bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of B lymphocyte development and activation by the CD19/CD21/CD81/Leu 13 complex requires the cytoplasmic domain of CD19.
Authors: Sato S , Miller A S , Howard M C , Tedder T F
Published: December 2022

B lymphocyte development and function are regulated in part by the CD19 cell surface receptor complex, which is composed of at least four proteins; CD19, CD21 (CR2, complement receptor 2), CD81, and Leu 13. Because this complex has eight membrane-spanning domains and six cytoplasmic regions, determining the molecular basis for its function and signal transduction activities has not been straightforward. In this study, the contribution of the CD19 cytoplasmic domain to the in vivo function of the CD19/CD21/CD81/Leu 13 complex was assessed by generating CD19-deficient mice that expressed a transgene that encoded only the extracellular and transmembrane domains of CD19. Mice expressing this transgene were similar, if not identical, to CD19-deficient mice with abnormal B cell development, a lack of B-1 cells, increased surface IgM levels on B cells, modest mitogen responses, minimal serum Ig levels, and low humoral immune responses. The results of this study indicate that specific signals generated through the cytoplasmic domain of CD19 are essential for B lymphocyte development and function, and that CD19 is the dominant signaling component of the CD19 complex. Moreover, expression of the CD19 cytoplasmic domain is required for optimal signaling through the B cell Ag receptor complex.
Cytotoxic activities of recombinant soluble murine lymphotoxin-alpha and lymphotoxin-alpha beta complexes.
Authors: Mackay F , Bourdon P R , Griffiths D A , Lawton P , Zafari M , Sizing I D , Miatkowski K , Ngam-ek A , Benjamin C D , Hession C , Ambrose C M , Meier W , Browning J L
Published: December 2022

Human lymphotoxin-alpha (LT alpha) is found in a secreted form and on the surface of lymphocytes as a complex with a second related protein called lymphotoxin-beta (LT beta). Both secreted human LT alpha and TNF have similar biological activities mediated via the TNF receptors, whereas the cell surface LT alpha beta complex binds to a separate receptor called the LT beta receptor (LT beta R). The murine LT alpha and LT beta (mLT alpha and mLT beta) proteins have never been characterized. When recombinant mLT alpha was produced by either of several methods, the protein had a very low specific activity relative to that of human LT alpha in the conventional WEHI 164 cytotoxicity bioassay. The weak activity observed was inhibited by a soluble murine TNF-R55 Ig fusion protein (mTNF-R55-Ig), but not by mLT beta R-Ig. Coexpression of both mLT alpha and a soluble version of mLT beta in insect cells led to an LT alpha beta form that was cytotoxic in the WEHI 164 assay via the LT beta R. To determine whether natural mLT alpha-like forms with cytotoxic activity comparable to that of secreted human LT alpha were secreted from primary spleen cells, splenic lymphocytes were activated in various ways, and their supernatants were analyzed for cytotoxic activity. Using specific Abs to distinguish between mTNF and mLT, a TNF component was readily detected; however, there was no evidence for a secreted mLT alpha cytotoxic activity using this assay. Combined, these observations suggest that secreted mLT alpha may not play a role in the mouse via interactions with TNF-R55, and the ramifications of this hypothesis are discussed.
TCR-delta gene rearrangement and selection during fetal thymocyte development.
Authors: Wilbert O M , Weber-Arden J , Kabelitz D , Arden B
Published: December 2022

TCR delta-chain gene rearrangements were analyzed at different stages of thymic ontogeny. The VDJ delta junctional sequences of the dominantly expressed TCR delta-chain V7 subfamily are highly conserved in fetal and neonatal thymocytes. They are equally conserved in C delta-targeted mice lacking cell surface expression of gamma delta receptors, indicating evolutionary selection acting at the level of DNA rearrangement. Yet, in C delta-mutant mice, the frequency of in-frame transcripts is reduced to 61%, from 88% in wild-type mice, suggesting cellular selection of this DV7-overexpressing gamma delta thymocyte subset. In contrast, in genomic DNA rearrangements, no difference was found in the frequency of productive rearrangements between mutant (26%) and wild-type mice (31%). This in-frame rate, characteristic of random rearrangements, indicates that positive selection is not required for thymic maturation of gamma delta T cells. The results are discussed with regard to models of alpha beta/gamma delta lineage commitment.
Position-dependent variegation of a CD4 minigene with targeted expression to mature CD4+ T cells.
Authors: Boyer O , Zhao J C , Cohen J L , Depetris D , Yagello M , Lejeune L , Bruel S , Mattéï M G , Klatzmann D
Published: December 2022

The CD4 gene follows a complex and highly regulated pattern of expression throughout T cell development. This expression is governed by different regulatory elements that have been partly identified, including a promoter, a proximal enhancer, and a silencer. Here we show that a CD4 minigene comprising a combination of these elements is specifically expressed in mature CD4+ T cells of transgenic mice, but not in CD4+CD8+ double positive thymocytes. The proportion of transgene-expressing CD4+ T cells was constant within a given transgenic line, but varied greatly from one line to another. We demonstrate that this pattern of expression is due to integration of the transgene within or in the vicinity of centromeric heterochromatin. This position-effect variegation demonstrated with a short CD4 transgene has not been observed with larger ones containing additional regulatory sequences, suggesting that the CD4 gene contains a locus control region. Such position-dependent effects must be taken into consideration when developing transgenic models or gene transfer vectors because they can result in the absence of transgene expression in a subpopulation of target cells. Finally, the combination of the CD4 gene silencer, proximal enhancer, and promoter provides an interesting tool to selectively express genes of interest in mature CD4+ T cells of transgenic mice and for the development of gene therapy vectors.
IFN-gamma is not required in the IL-12 response to vesicular stomatitis virus infection of the olfactory bulb.
Authors: Komatsu T , Reiss C S
Published: December 2022

In this report, the role of IFN-gamma in host defense to exogenous IL-12 and clearance of vesicular stomatitis virus (VSV) from the central nervous system was examined. Wild-type and IFN-gamma knockout mice infected with VSV were treated with IL-12 or medium. In both groups, IL-12 treatment resulted in 1) substantially decreased VSV titers in brain homogenates and diminished immunohistochemical detection of VSV Ags in tissue sections; 2) induction of types 1, 2, and 3 nitric oxide synthase; and 3) induction of MHC molecules and rapid infiltration of both T cells and NK cells. These results suggest that IFN-gamma production, both systemically and in the olfactory bulb, contributes to but is not essential for clearance of VSV from the brain. Neutralization of TNF-alpha in IFN-gamma knockout mice mice treated with IL-12 was accompanied by the same immunohistochemical changes, implying that neither IFN-gamma nor TNF-alpha was required. In vitro studies using purified IL-12 or IFN-gamma in culture medium induced nitric oxide synthase isoforms in neurons, glia, and macrophages, and MHC II on glia and macrophages. These data suggest that IL-12 directly activates neurons to promote viral clearance in vivo.
CD28/B7 interactions are required for sustaining the graft-versus-leukemia effect of delayed post-bone marrow transplantation splenocyte infusion in murine recipients of myeloid or lymphoid leukemia cells.
Authors: Blazar B R , Taylor P A , Boyer M W , Panoskaltsis-Mortari A , Allison J P , Vallera D A
Published: December 2022

Graft-vs-leukemia (GVL) can reduce relapse rates after bone marrow transplantation (BMT). Delayed lymphocyte infusion (DLI) post-BMT can mediate a potent GVL effect with less graft-vs-host disease (GVHD) than would be observed if given early post-BMT. In vivo CD28/B7 blockade can reduce GVHD lethality, and B7 ligand expression can augment an antitumor immune response in mice. To examine the role of CD28/B7 interactions in DLI-mediated GVL, we established murine allogeneic BMT models in C57BL/6 (B6) recipients of C1498 (B6 acute myeloid leukemia) or EL4 (B6 acute T cell leukemia) that closely mimic human GVL. Recipients of C1498 and DLI had a marked reduction in relapse. GVL was blocked by anti-B7 mAb infusion. In contrast, recipients of EL4 cells and B10.BR DLI had a more modest GVL effect. The forced expression of B7-1 on EL4 cells markedly augmented the GVL effect of DLI, in contrast to the forced expression of B7-2 on EL4 cells. Relapse rates observed in recipients of C1498-B7-1 and DLI were significantly lower than in recipients of parental C1498 cells. We conclude that the administration of anti-B7 mAbs may impair the GVL effect of DLI and that the forced expression of B7-1 ligands stimulates a GVL effect without adversely affecting the GVHD lethality effect of DLI.
Interaction of IgA with Fc alpha receptors of human mesangial cells activates transcription factor nuclear factor-kappa B and induces expression and synthesis of monocyte chemoattractant protein-1, IL-8, and IFN-inducible protein 10.
Authors: Duque N , Gómez-Guerrero C , Egido J
Published: December 2022

The mechanisms of glomerular damage in IgA nephropathy remain undefined. Mesangial cells (MC) possess Fc receptors for IgA (Fc alpha R), and their occupancy triggers cytokine expression, cell proliferation, and extracellular matrix synthesis. In cultured human MC we examined the effects of soluble IgA aggregates (AIgA) on the activation of nuclear factor-kappa B (NF-kappa B) and the production of proinflammatory chemokines monocyte chemoattractant protein-1 (MCP-1), IL-8, and IFN-inducible protein-10 (IP-10). The exposure of MC to AIgA rapidly activated a NF-kappa B complex constituted of p50 and p65 subunits. NF-kappa B activation was dose dependent, abolished by preincubation with IgA Fc fragments (indicating that AIgA effects occur via specific Fc alpha R), and attenuated by kinase inhibitors. MC stimulation with AIgA increased the mRNA expression of MCP-1, IL-8, and IP-10 in a time- and dose-dependent manner. Maximal expression of IL-8 was observed at 3 h (4.5-fold), while IP-10 and MCP-1 peaked at 6 h (5-fold for both). AIgA also induced biosynthesis and release of the chemokines, which presented biological activity in neutrophil and monocyte chemoattractant assays, peaking at 6 and 9 h, respectively. MC pretreatment with the antioxidant pyrrolidine dithiocarbamate inhibited NF-kappa B activation and chemokine mRNA expression. This study shows that stimulation of Fc alphaR in MC induces gene expression of MCP-1, IL-8, and IP-10, a process partially mediated by NF-kappa B activation. These data may be of importance for a better understanding of the pathogenesis of glomerular damage in IgA immune complex-related diseases.
IL-12 induces IFN-gamma expression and secretion in mouse peritoneal macrophages.
Authors: Puddu P , Fantuzzi L , Borghi P , Varano B , Rainaldi G , Guillemard E , Malorni W , Nicaise P , Wolf S F , Belardelli F , Gessani S
Published: December 2022

We previously reported that resting mouse peritoneal macrophages (PM) constitutively express low levels of IFN-gamma, whose production is consistently enhanced by exogenous IFN-gamma. In this study, we investigated the effects of IL-12 on the replication of vesicular stomatitis virus and on IFN-gamma gene expression in mouse PM. The addition of IL-12 to freshly explanted PM resulted in the persistence of an antiviral state to vesicular stomatitis virus, while control PM progressively became permissive for virus replication after 3 to 4 days in culture. The IL-12-induced antiviral state was inhibited by Abs to IFN-gamma, suggesting that endogenous IFN-gamma was largely responsible for this antiviral response. Moreover, IL-12 induced a consistent secretion of IFN-gamma, especially in cultured PM. The IL-1 2-induced antiviral state and IFN-gamma production were observed using PM from various strains of mice, including LPS-defective C3H/HeJ, NK-deficient bg/bg, DBA/2, Swiss (CD1), and Swiss nude mice treated or not with anti-asialo GM1 Abs. A 4-h treatment with IL-12 was sufficient to induce a marked accumulation of IFN-gamma mRNA, which was greater in cultured PM than in freshly harvested cells. Lastly, immunofluorescence studies in IL-12-stimulated macrophages clearly showed an enhancement of immunoreactive IFN-gamma compared with basal levels in cells exhibiting a macrophage (i.e., F4/80-positive) phenotype. Together, these findings demonstrate that IL-12 can directly stimulate mouse PM to produce IFN-gamma. We suggest that IL-12-induced IFN-gamma production by macrophages can play some role in the generation of the antiviral and immunoregulatory effects of IL-12.
Comparison of E-selectin-binding glycoprotein ligands on human lymphocytes, neutrophils, and bovine gamma delta T cells.
Authors: Jones W M , Watts G M , Robinson M K , Vestweber D , Jutila M A
Published: December 2022

We compared E-selectin-binding cell surface ligands on bovine gamma delta T cells and human leukocytes using an E-selectin/Ig chimera. The chimera worked well in flow cytometric studies and showed that bovine gamma delta T cells were the only lymphocyte population in newborn animals that bound E-selectin chimera. Furthermore, the chimera blocked gamma delta T cell rolling on E-selectin. Chimera reacted with four potential glycoprotein ligands of 180, 200, 250, and 300 kDa in Western blot analysis of gamma delta T cell detergent lysates, and it specifically precipitated at least two of these E-selectin ligands (200 and 250 kDa) from lysates of cell surface biotinylated gamma delta T cells. Preclearing bovine gamma delta lysates of GD3.5 Ag and workshop cluster 1 did not abrogate E-selectin ligand precipitation, suggesting that these surface markers do not represent E-selectin ligands. Human neutrophils possessed three E-selectin-binding ligands of approximately 80 to 90, 130, and 230 kDa, while human lymphocytes variably possessed three ligands of 120, approximately 220 to 240, and 260 kDa. Cross-precipitation experiments confirmed the results of others that neutrophil L-selectin serves as the 80 to 90-kDa E-selectin ligand. The human lymphocyte approximately 220 to 240-kDa and 260-kDa ligands may be analogous to the bovine gamma delta T cell molecules, whereas the 120-kDa is unique to human cells. The identities of the human and bovine lymphocyte E-selectin ligands are unknown. Finally, E-selectin ligand-1 apparently may have a minimal role, if any, in lymphocyte/E-selectin interactions, since a polyclonal anti-E-selectin ligand-1 serum stained a minimal number of cutaneous lymphocyte-associated Ag-positive human lymphocytes and bovine gamma delta T cells.
TGF-beta production regulates the development of the 2,4,6-trinitrophenol-conjugated keyhole limpet hemocyanin-induced colonic inflammation in IL-2-deficient mice.
Authors: Lúdvíksson B R , Ehrhardt R O , Strober W
Published: December 2022

A severe, Th1-mediated experimental colitis with similarities to inflammatory bowel disease in humans can be induced by a single injection of 2,4,6-trinitrophenol (TNP)-substituted protein plus adjuvant in IL-2-/- mice. To determine the early events involved in the pathogenesis of IL-2-/-colitis, we compared the function of lamina propria (LP) T cells from IL-2-/- and IL-2+/+ mice subjected to disease-inducing (TNP-conjugated keyhole limpet hemocyanin [TNP-KLH]) and disease-inhibiting (anti-CD3) immunization protocols. We show that LP T cells in TNP-KLH-immunized IL-2-/- mice fail to produce TGF-beta early (day 2), whereas LP T cells in TNP-KLH-immunized IL-2+/+ mice exhibit an approximately eightfold rise in TGF-beta secretion. The critical importance of local TGF-beta production was further substantiated by the following findings. 1) LP T cells from TNP-KLH-immunized IL-2-/- mice administered anti-CD3 (i.p.) exhibit a significant rise in TGF-beta, production but fail to produce IFN-gamma, and such mice do not develop colitis. 2) TNP-KLH-immunized IL-2-/- mice administered anti-CD3 and coadministered anti-TGF-beta mAb again give rise to IFN-gamma-producing LP cells, and such mice develop colitis. 3) TNP-KLH-immunized IL-2+/+ mice administered anti-TGF-beta mAb exhibit pockets of mononuclear cell infiltrates in the LP. These results indicate that the disposition of IL-2-/- mice to develop chronic colonic inflammation is due to a Th1 cell response in the LP that is not appropriately counter-regulated by the production of the suppressor cytokine, TGF-beta.
Specificity for in vivo graft prolongation in gamma delta T cell receptor+ hybridomas derived from mice given portal vein donor-specific preimmunization and skin allografts.
Authors: Gorczynski R M , Chen Z , Zeng H , Fu X M
Published: December 2022

gamma delta TCR+ hybridoma cells prepared from mesenteric lymph node cells of animals receiving donor-specific immunization via the portal vein can adoptively transfer this increased graft survival to naive animals. Analysis of TCR gamma-chain junctional sequence diversity suggested that some 40 to 50% of the hybridomas expressed gamma-chain junctional sequence diversity and were stimulated to produce cytokines both by heat shock proteins and by minor histocompatibility Ag-specific irradiated peritoneal cells. The remaining gamma delta TCR+ hybridoma cells expressed TCR with a common gamma-chain junctional sequence and were stimulated to cytokine production by MHC-matched, but minor histocompatibility Ag-mismatched (as well as matched), peritoneal cells, but not by heat shock proteins. We have compared the effectiveness of representative hybridomas expressing unique gamma-chain junctional sequences or common gamma-chain junctional sequences for prolongation of donor-specific or third-party (MHC-matched or MHC-mismatched) skin grafts. Our data show a good correlation between the specificity for stimulation for cytokine production in vitro and efficacy in graft prolongation assays in vivo. Hybridoma cells expressing unique gamma-chain junctional sequences that showed Ag-specific stimulation of cytokine production in vitro and skin graft survival in vivo augmented survival of third-party skin grafts if simultaneously transplanted with both Ag-specific and third-party skin grafts. Graft prolongation in vivo using cells from either population of gamma delta TCR+ hybridomas was decreased by infusion of anti-IL-10 mAb and abolished when both anti-IL-10 and anti-TGF-beta Abs were used together.
Intracellular routes and selective retention of antigens in mildly acidic cathepsin D/lysosome-associated membrane protein-1/MHC class II-positive vesicles in immature dendritic cells.
Authors: Lutz M B , Rovere P , Kleijmeer M J , Rescigno M , Assmann C U , Oorschot V M , Geuze H J , Trucy J , Demandolx D , Davoust J , Ricciardi-Castagnoli P
Published: December 2022

Immature dendritic cells (DC) use both macropinocytosis and mannose receptor-mediated endocytosis to internalize soluble Ags efficiently. These Ags are ultimately presented to T cells after DC maturation and migration into the lymph nodes. We have previously described the immortalized myeloid cell line FSDC as displaying the characteristics of early DC precursors that efficiently internalize soluble Ags. To describe the different routes of Ag uptake and to identify the Ag retention compartments in FSDC, we followed the intracellular fate of FITC-coupled OVA, dextran (DX), transferrin, and Lucifer Yellow using flow cytometry, confocal microscopy, and immunoelectron microscopy. OVA and DX gained access into macropinosomes and early endosomes. DX was preferentially sorted into endosomal compartments, while most of the OVA entered macropinosomes via fluid phase uptake. We found a long-lasting retention of DX and OVA of up to 24 h. After 6 h of chase, these two molecules were concentrated in common vesicular compartments. These retention compartments were distinct from endosomes and lysosomes; they were much larger, only mildly acidic, and lacked the small GTP binding protein rab7. However, they were positive for lysosome-associated membrane protein-1, the protease cathepsin D, and MHC class II molecules, thus representing matured macropinosomes. These data suggest that the activity of vacuolar proteases is reduced at the mildly acidic pH of these vesicles, which explains their specific retention of an Ag. The retention compartments might be used by nonlymphoid tissue DC to store peripheral Ags during their migration to the lymph node.
The epithelial cell-specific integrin, CD103 (alpha E integrin), defines a novel subset of alloreactive CD8+ CTL.
Authors: Hadley G A , Bartlett S T , Via C S , Rostapshova E A , Moainie S
Published: December 2022

The interaction of CD8+CTL with epithelial layers is an important but poorly defined aspect of organ allograft rejection. We herein report that CD103 (formerly alpha E integrin), a known receptor for the epithelial cell-specific ligand E-cadherin, is expressed by a major subset of CD8 + CTL elicited in response to allogeneic renal epithelial cells (REC). In contrast, CD103 was expressed poorly on CD8 + CTL generated in the conventional manner by stimulation with allogeneic leukocytes, although expression could be dramatically up-regulated by supplementing cultures with REC or exogenous TGF-beta 1. That TGF-beta controls the expression of CD103 on CD8+ CTL was further supported by the capacity of anti-TGF-beta mAb to block the generation of such cells in anti-REC cultures. Clonal analyses of anti-REC cultures revealed that individual CD8+ CTL clones were discretely CD103+ or CD103-, nd maintained their respective phenotypes independently of the cell type used for clonal restimulation. In a mouse model of graft-vs-host disease, 16.4 +/- 2.7% of CD8 cells that infiltrated host kidneys were CD103+ (n = 4). CD8 kidney-infiltrating lymphocytes were predominantly of donor origin and displayed an activated/memory phenotype (CD62L-, CD44high), consistent with expression of CD103 on a CD8 effector subset elicited in vivo following allogeneic transplantation. Taken together, the present data demonstrate that CD103 identifies a novel CD8 effector subset and, moreover, that such cells may comprise a significant component of the response to allogeneic tissues. The potential for CD103+ CTL as an important effector mechanism in organ allograft rejection, and more generally, as a mechanistic basis for tissue-specific immune phenomena, is discussed.
Maintenance of clonotype specificity in CD95/Apo-1/Fas-mediated apoptosis of mature T lymphocytes.
Authors: Hornung F , Zheng L , Lenardo M J
Published: December 2022

Ag-induced mature T cell apoptosis is the result of death-inducing cytokines, including the ligand for CD95 (Apo-1/Fas). This raises the possibility that expression of this death molecule could affect bystander T cells that were not directly antigenically stimulated but that express the CD95 receptor. We show here that bystander T cells, even if they express the CD95 receptor, are not killed when exposed to T cells undergoing Ag-induced apoptosis. Rather, cell death is restricted to T cells that bear the receptor clonotype that is specifically engaged by TCR ligands. At least one mechanism of clonotype restriction is a significant enhancement of CD95-induced apoptosis by TCR ligation. Our results demonstrate that, in addition to the well-known ability of TCR to stimulate apoptosis by inducing CD95 ligand expression, TCR signals at the time of CD95 engagement can effectively increase apoptosis. Therefore, we put forward the hypothesis that strict clonotype specificity is preserved when death cytokines such as CD95 ligand induce autoregulatory mature T cell apoptosis, at least in part through a sensitization signal provided by the TCR stimulation.
Cytokines promote glomerular mesangial cell survival in vitro by stimulus-dependent inhibition of apoptosis.
Authors: Mooney A , Jobson T , Bacon R , Kitamura M , Savill J
Published: December 2022

Resolution of glomerular inflammation requires the removal of proliferating resident glomerular mesangial cells, but excessive loss of glomerular cells is a feature of postinflammatory scarring. Because apoptosis regulates mesangial cell number in glomerular inflammation, we have studied the exogenous control of apoptosis triggered in cultured mesangial cells by stimuli likely to be important in vivo. Apoptosis could be induced by serum deprivation to model decreased availability of survival factors, by etoposide as an example of DNA-damaging agents, by ligation of mesangial cell Fas, and by protein synthesis inhibition by cycloheximide. Insulin-like growth factor I (IGF-I), IGF-II, and basic fibroblast growth factor were each able to suppress apoptosis induced by serum deprivation, whereas TGF-beta 1, epidermal growth factor, and platelet-derived growth factor had no effect. IGF-I and IGF-II (but not basic fibroblast growth factor) were also able to protect cells from apoptosis induced by etoposide or cycloheximide. However, Fas-mediated apoptosis was resistant to suppression by all three cytokines. None of the cytokines tested caused a change in the levels of expression of Bcl-2, Bax, Bcl-x, or Bak proteins. The survival-promoting properties of serum-free medium conditioned by mesangial cells was abrogated by neutralizing IGF-I Ab. These experiments are the first to define cytokines that inhibit apoptosis and thereby promote survival of mesangial cells, and the data indicate a paracrine survival signaling role for IGF-I. Finally, the data show that Fas ligation can override cytokine survival signaling, emphasizing a candidate role for this molecule in the undesirable apoptotic loss of mesangial cells during the progression of glomerular scarring.
IL-18 accounts for both TNF-alpha- and Fas ligand-mediated hepatotoxic pathways in endotoxin-induced liver injury in mice.
Authors: Tsutsui H , Matsui K , Kawada N , Hyodo Y , Hayashi N , Okamura H , Higashino K , Nakanishi K
Published: December 2022

When LPS is administered to heat-killed Propionibacterium acnes-primed BALB/c nude mice, they develop endotoxin-induced liver injury. As previously reported, this liver injury can be prevented by treatment with an Ab against IL-18, a novel cytokine with the ability to induce IFN-gamma production and up-regulate functional Fas ligand (FasL) expression. To identify the pathologic role of IL-18 in this liver injury, we investigated the hepatic cytokine network and FasL induction after LPS challenge. After LPS challenge to BALB/c nude mice, their livers expressed IL-12 mRNA, followed by the induction of IFN-gamma and FasL mRNA and then by the late elevation of TNF-alpha mRNA, but stably expressed IL-18 mRNA. The TNF-alpha induction curve had two peaks. The first peak was the result of the direct reaction to LPS, and the late peak might have been induced, since P. acnes-elicited Kupffer cells showed one-peak TNF-alpha kinetics in response to LPS stimulation in vitro. LPS-activated P. acnes-elicited Kupffer cells secreted both IL-12 and IL-18, as determined by ELISA and bioassay, respectively. The in vivo administration of anti-IL-18 just before an LPS challenge suppressed not only the induction of IFN-gamma and the late TNF-alpha elevation, but also the FasL induction, resulting in the total prevention of liver injury, whereas such an anti-IL-12 treatment did not. Anti-IFN-gamma treatment reduced the late increase in TNF-alpha, but not FasL, resulting in a partial prevention of the liver injury. The administration of anti-TNF-alpha just before elevation of the late TNF-alpha peak also markedly, but incompletely, suppressed the LPS-induced liver injury. These data suggested that IL-18 activates both TNF-alpha- and FasL-mediated hepatocytotoxic pathways in endotoxin-induced liver injury.
Differential regulation of mast cell function by IL-10 and stem cell factor.
Authors: Lin T J , Befus A D
Published: December 2022

In the development of rodent mast cells (MC), IL-10 significantly enhances the growth factor activity of stem cell factor (SCF). The differential effects of IL-10 and SCF on function of rat peritoneal MC (PMC) are investigated in this study. IL-10 inhibits both constitutive and Ag-induced nitric oxide production by PMC in a dose-dependent manner, whereas SCF does not affect nitric oxide production by PMC. Short term (20-min) incubation with IL-10 does not affect Ag-induced histamine secretion, whereas long term (24-h) incubation with IL-10 significantly potentiates Ag-induced histamine secretion, an effect similar to those reported for IL-3 and IL-4 in mouse MC. By contrast, SCF significantly potentiates Ag-induced histamine secretion in both short term (20-min) and long term (24-h) experiments. Both constitutive and Ag-induced TNF-alpha production by PMC are dose-dependently inhibited by IL-10, whereas they are not affected by SCF at all doses tested (2-500 ng/ml) and incubation times observed (3-24 h). Interestingly, rat PMC constitutively express IL-10 mRNA and proteins, as tested by reverse transcription-PCR and immunocytochemistry. In addition, it was found by flow cytometry that 23.5% PMC express surface IL-10. Moreover, treatment of PMC with anti-IL-10 Ab for 6 h significantly potentiates constitutive and Ag-induced TNF-alpha production by rat PMC. Thus, IL-10 and SCF exert different regulatory effects on MC secretory function. IL-10 produced by MC has the potential to regulate MC function in an autocrine manner, an effect that may be highly relevant to responses involving MC activation.
The Mode of Action of Formaldehyde on Complement Fixation Systems
Authors: Reyner C. E.
Published: December 2022

The action of formaldehyde in intensifying and in accelerating the fixation of complement has been shown in studies previously reported (1, 2 and 3). Not only is this sensitizing action of formaldehyde exhibited in specific systems in which the antigenic component is formed, such as the bacterial cell, but it also is manifest in the non-specific Wassermann system in which the antigen is composed of unformed materials. With the formaldehyde in appropriate concentrations the sensitizing action is specific, but the nature of the change induced by the formaldehyde has not been entirely clear, and a study of the mode of action necessitates the use of specific antigens rather than the use of antigenic systems as employed in the Wassermann reaction. To this end, studies along various lines have been made and the work here reported embodies the results of some of these experiments.
The Pathogenicity of the Avian Tubercle Bacillus
Authors: L'Esperance Elise S.
Published: December 2022

Until recent years the avian tubercle bacillus has received very little attention from the host of investigators in the field of tuberculosis. The most plausible explanation for this neglect appears to be the generally accepted view that the avian tubercle bacillus is only slightly pathogenic for mammalia.

Koch, in 1890, raised the practical question as to whether the avian bacillus might be pathogenic for human beings and suggested continued study of this point through efforts to cultivate this organism from human disease.

Plum (Copenhagen, 1925), in a recent monograph on the incidence of avian tuberculosis in mammalia finds in a review of the literature and from personal observations, that the avian bacillus is pathogenic in varying degrees for man and other mammalian animals.

Isolated instance of spontaneous avian infection in man have been reported (Löwenstein, Pansini, Joannovic, Landouzy and others). The majority of these cases were characterized by a septicaemic type of disease.
The Relation of Serum Dilution and of Antigen Density to the Non-Specific Precipitations of Fowl Serum
Authors: Schilling S. J. , Schilling G. S.
Published: December 2022

In conducting the agglutination test on the blood of fowls to determine which birds are carriers of Salmonella pullorum, the etiologic agent of bacillary white diarrhea of chicks, a non-specific precipitation has been encountered by most, if not all, workers. This phenomenon, commonly called the cloudy reaction, frequently obscures and may in some instances inhibit the agglutination reaction.

A number of studies have appeared in which the investigators were concerned with finding the cause of this non-specific precipitation and with finding a means of avoiding it. It has been proposed to starve (1) the birds for a period before obtaining blood samples, and to add NaOH to a concentration of 0.04 per cent (2) or formalin to yield a concentration of 0.1 per cent in the agglutinating antigen (3). The means of avoiding the cloudy reaction by addition of NaOH although not uniformly effective, appears to be finding wide acceptance.
Quantitative Studies on the Action of Compound Hemolysins
Authors: Gahl Rudolf , David Norman , Kelleher Alice
Published: December 2022

New experimental material was presented in graphical form. The shape of the curves which are characteristic of the hemolytic reaction, their zones and the systems which they form were discussed in a qualitative way.

One of the zones was proven to be due to the presence of amboceptor in the complement. Regarding another zone the thesis was proposed that it is due to the presence of complement in the amboceptor which would imply that heat inactivation, at least as ordinarily conducted, does not destroy all the complement contained in the amboceptor before inactivation. A third zone was considered as representing the reaction between amboceptor and complement uncontaminated by side reactions. It was shown that this zone is utilized in the Wassermann test. It was also shown that the shape of the characteristics within this zone does not vary with the specimen of amboceptor and complement serum.

Cross-section curves show the typical S-shape observed by Manwaring. This shape was found to be due to the varying resistance of the individual corpuscles towards lysis.

The idea advanced in the second part of this paper that the shape of the characteristic curves depends only on amboceptor and complement serum but not on the concentration and character of the blood corpuscles was supported by experimental evidence.
Distribution of Antibodies in the Serum and Organs of Rabbits
Authors: Freund Jules
Published: December 2022

Previous work (1) has shown that agglutinins can be recovered from the organs of actively or passively immunized rabbits by extraction with salt solution, and that there is a definite quantitative relation between the antibody content of the serum and that of the organs. The purpose of the present work is to establish whether such a relation holds true for other antibodies.

In the literature on the subject there are several reports on the quantitative relation between the antibody content of the serum and organs of lower animals and man. (a) One group of studies were undertaken to establish the site of antibody-production. In these studies, most of the animals were examined very shortly after the injection of antigen, at a time when presumably the antibody-content of the site of antibody-production is relatively high, i.e., when the final distribution of the antibodies produced has not been reached.
Immunological Investigations in Tropical Sprue in Porto Rico
Authors: Weiss Charles , Costa Mandry O.
Published: December 2022

An investigation was made to determine whether the untoward gastro-intestinal reactions observed in sprue patients (diarrhoea, tympanites, flatulence, etc.) after eating certain types of food might be of the nature of specific hypersensitiveness. A careful survey was made of the foods commonly eaten by the people of Porto Rico and representative types were selected for cutaneous tests. These include proteins prepared from rice, beans, pork, cod-fish, cocoanut, etc., sugars (saccharose and fructose), fats and oils (lard, butter, etc.), starches prepared from rice potatoes, beans, etc., and local spices and coffee.

Our results were clearly negative and indicate that the untoward digestive symptoms of sprue patients are not due to any specific sensitization to any food products.
On the Presence of Heterophile (Forssman's) Antigen in Bacteria of the Paratyphoid-Dysentery Group
Authors: Jungeblut Claus W. , Ross Alexander T.
Published: December 2022

Immunization of rabbits with certain strains of B. dysenteriae Shiga or B. paratyphosus B was followed with great regularity by the appearance in the serum of hemolysins active for sheep and goat red corpuscles, but inactive for those of the human or rabbit. No formation of hemolysins was noted by immunizing guinea pigs with the same cultures. Hemolytic Shiga and paratyphoid B sera fixed complement specifically in the presence of true Forssman antigen. The heterophile antibodies in Shiga and paratyphoid B sera were completely and specifically absorbed by contact with their homologous bacterial antigens as well as by absorption with true Forssman antigen. Intravenous injection of Shiga and paratyphoid B sera into guinea pigs was only occasionally followed by a characteristic systemic reaction due to primary antiserum toxicity. Intracutaneous injection of Shiga and paratyphoid B sera into white guinea pigs and dogs induced frequently a well defined local, inflammatory reaction of the allergic type, particularly in the case of the latter sera. Complement fixation between true Forssman antisera and Shiga or paratyphoid B bacilli as the respective antigens was not readily demonstrable. The reactions were only faint and occurred irregularly. Absorption of true Forssman antisera by Shiga or paratyphoid B bacilli caused no definite loss of heterophile hemolysins in such sera. No evidence was found for the presence of heterophile antigen in strains of B. paradysenteriae (Flexner), B. paratyphosus A and B. enteritidis (Gaertner).
Antibody Studies in Serum Sickness
Authors: Tuft Louis , Ramsdell Susan Griffith
Published: December 2022

The general findings of Longcope and Rackemann, as to the presence of circulating antibodies following serum disease and their absence following treatment with antisera without serum disease, have been confirmed by this study. In addition, we have shown that antibody content is conditioned by the intensity of the disease and by the interval after the onset of the disease at which the bleeding is made; that anaphylactic antibody is more regularly present than has been previously indicated; that the positive Prausnitz-Küstner reaction may be demonstrated in a large proportion of cases; and that the passive sensitization of the guinea pig ear-skin could be regularly induced.

A definite relationship between the antibody responsible for the Prausnitz-Küstner reaction and the basic mechanism of serum disease is not clear; our results indicate no more than that this antibody occurs as one phase of a general stimulation of the various antibodies, initiated by a cellular reaction to the presence of a foreign serum; that it differs from an atopic reagin, in its experimental manifestations, only in that it persists in the serum of the patient but for a short time; and that the finding of this antibody in serum disease sera may be regarded as an instance of reagin production to a typical atopen in non-atopic individuals.
Cutting Edge: CD40 Engagement Up-Regulates Cyclooxygenase-2 Expression and Prostaglandin E2 Production in Human Lung Fibroblasts
Authors: Zhang Ying , Cao H. James , Graf Beth , Meekins Heather , Smith Terry J. , Phipps Richard P.
Published: December 2022

A newly emerging view of fibroblasts is that they are vital for initiating inflammation and respond to and direct the activities of leukocytes. Human fibroblasts can express CD40, an activation Ag the ligand of which is displayed by activated leukocytes. We demonstrate here that CD40 engagement on human lung fibroblasts dramatically increases proinflammatory PGE2 synthesis. This up-regulation is mediated through an induction of cyclooxygenase-2 (Cox-2) since Cox-2-selective inhibitors block the up-regulation. Western and Northern blot analyses demonstrated that Cox-2 protein and mRNA are dramatically increased in fibroblasts following CD40 engagement. We conclude that CD40 is a major pathway in human fibroblasts for the induction of Cox-2. There is intense interest in devising strategies for disruption of the CD40-CD40 ligand system to blunt inflammation. Such an intervention would be expected to attenuate the up-regulation of fibroblast Cox-2 and PGE2 production at the site of tissue injury.
Avoidance of Self-Reactivity Results in Skewed CTL Responses to Rare Components of Synthetic Immunogens
Authors: Purcell Anthony W. , Chen Weisan , Ede Nicholas J. , Gorman Jeffrey J. , Fecondo John V. , Jackson David C. , Zhao Yuming , McCluskey James
Published: December 2022

In studying the CTL recognition of peptide determinants derived from the nuclear Ag La (SS-B), we observed significant skewing of the response toward rare components present within the immunogen. Thus, priming of naive mouse lymphocytes in vitro with a synthetic H-2Kb-binding peptide comprising human La (hLa) residues 51–58 resulted in class I-restricted cytotoxic T cells that failed to recognize naturally presented hLa 51–58 peptide. Instead, the majority of T hybrids recognized a low abundance (≤1%) contaminant present at picomolar concentrations in the original synthesis and identified as a peptide adduct containing N,4-t-butyl asparagine at position 6 of the hLa 51–58 sequence. The preferred T cell recognition of the butyl adduct was not due to increased affinity of this peptide for the H-2Kb molecule or to the antagonism of CTL recognizing the unmodified determinant. Rather, the bias in the immune response appeared to be the result of partial self-tolerance to the homologous mouse La 51–58 determinant, which differs from its human counterpart by only a single amino acid at position 1 (T→I). Accordingly, the CTL response appeared to be focused on “non-self” ligands present within the synthesis, even though they were present at very low concentrations. These observations have significant implications for the use of synthetic peptide vaccines, especially those designed to manipulate responses to self peptides such as tumor Ags in which self-tolerance may result in unexpected reactivity.
A Fusion of the EBV Latent Membrane Protein-1 (LMP1) Transmembrane Domains to the CD40 Cytoplasmic Domain Is Similar to LMP1 in Constitutive Activation of Epidermal Growth Factor Receptor Expression, Nuclear Factor-κB, and Stress-Activated Protein Kinase
Authors: Hatzivassiliou Eudoxia , Miller William E. , Raab-Traub Nancy , Kieff Elliott , Mosialos George
Published: December 2022

The EBV latent infection transforming protein, LMP1, has six hydrophobic transmembrane domains that enable it to aggregate in the plasma membrane and a 200-amino acid carboxyl-terminal cytoplasmic domain (CT) that activates nuclear factor-κB and induces many of the phenotypic changes in B lymphocytes that accompany CD40 activation. Since the phenotypic effects of LMP1 are similar to those of activated CD40, we now compare signaling from the LMP1 CT with that from the CD40 CT fused to the LMP1 transmembrane domains. The LMPCD40 chimera was similar to LMP1 in nuclear factor-κB activation and in up-regulation of epidermal growth factor receptor expression. CD40 ligation was known to activate the stress-activated protein kinase, and both LMPCD40 and LMP1 are now shown to induce stress-activated protein kinase activity in the absence of ligand. Deletion of the first four transmembrane domains of LMP1 abrogated LMP1 aggregation in the plasma membrane and nearly abolished signaling from LMP1 or the LMPCD40 chimera. These results highlight the role of LMP1 as a constitutively active receptor similar to CD40 and provide a novel approach for the generation of ligand-independent receptors.
Autologous Human Monocyte-Derived Dendritic Cells Genetically Modified to Express Melanoma Antigens Elicit Primary Cytotoxic T Cell Responses In Vitro: Enhancement by Cotransfection of Genes Encoding the Th1-Biasing Cytokines IL-12 and IFN-α
Authors: Tüting Thomas , Wilson Cara C. , Martin Dina M. , Kasamon Yvette L. , Rowles Jennifer , Ma Debora I. , Slingluff Craig L. , Wagner Stephan N. , van der Bruggen Pierre , Baar Joseph , Lotze Michael T. , Storkus Walter J.
Published: December 2022

DNA-based immunization strategies designed to elicit cellular antitumor immunity offer an attractive alternative to protein- or peptide-based approaches. In the present study we have evaluated the feasibility of DNA vaccination for the induction of CTL reactivity to five different melanoma Ags in vitro. Cultured, monocyte-derived dendritic cells (DC) were transiently transfected with plasmid DNA encoding human MART-1/Melan-A, pMel-17/gp100, tyrosinase, MAGE-1, or MAGE-3 by particle bombardment and used to stimulate autologous PBMC responder T cells. CTL reactivity to these previously identified melanoma Ags was reproducibly generated after two or three stimulations with genetically modified DC. Co-ordinate transfection of two melanoma Ag cDNAs into DC promoted CTL responders capable of recognizing epitopes from both gene products. Coinsertion of genes encoding the Th1-biasing cytokines IL-12 or IFN-α consistently enhanced the magnitude of the resulting Ag-specific CTL reactivity. Importantly, DC transfected with a single melanoma Ag cDNA were capable of stimulating Ag-specific CTL reactivity restricted by multiple host MHC alleles, some of which had not been previously identified. These results support the inherent strengths of gene-based vaccine approaches that do not require prior knowledge of responder MHC haplotypes or of relevant MHC-restricted peptide epitopes. Given previous observations of in situ tumor HLA allele-loss variants, DC gene vaccine strategies may elicit a greater diversity of host therapeutic immunity, thereby enhancing the clinical utility and success of such approaches.
CD4+CD25+ T Cells Inhibit Both the Induction and Effector Function of Autoreactive T Cells and Represent a Unique Lineage of Immunoregulatory Cells
Authors: Suri-Payer Elisabeth , Amar Anna Z. , Thornton Angela M. , Shevach Ethan M.
Published: December 2022

Thymectomy of susceptible strains of mice on day 3 of life results in a spectrum of organ-specific autoimmunity that can be prevented by reconstitution of the thymectomized animals early in life with normal adult lymphocytes. The effectors and suppressors of autoimmunity in this model have been convincingly shown to be CD4+ T cells. It has been demonstrated recently that the regulatory CD4+ T cells that prevent disease coexpress CD25. We have further characterized the population of CD4+CD25+ immunoregulatory cells and demonstrated that they can suppress not only the induction of disease post-thymectomy, but can also efficiently suppress disease induced by cloned autoantigen-specific effector cells. Furthermore, the CD4+CD25+ T cells appear to be members of a unique lineage of regulatory T cells, as the induction of CD25 expression on a monospecific population of T cells derived from TCR transgenic SCID mice did not result in suppression of post-thymectomy autoimmunity. In addition, the TCR transgenic SCID mice were highly susceptible to autoimmune disease induced by the cloned line of autoantigen-specific effectors, while normal mice were relatively resistant. The capacity of the cloned line to transfer disease to nu/nu recipients could be inhibited by normal spleen cell populations containing CD4+CD25+ cells and by purified CD4+CD25+ cells. Although the target Ag(s) and mechanism of action of the CD4+CD25+ T cells remain to be determined, it is likely that they also play an important role in modulating other autoimmune diseases that are mediated by activation of “ignorant” self-reactive T cells present in the normal peripheral lymphocyte pool.