced TNF susceptibility as one determinant of target cell cytolytic susceptibility. Anti-TNF antibody was, however, unable to block killing of E1A-expressing targets by the NK cell line, NKB61A2. These results suggest a direct link between the functions of E1A oncogene products and cellular mechanisms of action of TNF elaborated by host effector cells and indicate that E1A expression also affects target cell susceptibility to TNF-independent cytolytic mechanisms.
Unusually high frequencies of HIV-specific cytotoxic T lymphocytes in humans.
Authors: Hoffenbach A , Langlade-Demoyen P , Dadaglio G , Vilmer E , Michel F , Mayaud C , Autran B , Plata F
Published: December 2022

CTL specific for the HIV belong to the CD8 subset of T lymphocytes, and their activity is restricted by class I HLA transplantation Ag. In this report, HIV-specific CTL and their precursor cells were quantified by limiting dilution analysis. CTL were recovered from the lungs, lymph nodes, and blood of asymptomatic seropositive carriers and of patients with AIDS. HIV was found to be very immunogenic. High frequencies of both HIV-specific CTL and CTL precursor cells were detected in infected individuals. These CTL killed autologous HIV-infected macrophages and T4 lymphoblasts. They also killed doubly transfected P815-A2-env-LAV mouse tumor cells, which express the human HLA-A2 gene and the HIV-1 env gene. In the longitudinal studies of two HIV-infected patients, CTL and CTL precursor cell frequencies decreased as the clinical and immunologic status of the patients deteriorated. Most surprisingly, PBL from seronegative donors also responded to HIV stimulation in vitro and generated large numbers of HLA-restricted, HIV-specific CTL.
Transfusion induces blood donor-specific suppressor cells.
Authors: Quigley R L , Wood K J , Morris P J
Published: December 2022

Transfusion with blood from the organ donor before transplantation can prolong the survival of renal allografts in the rat. To determine if the beneficial effect of preoperative blood transfusion was due to the generation of donor-specific suppressor cells, in vivo and in vitro adoptive transfer experiments were performed. Lymphoid cells were harvested from transfused and untreated rats. These cells were then either (1) transferred to lightly irradiated (200 R) syngeneic hosts which were subsequently challenged with a kidney allograft (in vivo assay) or (2) titrated as regulator cells into naive unidirectional MLC such that the regulator and responder populations were syngeneic. In the LEW-RT1 to DA-RT1av1 strain combination, the adoptive transfer of thoracic duct lymph (TDL) or lymph node (LN) cells (5 x 10(7) to 7.5 x 10(7) cells) from DA animals transfused with LEW blood, 7 days previously into syngeneic (DA), lightly irradiated (200 R) hosts resulted in the indefinite survival of LEW kidney allografts. The phenomenon was blood donor-specific and dose-dependent. In contrast the adoptive transfer of spleen cells (10(7) to 10(8] from blood transfused hosts 7 days after transfusion had no effect on renal allograft survival. In vitro the addition of LN or TDL regulator cells, harvested from DA rats transfused with LEW blood, to a unidirectional MLC (DA responders, LEW stimulators) resulted in a significant depression of the proliferative response when compared with the proliferation of these same cells without the addition of these regulator cells or with the addition of LN or TDL regulator cells from a DA rat transfused with third party (PVG-RT1c) blood. The depression of the proliferative response observed in vitro, was blood donor specific. When LN or TDL regulator cells from a DA rat transfused with PVG-RT1c blood were added to a unidirectional MLC between DA responders and PVG stimulators, a significant depression in the proliferative response was observed. These in vitro findings were confirmed in two other strain combinations (LEW-PVG, and DA-PVG). Thus a single blood transfusion results in the induction of donor-specific suppressor cells detectable both in vivo and in vitro 7 days after transfusion in some but not all lymphoid compartments.
Organ-specific autoimmune disease induced in mice by elimination of T cell subsets. V. Neonatal administration of cyclosporin A causes autoimmune disease.
Authors: Sakaguchi S , Sakaguchi N
Published: December 2022

Cyclosporin A (CsA), a potent immunosuppressive drug, caused organ-specific autoimmune disease, such as gastritis with anti-parietal cell autoantibodies or oophoritis with anti-oocyte autoantibodies, in BALB/c mice when the drug was administered daily for 1 wk to newborns. Administration to adult mice did not. CsA abrogated the production of L3T4+ T cells and Lyt-2+ T cells in the thymus. Consequently, these T cells were substantially depleted from the peripheral lymphoid organs, especially when the drug was administered from the day of birth. Autoimmune disease was prevented when CsA-treated newborn mice were inoculated with splenic T cells from normal syngeneic mice. However, removal of the thymus immediately after neonatal CsA treatment produced autoimmune disease with a higher incidence and in a wider spectrum of organs, i.e., thyroiditis, sialoadenitis of the salivary gland, gastritis, insulitis of the endocrine pancreas, adrenalitis, oophoritis, or orchitis. Each autoimmune disease was accompanied by the development of circulating autoantibodies specific for the corresponding organ Ag. Immunopathology of these autoimmune diseases was quite similar to that of human organ-specific autoimmune diseases.
Binding the low affinity Fc epsilon R on B cells suppresses ongoing human IgE synthesis.
Authors: Sherr E , Macy E , Kimata H , Gilly M , Saxon A
Published: December 2022

Our results support the hypothesis that binding the low affinity Fc epsilon R (Fc epsilon R-II, CD23) on IgE-secreting B cells, directly suppresses IgE production. IgE production from AF-10/U266 (a human IgE plasmacytoma) decreased upon incubation with anti-IgE mAb or IgE:anti-IgE immune complexes (IgE-IC). Synthesis was suppressed a maximum of 51% with 10 micrograms/ml of IgE-IC after a 24-h incubation. Spontaneous in vitro IgE synthesis from the B cells of highly atopic individuals was also inhibited in a similar fashion. This effect was isotype specific as IgA or IgG immune complexes did not alter IgE production from AF-10 nor did IgE-IC affect IgA or IgG synthesis from lymphoblastoid cell lines making IgG (GM1500 and RPMI 8866) or IgA (GM1056). U266/AF-10 cells displayed both membrane IgE (greater than 90%) and Fc epsilon R-II (23%). To evaluate the role of these membrane proteins in the observed suppression of IgE synthesis, we treated U266/AF-10 cells with IgE-IC that bound Fc epsilon R-II but could not bind membrane IgE, as the mAb used was directed against an idiotypic determinant on the myeloma IgE (PS) used to make the IgE-IC. Suppression was maximal (greater than 50%) with these complexes at 0.1 micrograms/ml and at a 1/1 ratio of mAb anti-IgE to human myeloma IgE. When IgE-IC were used that were constructed with heat denatured IgE or F(ab')2 fragments of IgE, suppression was abrogated indicating IgE-Fc epsilon R binding was required. Neither PS IgE nor mAb 5.1 (the components of IgE-IC) alone affected IgE synthesis. Furthermore, a mAb binding directly to CD23 suppressed IgE synthesis from AF-10 up to 60%. Using limiting dilution analysis, we determined that IgE production per AF-10 cell was constant (0.9 pg/cell/24 h), independent of cell density and cells incubated with IgE-IC were uniformly suppressed. To clarify the mechanism of IgE-IC-induced suppression on AF-10 cells, we assessed both the proliferative rate and cell cycle distribution upon incubation with IgE-IC. There was no correlation between IgE production and [3H]TdR incorporation by AF-10 cells incubated with IgE-IC or anti-CD23 mAb. The distribution of cells within the cell cycle was unaffected by these treatments, with 60% of the cells in G1. These results define a direct role for the Fc epsilon R-II on B cells in the regulation of ongoing IgE synthesis.
Treatment with recombinant IFN-gamma decreases cell surface CD4 levels on peripheral blood monocytes and on myelomonocyte cell lines.
Authors: Faltynek C R , Finch L R , Miller P , Overton W R
Published: December 2022

The human cell surface protein CD4 is not only an important accessory molecule in the activation of MHC class-II-restricted T cells, but has also been implicated to be a receptor for the human immunodeficiency virus HIV-I on lymphoid and monocytic cells. We have found that a 24-h treatment of the promonocytic leukemia cell line U937 with rIFN-gamma decreases the expression of the CD4 Ag by 50% as measured by cytofluorographic analysis. The decrease in CD4 expression was dependent on the concentration of rIFN-gamma, with maximal effects occurring at 20 to 200 U/ml. The decrease appeared to be due to actual loss of the CD4 molecule from the cell surface rather than masking of a particular epitope, inasmuch as similar results were obtained with the OKT4 and OKT4A antibodies. The effect of rIFN-gamma to decrease CD4 expression was not due to a general loss of cell surface Ag, because the binding of OKM1 and anti-HLe-1 increased after rIFN-gamma treatment. Treatment of rIFN-gamma also decreased cell surface CD4 expression on the promyelocytic leukemia cell line HL-60, and on the monocytic cell line THP-1, although the extent of the decrease was less than on U937 cells. Freshly isolated normal peripheral blood monocytes treated for 48 h with rIFN-gamma bound much less OKT4 or OKT4A antibody than cells incubated in the absence of rIFN-gamma. Moreover, treatment with rIFN-gamma reduced the percentage of peripheral blood monocytes that were positive for the CD4 Ag. In contrast with the decrease in CD4 levels on rIFN-gamma-treated monocytes, treatment with rIFN-gamma had no effect on CD4 levels on peripheral blood T lymphocytes or T cell lines.
Both granulocyte-macrophage CSF and macrophage CSF control the proliferation and survival of the same subset of alveolar macrophages.
Authors: Lin H S , Lokeshwar B L , Hsu S
Published: December 2022

The effect of granulocyte-macrophage (GM)-CSF on the proliferation of murine pulmonary alveolar macrophages in vitro was investigated. About 20% of freshly isolated alveolar macrophages formed colonies in both liquid and soft agar cultures in the presence of GM-CSF. GM-CSF was also found to be capable of maintaining the survival of these colony-forming cells in vitro. Moreover, GM-CSF could substitute for CSF-1 in maintaining the survival of CSF-1-responding pulmonary alveolar macrophage colony-forming cells in the absence of CSF-1. The concentration of GM-CSF required for maintaining the survival of colony-forming cells without proliferation was much lower than that required for the proliferation of these cells in vitro. It also enhanced the CSF-1-dependent clonal growth of alveolar macrophages. These data suggest that the colony-forming cells that respond to GM-CSF are the same subset of macrophages that form colonies in the presence of CSF-1. GM-CSF did not inhibit the binding of 125I-CSF-1 to alveolar macrophages at 0 degrees C. However, the preincubation of macrophages with GM-CSF at 37 degrees C resulted in a transient down-regulation of CSF-1 binding activity.
Presence of IL-1 receptors on human and murine neutrophils. Relevance to IL-1-mediated effects in inflammation.
Authors: Parker K P , Benjamin W R , Kaffka K L , Kilian P L
Published: December 2022

Inflammatory responses are characterized by the infiltration of polymorphonuclear neutrophils (PMN) at the involved site. IL-1 may have an important role in mediating this response, but whether IL-1 acts directly on PMN is controversial. In this study, we examined PMN for the presence of IL-1R and determined the effect of IL-1 on PMN migration in vivo. Thioglycollate, proteose-peptone, or IL-1 elicited peritoneal exudate cells were found to bind 125I-IL-1 alpha in a specific and saturable manner. This binding was localized to the PMN in the exudate. Scatchard plot analysis indicates the presence of approximately 1700 receptors per PMN and an apparent dissociation constant of 3.0 x 10(-10) M. Binding sites for 125I-IL-1 alpha were also found on human PMN prepared from peripheral blood. There are approximately 900 receptors per cell on human PMN with a dissociation constant similar to that observed for elicited murine PMN. Binding of 125I-IL-1 alpha to the mouse and human PMN is inhibited by both recombinant human IL-1 alpha and IL-1 beta, indicating that both IL-1 proteins bind to the same receptor on these cells. Human PMN were able to internalize radioiodinated IL-1. We conclude that PMN possess receptors for IL-1 and that these binding sites may be important in mediating IL-1 effects on granulocytes that are involved in the inflammatory response.
Protein kinase C-dependent and -independent mechanisms of cloned murine T cell proliferation. The role of protein kinase C translocation and protein kinase C activity.
Authors: Kim D K , Lancki D W , Hui F H , Fitch F W
Published: December 2022

PMA can induce the proliferation of several CTL clones but not of several Th clones derived and tested in our laboratory. The PMA-stimulated proliferation of our CTL clones (which do not make IL-2 mRNA or protein) occurs independently of IL-2 and is not accompanied by lymphokine release. We now report, however, that protein kinase C (PKC) translocation is induced by PMA in CTL clones as well as in Th clones, which lack a proliferative response to PMA. These results suggest that PKC translocation itself is not a sufficient regulatory mechanism to account for cloned T cell proliferation. Moreover, IL-2 did not induce PKC translocation in a CTL clone, which proliferates when stimulated with IL-2. Thus, PKC translocation may not be necessary for activation of CTL proliferation. Nonetheless, cellular PKC activity appears to be required for the proliferative response of T cell clones after stimulation by PMA/PMA + calcium ionophore (A23187) or by triggering through the TCR: chronic PMA treatment, which depletes intracellular PKC activity, abrogates the proliferative response of T cell clones stimulated by PMA/PMA + A23187 or triggered through the TCR. T cell clones depleted of PKC activity, however, retain the ability to proliferate when challenged with IL-2. Murine T cell clones, therefore, possess PKC-dependent and PKC-independent pathways of proliferation that are not regulated by PKC translocation alone.
Dual mechanisms in priming of the chemoattractant-induced respiratory burst in human granulocytes. A Ca2+-dependent and a Ca2+-independent route.
Authors: Koenderman L , Yazdanbakhsh M , Roos D , Verhoeven A J
Published: December 2022

After interaction with so-called priming agents, the respiratory burst in human granulocytes does not become activated, but is enhanced upon subsequent stimulation with the chemoattractant FMLP. Investigating the mechanism of the priming reaction, we found that a transient rise in the cytosolic free calcium concentration [( Ca2+]i) suffices to irreversibly prime human granulocytes. Thus, platelet-activating factor (PAF) induced a transient increase in [Ca2+]i and primed the cells to an enhanced respiratory burst upon subsequent interaction with FMLP. Artificially, the transient rise in [Ca2+]i was mimicked by addition and subsequent removal of the Ca2+ ionophore ionomycin; this treatment too, primed the respiratory burst of the granulocytes. The priming induced by ionomycin was completely abolished when [Ca2+]i changes were buffered during exposure of the cells to the ionophore. The priming induced by PAF was only partially inhibited under [Ca2+]i-buffering conditions during priming, indicating that multiple pathways exist in the priming of granulocytes by PAF.
Immunosuppressive properties of electrophoretically "slow" and "fast" form alpha 2-macroglobulin. Effects on cell-mediated cytotoxicity and (allo-) antigen-induced T cell proliferation.
Authors: Petersen C M , Ejlersen E , Moestrup S K , Jensen P H , Sand O , Sottrup-Jensen L
Published: December 2022

Lymphokine activated killer cell lysis of K562 cells was inhibited by alpha 2-macroglobulin (alpha 2M), soybean trypsin inhibitor, and alpha 1-proteinase inhibitor. In serum free medium 2 mg/ml alpha 2M suppressed target cell lysis in a 4-h cytotoxic assay with about 40%. Suppression was dose and time dependent. Cytotoxicity was unaffected by alpha 2M concentrations less than 0.25 mg/ml, and by alpha 2M added later than 1.5 h from start of assay. Pre-treatment of effector (but not of target) cells with alpha 2M was even more suppressive than the presence of alpha 2M during assay. Cell-mediated cytotoxicity was not inhibited by alpha 2M treated with methylamine or by various alpha 2M-proteinase complexes. In contrast, alpha 2M-proteinase complex as well as native alpha 2M suppressed the proliferation of Ag-activated T cells. However, methylamine-treated alpha 2M did not inhibit T cell proliferation, and suppression by alpha 2M-proteinase complex was significantly reduced after inhibition of the alpha 2M-bound proteinase. On incubation at 4 degrees C with lymphokine-activated killer cells, alpha 2M reacted with cell associated proteinases and changed from electrophoretically "slow" to "fast" form. Cell associated proteinases bound by alpha 2M showed chymotrypsin- and trypsin-like specificities and their activity surpassed activity caused by cellular leakage and secretion. The present results strongly indicate that alpha 2M mediates immunosuppression in its capacity as a proteinase inhibitor and suggest inhibition of (T)cell surface-associated proteinases as a possible mode of suppression.
Selective up-regulation of endothelial cell class I MHC expression by cytokines from patients with lymphatic filariasis.
Authors: Freedman D O , Nutman T B , Jamal S , Kumaraswami V , Ottesen E A
Published: December 2022

Local host immune responses to the lymphatic-dwelling filarial parasite Wuchereria bancrofti are important in the pathogenesis of the lymphangitis that leads to filarial elephantiasis. That the lymphatic endothelial cells may be important in this inflammatory process was shown by the ability of supernatants generated from filarial Ag-driven PBMC of individuals with filarial elephantiasis caused by W. bancrofti infection to up-regulate class I MHC expression on human umbilical vein endothelial cells when compared to unstimulated control supernatants from the same individual (relative fluorescence intensity = 159% +/- 13.5; p less than 0.001). In contrast, individuals with the same filarial infection but manifesting no lymphatic disease were unable to generate, in response to filarial Ag the cytokines required for this activation (relative fluorescence intensity = 93% +/- 2.6). Supernatants induced by a non-filarial Ag (purified protein derivative) were able to effect class I MHC up-regulation in both patient groups. The same filarial Ag-driven supernatants did not cause detectable class II MHC staining on human umbilical vein endothelial cells. These results suggest a likely role for parasite Ag-driven, cytokine-mediated endothelial cell activation in the pathogenesis of lymphatic inflammatory/obstructive filarial disease.
A family of small inducible proteins secreted by leukocytes are members of a new superfamily that includes leukocyte and fibroblast-derived inflammatory agents, growth factors, and indicators of various activation processes.
Authors: Brown K D , Zurawski S M , Mosmann T R , Zurawski G
Published: December 2022

We have isolated and characterized four cDNA clones that encode mRNA expressed more abundantly in Con A-activated mouse helper T cells than by resting T cells. One mRNA encoded a approximately 14-kDa protein with a hydrophobic N-terminal sequence and was abundantly expressed by the Th 2 subset of Th cells, but was not expressed by Th 1 cells. The remaining three mRNA encoded related approximately 8-kDa secreted proteins that are part of a family of small, secreted, and inducible mouse and human proteins. This family of proteins is itself distantly related to another family of growth and inflammatory factors that are associated with various lymphoid and fibroblast activation phenomena. One of the small, inducible, secreted proteins has a predicted mature N terminus identical to that of the previously described macrophage inflammatory protein.
Signaling through T lymphocyte surface proteins, TCR/CD3 and CD28, activates the HIV-1 long terminal repeat.
Authors: Tong-Starkesen S E , Luciw P A , Peterlin B M
Published: December 2022

The state of T cell activation and proliferation controls HIV-1 replication and gene expression. Previously, we demonstrated that the administration of PHA and PMA to the human T cell line Jurkat activates the HIV-1 enhancer, which is composed of two nuclear factor kappa B (NF kappa B) binding sites. Here, we show that PMA alone is sufficient for this effect. In addition, activation of T cells through the surface proteins TCR/CD3 and CD28 increased gene expression directed by the HIV-1 long terminal repeat (LTR) to the same extent as PMA. Analysis of 5' deletions in the LTR revealed that the NF kappa B binding sites and sequences in the upstream U3 region are required for this response. Whereas cyclosporin A did not inhibit the effect of PMA, it reduced the effects of agonists to TCR/CD3 and CD28 on the LTR. H7, an inhibitor of protein kinase C (PKC), blocked the effects of all stimuli. Thus, PMA activates the NF kappa B sites through a PKC-dependent pathway while ligands to TCR/CD3 and CD28 activate the LTR through a cyclosporin A-sensitive, PKC-dependent pathway of T cell activation. We conclude that mechanisms involved in the expression of IL-2 and the alpha-chain of the IL-2R alpha genes also play a role in the regulation of HIV-1. Physiologic stimuli can activate HIV-1 gene expression; agents that block T cell activation also inhibit activation of the LTR. These observations might serve as a model for the regulation of HIV-1 gene expression in peripheral blood T cells.
Isolation and sequence of sheep Ig H and L chain cDNA.
Authors: Foley R C , Beh K J
Published: December 2022

Sheep lymphocyte poly(A+) RNA was used as a template for the enzymatic synthesis of cDNA before cloning into the expression vector lambda gt11. Screening of the cDNA library with mAb probes resulted in the isolation of two recombinant phages containing Ig coding sequences of 704 bp and 925 bp. These were inserted into the EcoRI site of pUC18 and named pSLC (sheep Ig L chain) and pSHC (sheep Ig H chain). The insert in pSLC revealed sequence homology by using GenBank to lambda L chain and pSHC revealed sequence homology to IgG sequences from various species. The L chain cDNA contained the full translation sequence and 5' and 3' nontranslating region while the H chain cDNA coded for the secreted form of IgG1 and lacked sequences upstream from the C region. The derived amino acid sequences showed significant homology with various Ig sequences already described for human, mouse, rabbit, pig, and chicken but the degree of homology showed no consistency with established phylogenetic relationships.
Thyrotropin: an endogenous regulator of the in vitro immune response.
Authors: Kruger T E , Smith L R , Harbour D V , Blalock J E
Published: December 2022

We have previously shown that thyrotropin (TSH), which is produced by lymphocytes in response to the T cell mitogen staphylococcal enterotoxin A, enhances in vitro antibody production to T cell-dependent and independent Ag (SRBC and trinitrophenylated Brucella abortus [BA-TPN], respectively) as determined by a direct plaque-forming cell assay. As a result of these studies, experiments were designed to examine the possible immunoregulatory function of thyrotropin-releasing hormone (TRH) on the in vitro antibody response to the T cell-independent Ag BA-TNP. Our studies demonstrate that TRH at very low concentrations (pM) enhances the in vitro plaque-forming cell response to BA-TNP and also induces splenocyte production of TSH. Other hypothalamic-releasing factors were without effect. This enhancement effect by TRH was specifically blocked by rabbit antisera to the TSH-beta subunit, whereas addition of normal rabbit sera had no effect. These data suggest that TRH specifically enhances the in vitro antibody response via production of immunoreactive TSH.
Co-recognition of endogenous antigens with HLA-DR1 by alloreactive human T cell clones.
Authors: Lombardi G , Sidhu S , Lamb J R , Batchelor J R , Lechler R I
Published: December 2022

The fine specificity of anti-HLA-DR1 alloreactive, human T cells was investigated by using DR1-expressing human and murine stimulator cells. All three bulk cell lines and six out of seven T cell clones proliferated in response to DR1-expressing mouse L cells. In addition to these species non specific T cells, three clones were identified which proliferated only in response to DR1 expressed by human or by murine stimulator cells. The patterns of response of these clones may reflect specificity for species or lineage-specific peptides with DR1. The results of aldehyde fixation and cytotoxicity experiments suggested that some of the T cell clones which proliferated in response to human and murine DR1 stimulators also required to recognize species-specific antigens. The responses of four of the six clones were abolished by fixation of DR1-L cells but not of a DR-1 EBV transformed lymphoblastoid cell line before co-culture. In addition, these clones were also cytotoxic for DR1-expressing human targets. The same clones which failed to recognize fixed L cells also failed to lyse DR1-L cells in a short term chromium release assay. Taken together these results suggest that some alloreactive anti-DR1, T cells are specific for peptides of cellular proteins seen in the context of the allo-MHC molecule. It is envisaged that L cells when co-cultured with human T cells, process and present peptides derived from proteins that are shed or secreted by the human cells, for co-recognition with DR1 on the L cell surface. The presentation of multiple peptides derived from endogenous proteins by allogeneic cells may contribute to the high precursor frequency of allo-reactive T cells.
Evidence that T cell activation is required for HIV-1 entry in CD4+ lymphocytes.
Authors: Gowda S D , Stein B S , Mohagheghpour N , Benike C J , Engleman E G
Published: December 2022

The relationship of T cell activation to HIV entry and generation of viral DNA intermediates was studied in freshly isolated CD4+ T lymphocytes. Unstimulated cells exposed to infectious virus for up to 48 h did not synthesize any detectable unintegrated HIV DNA duplex forms or integrated genomic provirus. However, activation of these cells with either PHA or OKT3 (anti-CD3) mAb before viral exposure resulted in the generation of unintegrated HIV DNA after 6 h and integrated copies after 24 h. Cell-to-cell fusion studies showed significantly attenuated fusion between freshly isolated resting T cells and T cells constitutively expressing high levels of HIV envelope glycoprotein (HXB/gpt) compared with T cells first stimulated with either PHA or OKT3 mAb. The baseline fusion observed with resting T cells is believed to be a consequence of allogeneic stimulation by the HXB/gpt cell line. These results provide evidence that HIV entry and HIV envelope-dependent cell-to-cell fusion require T cell activation.
Regulation of hemopoiesis in myelosuppressed mice by human recombinant IL-1 alpha.
Authors: Benjamin W R , Tare N S , Hayes T J , Becker J M , Anderson T D
Published: December 2022

Human rIL-1 alpha was shown to be a potent stimulus of granulopoiesis in mice that have been myelosuppressed with cyclophosphamide. Stimulation of granulopoiesis was demonstrated in IL-1-treated mice by an accelerated recovery of granulocyte-macrophage colony-forming cells, bone marrow and splenic granulocytic hyperplasia, and a profound granulocytosis. Granulopoiesis was stimulated by IL-1 in a dose-dependent manner at doses ranging from 0.5 to 50 micrograms/kg. Maximal increases in granulocytes were observed after 4 days of IL-1 treatment. Mice treated with IL-1 also exhibited increased splenic megakaryopoiesis with a resultant increase in the number of peripheral blood platelets. In contrast to these positive effects on hemopoiesis, bone marrow, but not splenic, erythropoiesis was depressed in IL-1-treated mice. IL-1 effects were observed in mice treated with a wide dose range (50 to 300 mg/kg) of cyclophosphamide, with optimal effects occurring at a dose of 200 mg/kg. The doses of IL-1 leading to enhanced granulopoiesis caused only minor and transient changes in selected clinical chemistry parameters and caused no toxicities that were evident by histologic examination of tissues. The stimulation of granulopoiesis in the absence of overt toxicity suggests that IL-1 may be useful clinically to enhance the recovery of granulocytes in myelosuppressed patients.
A rabbit antiserum detects a VH J558 subgroup marker highly expressed among anti-alprenolol antibodies.
Authors: Nahmias C , Cazaubon S , Strosberg A D
Published: December 2022

A rabbit antiserum raised against anti-alprenolol mAb 14C3 detects common antigenic determinants (ADC3) in 10 out of 14 anti-alprenolol mAb that use different germ-line VH and/or Vk genes. The anti-14C3 antiserum binds only to H chains in immunoblots, therefore suggesting that at least part of the ADC3 determinants may be encoded by H chain V region genes. Analysis of VH gene family usage among the anti-alprenolol mAb reveals that the expression of ADC3 correlates with utilization of VH genes that belong to the J558 gene family, regardless of the JH, Vk, and Jk genes. To determine whether the ADC3 determinants are general V region markers or whether they are unique to anti-alprenolol antibodies, we have extended our analysis to a random panel of antibodies that also use VH genes of the J558 family. Among 23 mAb of various specificities, 14 react with the anti-14C3 antiserum in immunoblot and in ELISA, irrespective of antibody specificity. Adsorption of the antiserum on one of these positive antibodies results in a loss of reactivity toward both anti-alprenolol and unrelated antibodies. Therefore, several but not all antibodies that use a J558 VH gene also express the complete set of epitopes defining ADC3. These results strongly suggest that ADC3 are markers of a subset of J558 VH gene products. The anti-14C3 antiserum may thus constitute a "serologic probe" for identification of a VH gene subgroup from the J558 gene family.
Autoimmune mice and stimulated normal mice make lambda 1 with increased V region diversity.
Authors: Slack J H , Hang L , Amundson C , Clevinger B L , Dixon F J
Published: December 2022

Previous studies of the genetic bases of murine SLE have defined gene segments that encode the H chain and the kappa L chain of anti-DNA, anti-Sm, and anti-IgG autoantibodies. As a result of these studies, the genetic origins of autoantibody H chains and kappa L chains are better understood, but little remains known about the genetic bases of autoantibody lambda-chains. Thus, we have analyzed serologically the germ-line and somatic origins of lambda 1 L chains in antibodies of normal mice and in both antibodies and autoantibodies of autoimmune mice. This study finds an increased lambda 1 diversity in both Ag-stimulated mice and autoimmune mice. This study also finds that the lambda 1 L chains in antibodies of unstimulated normal mice have the gene segment-encoded variable region, V lambda 1. In contrast, additional genetic processes appear to make the lambda 1 V regions of antibodies in Ag-stimulated normal mice and the lambda 1 V regions of both antibodies and autoantibodies in autoimmune mice. The increased lambda 1 diversity that we found in both Ag-stimulated mice and autoimmune mice might be caused by mutational processes creating antibody diversities. Therefore, the same somatic processes might be able to make both antibody and autoantibody lambda 1 diversities.
Impact of genetically regulated T cell proliferation on acquired resistance to Listeria monocytogenes.
Authors: Berche P , Decreusefond C , Theodorou I , Stiffel C
Published: December 2022

Two lines of mice genetically selected for high and low in vitro responses to PHA were used to evaluate the impact of T cell polyclonal expansion on acquired resistance to Listeria monocytogenes. The selective breeding induced two major consequences in low responder mice: (1) a reduction of the number of L3T4+ cells and (2) a restriction of T cell expansion upon PHA stimulation, predominantly affecting the Lyt-2+ subset, and associated with an abridgment of IL-2 production. In vivo PHA stimulation induced anti-Listeria protection in high responder mice, but was much less effective in low responder mice. Flow cytometer analysis revealed that T cell proliferation was also reduced in low responder mice during the course of Listeria infection, implying both L3T4+ and Lyt-2+ subsets. This defect did not apparently influence the kinetics of bacterial elimination in host tissues, which was similar in both lines during primary Listeria infection. In contrast, the expression of delayed-type hypersensitivity to Listeria antigens and the level of immunologic memory were significantly reduced in low responder mice. In vivo selective T cell depletion by anti-L3T4 or anti-Lyt-2 mAb allowed us to demonstrate the predominant role of Lyt-2+ cells in protection and that of L3T4+ cells in the expression of delayed-type hypersensitivity.
Isolation of a yeast heptaglucoside that inhibits monocyte phagocytosis of zymosan particles.
Authors: Janusz M J , Austen K F , Czop J K
Published: December 2022

To isolate a unit ligand recognized by human monocyte beta-glucan receptors, acid-solubilized oligoglucosides were prepared by partial acid hydrolysis of purified yeast cell walls, gel filtered sequentially on Bio-Gel P-4 and P-2, derivatized with 2-aminopyridine, and separated by normal-phase HPLC. Ligand recognition was assessed by quantitating the effect of pretreatment with isolated materials on the capacities of adherent monocytes to phagocytose zymosan particles. Partial acid hydrolysis solubilized 23 +/- 4% (mean +/- SD; n = 7) of the cell wall glucans; at an input of 50 micrograms/ml, the solubilized products reduced the numbers of monocytes ingesting zymosan by an average of 44%. Gel filtration of acid-solubilized glucans on Bio-Gel P-4 revealed several peaks with phagocytosis-inhibiting activity, and fractions from the peak containing the smallest oligoglucosides, which accounted for 10 +/- 2% (mean +/- SD; n = 7) of the carbohydrate applied, were pooled. Further purification on Bio-Gel P-2 resolved this phagocytosis-inhibiting activity to a single peak that contained apparent heptaoses and accounted for 8 +/- 2% (mean +/- SD; n = 6) of the carbohydrate applied. At a concentration of 0.5 microgram/ml, the oligoglucosides pooled from the Bio-Gel P-4 and P-2 columns reduced the numbers of ingesting monocytes by 45 +/- 1% and 42 +/- 7% (mean +/- SD; n = 3), respectively. When derivatized with 2-aminopyridine, the oligoglucosides were resolved by HPLC to a number of peaks; a peak that eluted as an apparent heptaglucoside contained virtually all the inhibitory activity and accounted for only 6.6 +/- 0.7% (mean +/- SD, n = 7) of the carbohydrate applied. Gas chromatography analysis revealed only glucose and FAB-mass spectrometric analysis showed only heptaglucoside and no noncarbohydrate molecules. At a concentration of 1.6 ng/ml, the derivatized yeast heptaglucoside reduced the numbers of monocytes ingesting zymosan and glucan particles by 44 +/- 9% (mean +/- SD; n = 5) and 45 +/- 6% (n = 3), respectively. Thus, a heptaglucoside present in yeast cell walls is a unit ligand for human monocyte beta-glucan receptors.
The molecular basis of granuloma formation in schistosomiasis. II. Analogies of a T cell-derived suppressor effector factor to the T cell receptor.
Authors: Perrin P J , Prystowsky M B , Phillips S M
Published: December 2022

During Schistosoma mansoni infection, Ts cells regulate granulomatous modulation via antigenically and genetically restricted suppressor inducer and suppressor effector factors. The T suppressor effector factor (TseF) directly suppresses granuloma formation both in vitro and in vivo. In this study, we probe the molecular basis of these TseF properties. Using techniques of heterodimeric chain reduction with DTT and in vitro functional complementation, chimeric molecules were constructed. By analyzing genetic restrictions, antigenic specificities, and phenotypic markers, the contributions of the component chains to 72 kDa TseF reactivity were determined. One chain bore an Ag receptor and imparted antigenic specificity. The other chain bore an IJ determinant, a TCR beta-chain allotypic determinant, a suppressor effector phenotypic determinant, and imparted functional genetic restriction. Functional activity required covalent, probably sulfhydryl mediated, linkage as succinylation prevented the separated component chains from reconstituting functional activity. Additional studies demonstrated that anti-serum directed against either the T cell receptor or the T3 epsilon-chain could abrogate functional activity. However, TseF bore no T3 epsilon-chain phenotypic marker per se suggesting that TseF effects T lymphocytes via transmembrane signal transduction. These studies suggest that a regulatory network is operative in granuloma modulation. This regulatory network is mediated by a soluble TseF that bears significant structural homologies to the classic TCR.