bluuebunny/crossref_metadata_2025_split huggingface dataset:
IL-12 is an effective adjuvant to recombinant vaccinia virus-based tumor vaccines: enhancement by simultaneous B7-1 expression.
Authors: Rao J B , Chamberlain R S , Bronte V , Carroll M W , Irvine K R , Moss B , Rosenberg S A , Restifo N P 
Published: December 2022

Abstract
A number of cytokines and costimulatory molecules involved in immune activation have recently been identified including IL-12, a heterodimeric cytokine that supports the development of cell-mediated immunity, and B7-1, a costimulatory molecule involved in the activation of T lymphocytes. We explored the use of these immunomodulants as molecularly defined adjuvants in the function of recombinant anticancer vaccines using a murine model adenocarcinoma, CT26, transduced with a model Ag, beta-galactosidase (beta-gal). Although IL-12 given alone to mice bearing tumors established for 3 days did not have consistent antitumor activity, a profound therapeutic effect was observed when IL-12 administration was combined with a recombinant vaccinia virus (rVV) encoding beta-gal called VJS6. On the basis of the reported synergistic effects of IL-12 and the costimulatory molecule B7-1 (CD80) in vitro, we immunized mice with a double recombinant vaccinia encoding both the model tumor Ag and the costimulatory molecule B7-1, designated B7-1 beta-gal rVV. The adjuvant administration of IL-12 after immunization with this virus significantly enhanced survival in tumor-bearing animals. T cell subset depletions demonstrated that the in vivo activity of IL-12 was largely independent of CD4+ T lymphocytes, whereas the in vivo activity of a B7-1 rVV required both CD4+ and CD8+ T cells to elicit maximal therapeutic effect. To our knowledge, this is the first description of B7-1 and IL-12 cooperation in vivo and represents a novel strategy to enhance the efficacy of recombinant anticancer vaccines.
Tyrosine-phosphorylated Cbl binds to Crk after T cell activation.
Authors: Sawasdikosol S , Chang J H , Pratt J C , Wolf G , Shoelson S E , Burakoff S J 
Published: December 2022

Abstract
Crk is a Src homology 2 (SH2)/Src homology 3 (SH3)-containing adapter protein that has been implicated in intracellular signaling in fibroblasts and PC12 pheochromocytoma cells. Crk has been shown to bind to a tyrosine-phosphorylated protein of 116 kDa after TCR-mediated T cell activation. Here we demonstrate that the Crk-associated p116 phosphoprotein is not the Crk-associated substrate (Cas) but, rather, is a protein product of the c-cbl proto-oncogene. Whereas Cas was not tyrosine-phosphorylated after T cell activation, Cbl became highly phosphorylated. Crk immunoprecipitates from activated T cell lysates contain tyrosine-phosphorylated Cbl. This association is mediated by the SH2 domain of Crk, as evidenced by the interaction between Cbl and the fusion protein product of a glutathione S-transferase (GST) expression construct encoding the Crk-SH2 domain in vitro. Furthermore, phosphopeptide-binding studies revealed that the GST-Crk SH2 domain binds to a tyrosine-phosphorylated peptide corresponding to amino acids 770-781 of Cbl with high affinity. Cbl is a protein tyrosine kinase (PTK) substrate that becomes phosphorylated after engagement of numerous cell surface receptors including the TCR. Data revealed by genetic studies in the nematode, Caenorhabditis elegans, implicates a Cbl-like molecule, Sli-1, as a negative regulator of the Let-23-signaling pathway. Because the signal from the Let-23 pathway affects the activation status of the Let-60 (Ras homologue in C. elegans) pathway, the activation-dependent association between Crk and Cbl may represent another TCR-generated signal leading to Ras-related pathways.
Systemic administration of cellular IL-10 induces an effective, specific, and long-lived immune response against established tumors in mice.
Authors: Berman R M , Suzuki T , Tahara H , Robbins P D , Narula S K , Lotze M T 
Published: December 2022

Abstract
Cellular IL-10 (cIL-10), the collective term for human and murine IL-10, has both stimulatory and inhibitory effects on diverse cell types, including costimulation of T cell proliferation, chemoattraction of CD8+ T cells, and stimulation of lymphokine-activated killer cell activity. Human IL-10 (hIL-10) differs from its EBV homolog viral IL-10 (vIL-10) by only 16% at the amino acid level; however, vIL-10 shares with cIL-10 predominantly inhibitory effects, such as macrophage deactivation. We administered cIL-10 systemically to mice bearing established (day 7) sarcomas, melanomas, or colorectal carcinomas. At high doses (20 to 60 micrograms/day x 7 days), cIL-10 induced rejection of tumors, delaying tumor outgrowth or resulting in complete cure. Sublethal irradiation (500 rad) of mice prior to tumor inoculation abrogated the IL-10 effect. Cured mice were immune to subsequent rechallenge with 10-fold higher inoculation with the same, but not a different, tumor. IL-12 also has potent antitumor activity and interacts with IL-10 in both complementary and antagonistic ways; co-administration of both cytokines resulted in additive antitumor activity. To compare cIL-10 vs vIL-10 effects in vivo, we engineered CL8-1 melanoma transfectants bearing the vIL-10 or the murine IL-10 (mIL-10) gene. Local secretion of mIL-10 induced rejection of tumors, while vIL-10 resulted in accelerated outgrowth. Subsequent systemic administration of cIL-10 to mice bearing vIL-10-transduced tumors completely reversed the local suppressive effects, leading to rejection, suggesting distinct pathways for cIL-10 and vIL-10 effects. That cIL-10 can stimulate the acquisition of an effective, specific, and long-lived antitumor immune response in murine models and can reverse the local immunosuppressive effects of vIL-10 indicates a potential role for cIL-10 administration in the biologic therapy of cancer and suggests a broader interpretation of IL-10 biology.
Prevention of experimental autoimmune myasthenia gravis by a monoclonal antibody to a complementary peptide for the main immunogenic region of the acetylcholine receptors.
Authors: Araga S , Galin F S , Kishimoto M , Adachi A , Blalock J B 
Published: December 2022

Abstract
We have previously reported that a complementary peptide (denoted RhCA 67-16), encoded by RNA complementary to that of the Torpedo acetylcholine receptor (AChR) main immunogenic region (MIR), AChR residues alpha 61-76, induces polyclonal and monoclonal Ab reactive with Ig against the AChR MIR. RhCA 67-16 vaccination also protected against the development of experimental autoimmune myasthenia gravis (EAMG) in Lewis rats. In the present report, we found that a mAb (denoted TCM 240, IgG1 kappa) against RhCA 67-16 recognized three different idiotypic Ab (mAb 6, mAb 35, and mAb 198), which were previously reported by others to recognize the AChR MIR and to cause EAMG. Based on these results, TCM 240 was tested for prophylactic effects in EAMG. EAMG induced passively by mAb 35 was inhibited by simultaneous injection with TCM 240. The disease severity was inversely paralleled by the ratio of mAb 35 to TCM 240. EAMG induced by immunization with purified native Torpedo AChR was also inhibited by TCM 240, but not a control mAb. The inhibitory effect of TCM 240 on actively induced EAMG occurred without significantly lowering the overall AChR Ab levels, which indicates a limited repertoire of disease-causing Ab in EAMG and perhaps MG. Such findings suggest the existence of an EAMG-associated Id and also support the concept of an MIR. In a more general sense, these results demonstrate that prophylactic and perhaps diagnostic mAb for autoimmune diseases can be produced by immunization with complementary peptides for disease-associated epitopes.
Antigen-receptor engagement in B cells induces nuclear expression of STAT5 and STAT6 proteins that bind and transactivate an IFN-gamma activation site.
Authors: Karras J G , Wang Z , Coniglio S J , Frank D A , Rothstein T L 
Published: December 2022

Abstract
The signal transducer and activator of transcription (STAT) family of transcription factors is triggered by cytokine and growth factor receptors in a number of cell types, and binds to a consensus sequence defined in part by the IFN-gamma activation site (GAS). It is not known whether these transcription factors respond to other kinds of growth stimuli, and, with particular relevance to lymphocytes, it is not known whether STAT proteins participate in Ag-specific responses. To determine the role of STAT proteins, coupling between Ag-receptor cross-linking and nuclear expression of DNA-binding protein complexes that recognize GAS sequences was evaluated. Ag-receptor triggering in primary B lymphocytes stimulated nuclear expression of a complex that specifically binds the IFN response factor-1 (IRF-1) GAS sequence, and is distinguished by electrophoretic mobility and GAS preference from IRF-1 GAS-binding complexes induced by IFN-gamma. Activation of nuclear IRF-1 GAS-binding activity by sIg was inhibited by the tyrosine kinase inhibitor, herbimycin A, and binding activity was eliminated by tyrosine phosphatase treatment. Activation of IRF-1 GAS-binding activity was blocked by depletion of protein kinase C. The IRF-1 GAS-binding activity induced by sIg engagement in B cells was transcriptionally active, and was found to consist of immunoreactive STAT5 and STAT6 proteins. This work demonstrates that the STAT signaling pathway previously associated with cytokine signaling is triggered in B lymphocytes through Ag-receptor engagement in a protein kinase C-dependent fashion. This heretofore described cytokine signaling pathway may play a role in bringing about Ag-specific proliferative and differentiative responses.
Mucosal immunity to HIV-1: systemic and vaginal antibody responses after intranasal immunization with the HIV-1 C4/V3 peptide T1SP10 MN(A).
Authors: Staats H F , Nichols W G , Palker T J 
Published: December 2022

Abstract
To optimize mucosal immune responses to the HIV-1 peptide vaccine candidate T1SP10 MN(A), we intranasally immunized BALB/c and C57BL/6 mice with C4/V3 HIV-1 peptide together with the mucosal adjuvant cholera toxin (CT). Four doses over a 4-wk period resulted in peak serum anti-peptide IgG titers of &gt; 1:160,000 in BALB/c mice and &gt; 1:520,000 in C57BL/6 mice, and significant levels (&gt;1:30,000) persisted in both strains of mice for longer than 6 mo. Furthermore, intranasal immunization with peptide and CT induced serum IgG reactivity to HIV-1 gp120 and HIV-1(MN) neutralizing responses. The primary anti-peptide IgG subclass was IgG1, suggesting a predominant Th2-type response. In addition to elevated serum anti-peptide A responses, intranasal immunization with T1SP10 MN(A) and CT induced both vaginal anti-peptide IgG and IgA responses, which persisted for 91 days in both strains of mice. Vaginal anti-HIV IgA was frequently associated with secretory component, suggesting transepithelial transport of IgA into vaginal secretions. Cervical lymph nodes contained the highest relative concentration of anti-T1SP10 MN(A) IgG-producing cells, while the spleen was the next major site of anti-T1SP10 MN(A) IgG-producing cells. Ag-specific proliferative responses were also detected in cervical lymph node and spleen cell populations after intranasal immunization with T1SP10 MN(A) and CT. In addition, intranasal immunization with T1SP10 MN(A) and CT was able to induce anti-HIV cell-mediated immunity in vivo as indicated by the induction of delayed-type hypersensitivity. Therefore, intranasal immunization with hybrid HIV peptides provides a noninvasive route of immunization that induces both long-lived systemic and mucosal Ab responses as well as cell-mediated immunity to HIV.
Fc receptor off-signal in the B cell involves apoptosis.
Authors: Ashman R F , Peckham D , Stunz L L 
Published: December 2022

Abstract
By linking surface Ig to the FcR Fc gamma RII on the mouse B lymphocyte surface, whole anti-Ig has been shown to block cell cycle entry and subsequent Ab production, a phenomenon called the "Fc receptor off-signal." IL-4 or blocking Ab to Fc gamma RII, present with whole anti-Ig, restores cell cycle progress to the levels observed with F(ab')2 anti-Ig. The current study demonstrates that under "off-signal" conditions with whole anti-Ig, the early entry of B cells into apoptosis was accelerated relative to medium alone or equimolar F(ab')2 anti-Ig. All reagents tested which opposed the whole-anti-Ig-induced blockade of B cell cycle entry also protected B cells from apoptosis (IL-4, PMA, dextran sulfate, and the monoclonal anti-Fc gamma RII 2.4G2). This protective effect was most evident at 4 to 12 h, waning at later times. Low dose cycloheximide partially protected B cells from whole anti-Ig-induced apoptosis, but acted as a survival factor, failing to advance B cells from G0 phase or stimulate thymidine incorporation. Additive early apoptosis-associated membrane changes were transiently seen when whole anti-Ig was combined with other apoptosis-accelerating agents (trifluoperazine, staurosporine, dexamethasone, ionomycin, high-dose cycloheximide), but hypodiploid nuclei did not show this effect. B cells from bcl-2 transgenic mice showed less apoptosis when cultured with whole anti-Ig, or with any of the other agents tested. At 4 h the bcl-2-associated reduction in hypodiploid nuclei was greater than the reduction in membrane unpacking, but by 16 h this difference was much less. These results suggest that acceleration of apoptosis contributes to the inhibition of proliferation induced by whole anti-Ig.
Tenidap and other anion transport inhibitors disrupt cytolytic T lymphocyte-mediated IL-1 beta post-translational processing.
Authors: Perregaux D G , Svensson L , Gabel C A 
Published: December 2022

Abstract
LPS-activated murine peritoneal macrophages produce IL-1 beta but externalize little mature cytokine in the absence of a secondary stimulus, and CTLs previously were reported to serve this capacity. The release of 17-kDa IL-1 beta from LPS-activated BALB/c macrophages occurred rapidly after the addition of C57/B1-derived allogeneic CTLs; within 30 min of coculture, mature IL-1 beta was observed in the medium, and maximum release was achieved within 4 h. CTL-induced post-translational processing was efficient, and &gt;80% of newly synthesized pro-IL-1 beta was released into the medium as the 17-kDa species. Externalization of IL-1 beta required active recognition of the macrophage target by the CTL preparation; C57/B1 CTLs promoted the release of mature IL-1 beta from allogeneic BALB/c macrophages, but not from syngeneic C57/B1 macrophages. In contrast, extracellular ATP promoted mature IL-1 beta release from both macrophage populations. CTL-induced cytokine post-translational processing was blocked by anion transport inhibitors, including 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid, UK5099, and the anti-inflammatory agent tenidap. An analogue of tenidap, CP-100,829, was more effective as an inhibitor of both IL-1 beta post-translational processing and anion transport. In contrast, the close structural analogue CP-236,492 inhibited neither process. Tenidap's activity was reversible and was not mimicked by cyclooxygenase inhibitors or by cycloheximide. Therefore, tenidap disrupted CTL-induced IL-1 beta post-translational processing by a mechanism dependent on anion transport inhibition. Multiple stimuli are likely to operate in vivo to promote IL-1 beta post-translational processing, and anion transport inhibitors such as tenidap that suppress cytokine processing independently of the initiating stimulus thus represent attractive candidates as therapeutic regulators of IL-1 production.
Impaired signaling in alloantigen-specific CD8+ T cells tolerized in vivo: employing a model of Ld-specific TCR transgenic mice transplanted with allogenic hearts under the cover of a short-term rapamycin treatment.
Authors: Chen H , Luo H , Xu D , Loh D Y , Daloze P M , Veillette A , Qi S , Wu J 
Published: December 2022

Abstract
Peripheral tolerance of T cells is necessary because thymic deletion is not complete, and tissue-specific Ags exist outside the thymus. We have reported that persistent Ag is required to maintain peripheral tolerance in vivo. We suspect that the TCR signaling pathway in in vivo tolerized cells is compromised due to continuous exposure to the Ags. In this study, the TCR signaling events in these cells were investigated using TCR transgenic mice (2C mice) whose T cells are predominantly Ld alloantigen-specific CD8 cells. The 2C mice were thymectomized and then rendered tolerant to Ld Ag by allogenic heart transplantation plus short-term treatment with rapamycin. We found that 1) the in vivo tolerized CD8 cells have compromised intracellular Ca2+ flux upon mitogen stimulation; and 2) their cellular tyrosine proteins fail to be phosphorylated properly upon TCR cross-linking. These results indicate that the signaling pathway in the in vivo tolerized CD8 cells is indeed defective. We also found that 1) the tolerized CD8 cells have no characteristic surface markers; and 2) the allograft is probably the place where the rejection response is initiated according to the appearance of an early activation marker of T cells on graft-infiltrating cells.
Brain-derived gangliosides regulate the cytokine production and proliferation of activated T cells.
Authors: Irani D N , Lin K I , Griffin D E 
Published: December 2022

Abstract
Gangliosides may regulate the activity of the immune system in vivo, particularly within tissues such as neoplasms or the central nervous system, where they are most abundant. However, the specific mechanisms by which gangliosides modulate immune function remain incompletely understood. We have characterized the effects that brain-derived gangliosides have on specific steps of the T cell activation process in vitro. Gangliosides inhibit T cell proliferation downstream from the early activation events that are bypassed pharmacologically using the combination of a phorbol ester plus a calcium ionophore. These lipids block IL-2 and IFN-gamma gene transcription without inhibiting the production of IL-4 and IL-10 mRNA. This may be accounted for by the ability of gangliosides to prevent the activation of NF-kappaB in mitogen-stimulated T cells. Despite inhibiting IL-2 production, the antiproliferative effects of gangliosides are not reversed by adding supplemental IL-2 to the culture media. This defect persists because gangliosides also block the entry of activated T cells into the cell cycle. In this setting, phosphorylation of the retinoblastoma gene product, a protein whose phosphorylation state is an important regulator of normal cell cycle progression, is prevented. These studies help to define how gangliosides modulate T cell effector function in vitro. They also highlight the fact that certain T cell responses, namely the production of Th2-associated cytokines, are not inhibited by their actions.
Deletion in HCDR3 rescues T15 antibody mutants from a secretion defect caused by mutations in HCDR2.
Authors: Martin T M , Kowalczyk C , Stevens S , Wiens G D , Stenzel-Poore M P , Rittenberg M B 
Published: December 2022

Abstract
We recently described mutants of the murine anti-phosphocholine Ab T15, with changes in heavy chain complementarity determining region 2 (HCDR2) that caused loss of secretion. Surprisingly, the T15 HCDR2 mutations did not alter secretion when placed into the related anti-phosphocholine Ab D16, which differs from T15 only in HCDR3 and light (L) chain. Here, we exploit the differences between these two Abs to assess the basis of the secretion defect. The T15 L chain is not secreted in the absence of heavy (H) chain. In contrast, D16 L chain is secreted in the absence of H chain, as are most L chains. We co-expressed the T15 wild-type (wt) and mutant H chains with the D16 L chain, as well as with another secreted L chain, J558L. The mutant H chains were not secreted when expressed with either heterologous L chain. These results establish that the T15 L chain is not uniquely associated with the defect. The T15 and D16 Abs also differ in HCDR3 length in that D16 lacks four amino acid residues (Ser99, Ser100, Tyr100a, Trp100b) present in T15. We deleted these four residues from T15 wt and mutant H chains. Secretion of T15 wt was unaffected by the deletion, but shortening HCDR3 restored secretion in the HCDR2 mutants regardless of L chain association. Together these data demonstrate that both the HCDR2 and HCDR3 domains contain structural information that may affect the secretion competence of Abs.
CD19 regulates B lymphocyte signaling thresholds critical for the development of B-1 lineage cells and autoimmunity.
Authors: Sato S , Ono N , Steeber D A , Pisetsky D S , Tedder T F 
Published: December 2022

Abstract
CD19 serves as a cell surface response regulator that establishes signaling thresholds critical for B lymphocyte development and activation. B lymphocytes from CD19-deficient mice are hyporesponsive to transmembrane signals, while B lymphocytes from mice that overexpress CD19 to even a small extent (25% increase) become hyperresponsive. The B-1 subpopulation of B lymphocytes is particularly sensitive to CD19 regulation, since their development is severely decreased in CD19-deficient mice. The effect of altered CD19 expression levels on the development of B cells was therefore examined using transgenic mice that express varying levels of cell surface CD19. In this study, immature B cells within the bone marrow of wild-type mice were found to specifically up-regulate CD19 expression levels by twofold as they mature, while CD5+ B cells within the spleen and peritoneum expressed even higher levels of CD19. The development of CD5+ B cells was severely decreased in CD19-deficient mice, while there was a linear correlation between increased CD19 expression levels and the increased frequency of CD5+ B cells within the peritoneum and spleen. In fact, CD5+ B cells became a major B lymphocyte population in mice that overexpressed CD19. Increased expression of CD19 also correlated with increased levels of endogenous anti-DNA Abs and rheumatoid factor. These results indicate that up-regulated expression of CD19 is functionally important for B cell development and that CD19 establishes signaling thresholds that regulate the generation of B-1 lymphocytes as well as the development of autoantibodies.
Somatic hypermutation of a lambda 2 transgene under the control of the lambda enhancer or the heavy chain intron enhancer.
Authors: Klotz E L , Storb U 
Published: December 2022

Abstract
Previous experiments have suggested an important role for the Ig enhancers and transcription in targeting somatic hypermutation. To determine whether the requirement of the enhancers is Ig chain specific, we analyzed two lambda 2 light chain transgenes under the control of different enhancers, either the lambda 2-4 enhancer or the heavy chain intron enhancer. The transgenes were amplified and cloned from B220+PNAhigh B cells from either Peyer's patches (PP) or SRBC-immunized spleen. The lambda 2 transgene under the control of the lambda 2-4 enhancer underwent mutation in both the PP and splenic B cell populations, but at a frequency lower than endogenous light chain genes. This requirement for the lambda 2-4 enhancer could be replaced by the heavy chain intron enhancer. Interestingly, the heavy chain intron enhancer-driven lambda 2 construct showed evidence of statistically significant mutation in the PP B cell population, but not the spleen-derived population. This difference in somatic hypermutation suggests that a lower mutation frequency can be more readily detected in B220+PNAhigh B cells isolated from the PP. The ability of the heavy chain intron enhancer to replace the lambda 2-4 enhancer shows that the requirement for the Ig enhancers in somatic hypermutation is not Ig locus specific. Given that these Ig enhancers have very few elements in common, our results further suggest that the Ig enhancers are primarily important in the timing of transcription in the mutating B cell population.