bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unique processes of antibody assembly and systemic regulation enhance affinity maturation in salmonids (90.15)
Authors: Bromage Erin , Ye Jianmin , Kaattari Stephen 
Published: January 2023

Abstract
The salmonid humoral immune response is mediated primarily by the induction of a single antibody isotype, an 800 kDa tetrameric molecule. However, this antibody molecule possesses considerable structural diversity due to non-uniform disulfide cross-linking of its monomeric subunits. The potential association of antibody affinity with the degree of inter-monomeric disulfide bonding was examined. Three distinctly different routes were taken to examine this relationship; 1) fractionation and analysis of high and low affinity antibodies from individual immune sera by differential immunoadsorption, 2) selective induction of high vs. mixed affinity antibodies in vitro from the same population of cells, and 3) analysis of total serum antibodies undergoing affinity maturation in vivo. All three methods demonstrated a direct relationship between affinity and the degree of disulfide polymerization, with the most cross-linked forms possessing the highest affinity. Utilizing the transfer of labeled immunopurified antibody to naive hosts we have discovered that the persistence of these structural isomers in vivo is also regulated, with the preferential removal of the more reduced forms from circulation. Thus it appears that control of intramolecular disulfide polymerization of the antibody molecule combined with the selective removal of lower affinity antibodies from the circulation, is critical to achieve a mature antibody response in salmonid species.
CM1 ligation induces apoptosis via Fas/FasL interaction in ovarian cancer Caov-3 cells (92.11)
Authors: Hur Dae-Young , Park Ga-Bin , Hur Indo , Kim Hyunjin , Kim Yeong-Seok , Song Hyunkeun , Lee Hyun-Kyung , Kim Yoon Berm , Lee Wang Jae 
Published: January 2023

Abstract
In the previous study, we found that EBV-transformed B cells expressed CM1 (centrocyte/-blast marker 1), which was known as another possible marker of GC B cell and induced apoptosis of GC B cells. In the present study, we found that ovarian cancer cell line (Caov-3 cells) expressed CM1. And CM1 stimulus induced apoptosis in Caov-3 cells. So, we designed to elucidate the requirement of a death receptor, its’ role in subsequent activation of caspase-8 and the role of mitochondria in the induction of apoptosis. CM1 ligation with anti-CM1 mAb induced FasL expression in Caov-3 cells. Furthermore, anti-Fas blocking antibody, ZB4, blocked CM1-mediated apoptosis effectively in Caov-3 cells. Increased mitochondrial membrane permeabilization, which was measured by DiOC6, was observed. Caspase-8 inhibitor, z-IETD effectively blocked CM1-induced cell death. RT-PCR analysis showed up-regulated expression of Bax and Bad and down-regulated expression of Bcl-2. Western blot analysis showed down-regulated expression of procaspase-8 and PARP. The release of cytochrome c and translocation to nucleus of endoG and AIF were showed by confocal micoscopy. Based on these findings, we concluded that CM1 induced apoptosis could be mediated by Fas/FasL interaction in Caov-3 cells and CM1 might act as an effective apoptosis inducer in ovarian cancer cells.
Characterization of peptide binding by heat shock proteins upon antigen induction and under cellular stress (93.4)
Authors: Kelly John B , Binder Robert J , Srivastava Pramod K 
Published: January 2023

Abstract
Purified preparations of selected heat shock proteins (of the hsp90 and hsp70 families) are actually non-covalent complexes of HSPs with peptides that contain the MHC Class I-binding octa/nonamers. Several purified HSP-peptide complexes have been shown to specifically activate the immune system through delivery of the antigenic peptides to antigen-presenting cells (APC) for cross-presentation, but little is known about the formation of intracellular HSP-peptide complexes. The aim of this study is to quantify the relationship between MHC I-binding peptides (and their extended precursors) and chaperone proteins under two immunologically important states: induction of a neoantigen and cellular stress. We present here the development of a novel cell line, PIK23, which employs the modified version of ovalbumin, KOVAK, under the control of a synthetic, inducible promoter system. Using this cell line, we have identified MHC-I binding peptides associated with gp96 and Hsp70, and have begun to quantify these peptides in relation to the translation of the antigenic protein and state of cellular stress.
Monoclonal antibodies to HLA class I restricted influenza epitopes (93.8)
Authors: Gonzalez Melva L. , Wahl Angela R. , Hildebrand William H. 
Published: January 2023

Abstract
The immune response to viruses involves the presentation of peptide epitopes in the context of the human leukocyte antigen (HLA) class I molecule. The HLA class I molecule consists of a heavy chain, a light chain, and a peptide of 9–10 amino acids that is positioned in a groove formed by the class I heavy chain. Identification of HLA class I-restricted peptide epitopes that distinguish a virus-infected cell from a non-infected cell is positioned to facilitate studies of antigen presentation, viral diagnostics, and the design of viral vaccines/therapeutics. Recently, we have directly discovered epitopes presented by the class I HLA of influenza-infected cells. Using HLA tetramers and single chain trimers (SCT) as immunogens, we have produced monoclonal antibodies (mAb) to HLA class I molecules carrying viral peptide epitopes. The peptide/HLA specificity of the mAbs was confirmed by ELISA and by flow cytometry. The results of these experiments demonstrate that mAb specific for HLA/influenza peptide epitopes could be useful for studying the dynamics of viral epitope presentation and may represent a tool for targeting viral infected cells.
The role for DNA methylation in differentially regulating IL-7 receptor alpha expression by human T cells (94.22)
Authors: Kang Insoo , Hwang Kyung-A , Kim Ki-Chan , Kim Hang-Rae 
Published: January 2023

Abstract
IL-7 is critical for the development and survival of T cells. Recently, we found two subsets of human CD8+ T cells expressing IL-7Rahigh and IL-7Ralow with different cell survival responses to IL-7. Although these CD8+ T cell subsets have differential IL-7Ra gene expression, the mechanism for this is unknown. DNA methylation is an important gene regulatory mechanism and associated with inactivation of gene expression. Thus, we investigated the role for DNA methylation in differentially regulating IL-7Ra gene expression in human CD8+ T cells and Jurkat T cells. IL-7Rahigh CD8+ T cells had decreased methylation in the IL-7Ra gene promoter compared to IL-7Ralow CD8+ T cells and Jurkat T cells with low levels of IL-7Ra. Treating Jurkat T cells with 5-aza-2¡-deoxycytidine (5-aza-dC), which reduced DNA methylation, increased IL-7Ra expression. Plus, the unmethylated IL-7Ra gene promoter construct had higher levels of promoter activity than the methylated one as measured by a luciferase reporter assay. These findings suggest that a novel mechanism is involved in differentially regulating IL-7Ra expression in T cells through altering DNA methylation of the IL-7Ra gene promoter, and that methylation of this gene promoter could be a potential target for modifying IL-7-mediated T cell development and survival.
Dissecting the role of miRNAs in Natural Killer (NK) cells (94.27)
Authors: Savan Ram , Owens Garrison , Munroe David J , Young Howard A 
Published: January 2023

Abstract
Natural Killer cells play a vital role in the control of cancer and microbial infections. One of the mechanisms by which these cells act is through the production of interferon (IFN)-gamma in response to many extracellular signals. These extracellular signals have effects on transcriptional and post transcriptional regulation of IFN-gamma gene expression. MicroRNAs may be one of the important agents involved in post-transcriptional regulation of IFN-gamma gene expression. Furthermore, through bioinformatic analysis, putative miRNAs that might target IFN-gamma gene for gene regulation have been identified. Using miRNA arrays, we have screened for the expression of miRNAs in NK-92 cells stimulated for 4h with IL (interleukin) -2, IL-12, IL-15, IL-18, IL-21, IFN-alpha, PMA and a combination of IL-12 and PMA. Our studies by miRNA profiling indicate that miR29a, miR27 and miR181, through bioinformatics are known to target IFN-gamma, are modulated by signals that up-regulate IFN-gamma mRNA. This data forms a base-line to further study the role of microRNAs in NK cell biology. These studies will utilize lentiviruses to overexpress specific microRNAs or disrupt the miRNA pathway in order to elucidate the role of miRNAs in NK cell gene expression.
Temporal regulation of Stat5 activity determines cell differentiation program (94.3)
Authors: Fujii Hodaka , Hoshino Akemi 
Published: January 2023

Abstract
Erythropoietin (Epo) plays essential roles in erythropoiesis including expression of globin genes. It has been shown that Stat5 activation is important for Epo-induced globin gene expression. Although Stat5 is activated by various cytokines including interleukin (IL)-3 and IL-2, only Epo and a small number of cytokines induce erythroid differentiation and globin gene expression. It is not well understood how cytokine-specific gene expression is ensured. Here, by using a reporter gene system to monitor transcriptional activity of Stat5, we showed that sustained activation of Stat5 induces globin gene expression. We also showed that Epo but not IL-3 supports sustained activation of Stat5. These results underscore the importance of temporal regulation of Stat activity in the regulation of cytokine-specific gene expression and cell differentiation. IL-3 or IL-2 stimulation actively inhibits Epo-induced globin gene expression. The acidic region (the A-region) of the IL-2 receptor β chain was essential for this inhibition, suggesting a role of the A-region-coupled signaling molecules in inhibition of globin gene expression. The present study may provide insight into the regulatory mechanism of cytokine-specific gene expression.
This work is supported by NIH grant R01 AI059315 to H.F.
PLIC-1 is an inhibitor of TLR signaling (94.7)
Authors: Wang Tianyi , Biswas Nabanita 
Published: January 2023

Abstract
Toll-like receptors (TLRs) are key innate immune receptors that recognize non-self pathogens and hence trigger host responses. We have recently identified an ubiquitin-like protein named protein linking integrin associated protein to cytoskeleton 1 (PLIC-1) that interacts with the cytoplasmic domain of TLR4. The interaction between TLR4 and PLIC-1 was verified by co-immunoprecipitation. Further studies suggest that PLIC-1 may be interacting with multiple TIR domain containing proteins. PLIC-1 decreased the production of TRIF in an overexpression system. Consequently, PLIC-1 was found to inhibit the TRIF-mediated activation of both NF-kB and IFN-b pathways in macrophages. Lastly, reduction of endogenous PLIC-1 by shRNAi delivered via retroviral infection enhanced the cellular responses to LPS or poly I:C. Together, our results have implicated PLIC-1 as a negative regulator of TLR pathway.
This work is supported by the University of Pittsburgh faculty start-up fund.
Distinct Effects of IL-12 and IFN-a/b on CD8 T cell Effector Functions (95.18)
Authors: Ramos Hilario Jose , Farrar J. David 
Published: January 2023

Abstract
During viral infections, CD8 T cells act to promote immunity by eliminating virally infected cells. To accomplish this they employ immediate effector functions and promote the generation of memory populations with the capacity to respond to secondary challenge. The innate cytokines IL-12 and type I interferon (IFNa/b) have been shown to participate in both the effector and memory CD8 T cell response. However, the independent and direct pathways they activate have not been well characterized. We have recently examined the direct and independent roles of these cytokines on naïve human CD45RA+ CD27+CD8+ T cells developing in vitro. In these studies, we observed that IL-12 but not IFNa/b promote the generation of CD8 T cells capable of secreting IFN-g upon secondary challenge. Further, this correlates to enhanced CXCR3 expression, a chemokine receptor which homes cells to the site of primary infection. In contrast IFNa/b enhanced the expression of CCR7 which plays an important role in the trafficking of cells to the secondary lymphoid organs. Both IL-12 and IFNa/b augmented the expression of the cytolytic factors perforin and granzyme, however, polarization with both IL-12 and IFNa/b promoted enhanced cytolytic killing than polarization by either cytokine alone. Taken together, these results demonstrate that IL-12 and IFNa/b participate in both overlapping as well as unique pathways in human CD8 T cell development which may function to promote diverse immune responses dependent on the pathogen or cytokine milieu encountered during infection.
Adsorbed Fibrinogen Elicits Cytokine Production by Dendritic Cells (95.27)
Authors: Thacker Robert I. , Retzinger Gregory S. 
Published: January 2023

Abstract
Fibrinogen (fgn) readily coats surfaces, and has been implicated in inflammation, but its role is still ill-defined. Available evidence suggests it is adsorbed fgn that operates during inflammation. To better elucidate the role of adsorbed fgn, the protein was first bound to the surface of microscopic polymeric beads and then placed in the presence of human dendritic cells (hDC’s). Immature DC (iDC’s) produce more IL-6, IL-8 and MIP-1β and mature DC’s (mDC’s) produce more IL-6, MCP-1 and MIP-1β in response to adsorbed fgn than they do in response to solution phase fgn. IL-6 and MIP-1β production by iDC’s are reduced by anti-TLR4, anti-CD18 and anti-CD11c antibodies. IL-8 production by iDC’s is reduced by antibodies against CD11b, CD18 and TLR4. Only anti-TLR4 antibodies reduce IL-6 and MIP-1β production by mDC’s, while MCP-1 production is reduced by antibodies against CD18, CD11c and TLR4. The increased production of these inflammatory mediators by hDC’s in response to adsorbed fgn might enhance immune cell recruitment, thereby potentiating inflammation. These data also suggest that certain fgn receptors play a role in fgn-elicited production of IL-6, IL-8, MCP-1 and MIP-1β by hDC’s.
Altered T lymphocyte response to respiratory syncytial virus in CCR6−/− mice (96.3)
Authors: Kelley Lara , Schaller Matthew , Lukacs Nicholas 
Published: January 2023

Abstract
The CC chemokine receptor 6 is unique in the chemokine family because it binds to only a single ligand, CCL20. CCL20 is expressed in epithelial cells in tissues such as skin, gut mucosa and lungs. Studies using CCR6 deficient mice revealed a defect in dendritic cell positioning in the gut mucosa, suggesting a role for CCL20-CCR6 in leukocyte homeostasis and proper positioning of these cells in mucosal tissues. In a mouse model of asthma, CCR6−/− mice showed reduced airway hyperreactivity and less mucus production. The potential pathological role for CCL20-CCR6 led us to investigate this receptor-ligand pair in a mouse model of viral infection caused by respiratory syncytial virus (RSV), a negative strand RNA virus that can cause severe complications in infants, the elderly and immunocompromised individuals. We found that CCR6−/− mice had lower numbers of activated CD4 and CD8 T cells in the lungs at days 6 and 9 post-RSV infection, as well as reduced Th1 and Th2 cytokines in both lungs and lymph nodes. Interestingly, we also found that these mice had more efficiently cleared virus by day 6 post-infection. This suggests the involvement of a cell type other than T lymphocytes that in the absence of CCR6 is able to impart viral immunity.
This research is supported by NIH grant AI36302
Integrin alpha-1 deficiency does not affect resistance to pulmonary Mycobacterium tuberculosis infection in mice but leads to necrosis within granulomatous lesions (97.12)
Authors: Taylor Jennifer Lynn , Bielefeldt-Ohmann Helle , Pozzi Ambra , Izzo Angelo 
Published: January 2023

Abstract
The hallmark of Mycobacterium tuberculosis infection is the granuloma, a highly dynamic immune structure that ‘walls off’ the bacilli during chronic infection. Here, we examined if α1β1 integrin is required in the development and maintenance of the granulomatous structure during infection using an α1-integrin knockout mouse (α1-null). The α1β1 integrin is expressed on activated macrophages and T cells, and interacts with collagen molecules in the extracellular matrix (ECM). To determine if the α1-integrin molecule is necessary for trafficking of activated T cell within the lungs, cells from the lungs of infected α1-null mice were stained for CD4, CD44 and CD62L. The numbers of activated and IFNγ-producing CD4-positive T cells were increased in the α1-null strain during chronic infection. While there were no differences in bacterial load between the α1-null and wild type mice, histology revealed striking differences in granuloma formation and structure. MMP-9 and TNFα were decreased in the α1-null mice and alveolar septae were distinct and markedly thickened. By day 180, there were regions of necrosis within the granulomas, characterized by cellular and nuclear debris. These results reveal that while the α1β1 integrin is not a factor required for resistance to M. tuberculosis, it does play a role in granuloma formation and integrity of the structure.
Funding: NIH AI52040 and Colorado State University CRC
CRUCIAL ROLE OF CD44 IN LIVER INFLAMMATION (97.6)
Authors: kimura kiminori , nagaki Masahito , Kakimi Kazuhiro , Nakayama Toshinori , Taniguchi Masaru , Moriwaki Hisataka 
Published: January 2023

Abstract
CD44 on inflammatory cells is well known as an adhesion molecule and blocking CD44 is thought to be one of the therapeutic strategies for inflammatory diseases. Here, we showed that CD44 knock-out (KO) mice exhibit suppressed liver inflammation during the early phase after carbon tetrachloride (CCL4) injection due to reduced infiltration of inflammatory cells and reduced cytokine production. In contrast, these mice showed severe liver inflammation with increased numbers of apoptotic hepatocytes at the late phase. This induction of hepatocyte apoptosis was triggered by reduced NF-kB activity, which was induced by low concentrations of inflammatory cytokines in the liver. Through this inflammatory response, the kinetics of NKT cells were distinctive, with increased infiltration into the liver by greater proliferation and migration, which was independent of the CD44 pathway. Furthermore, MIP-2 derived from NKT cells contributed to exacerbation of liver injury, since neutralization of MIP-2 significantly protected against hepatocyte apoptosis in CD44KO mice. These findings suggest that blocking of CD44 as a therapeutic approach for inflammatory liver diseases might be specific for particular immune systems in the liver.
The Role of LFA-1 in T cell Trafficking and Functions in Demyelinating Disease (99.5)
Authors: Dugger Kari J , Zinn Kurt R , Bullard Daniel C , Barnum Scott R 
Published: January 2023

Abstract
Multiple sclerosis (MS) is characterized by autoimmune damage to central nervous system (CNS) myelin, resulting in impaired nerve function. Integrins such as lymphocyte function-associated antigen-1 (LFA-1) are thought to be important in leukocyte trafficking to the CNS and disease development. Studies using monoclonal antibodies to LFA-1 in experimental autoimmune encephalomyelitis (EAE), the animal model for MS, have provided conflicting results regarding the role of LFA-1 in EAE. To overcome the limitations of the antibody-based approach, we used LFA-1-deficient mice and a transgenic mouse (T-lux) with a hCD2 promoter that drives expression of the luciferase gene specifically in T cells thereby providing a novel method of a real-time depiction of T cell trafficking patterns. We found that both LFA-1-deficient and LFA-1 hemizygous mice do not develop clinically significant EAE and have markedly reduced leukocyte infiltration into the CNS. Encephalogenic LFA-1-deficient T-lux cells adoptively transferred into wild type recipients do not localize to the CNS, whereas MOG-specific wildtype T-lux cells transferred to wildtype or LFA-1-deficient recipients, readily migrate to the CNS and draining lymph nodes and proliferate. These data demonstrate that LFA-1 on T cells is necessary for myelin-specific T cells to enter into the CNS and initiate disease.
Supported by NIH grant NS46032.
Developmental Control of Integrin Expression Regulates T Helper-2 Effector Homing (99.6)
Authors: Lee Seung-Hyo , Kheradmand Farrah , Corry David 
Published: January 2023

Abstract
Integrin CD18, a component of the lymphocyte function-associated antigen-1 (LFA-1) complex that also includes CD11a, is essential for Th2, but not Th1, cell homing, but the explanation for this phenomenon remains obscure. Here, we investigate the mechanism by which Th2 effector responses require the LFA-1 complex. CD11a-deficient T cells showed normal in vitro differentiation and function. However, Th2 cell-dependent allergic lung disease was markedly reduced in CD11a null mice and wild type mice given LFA-1 inhibitors, whereas control of infection with Leishmania major, a Th1-dependent response, was enhanced. In both disease models, recruitment of IL-4−, but not IFN-g, secreting cells to relevant organs was impaired, as was adhesion of Th2 cells in vitro. These diverse findings were explained by the markedly reduced expression of CD29, an alternate homing integrin, on Th2, but not Th1, cells, which precludes Th2 homing in the absence of CD11a. Thus, murine Th1 and Th2 cells utilize distinct integrins for homing, suggesting novel opportunities for integrin-based therapeutic intervention in diverse human ailments.
CXCR6 promotes atherosclerosis by supporting T cell homing, interferon gamma production and macrophage accumulation in the aortic wall (99.8)
Authors: Galkina Elena , Harry Brian , Ley Klaus 
Published: January 2023

Abstract
T cells are important in atherosclerosis, but very little is known about the mechanisms behind lymphocyte recruitment into atherosclerosis-prone aortas. We tested the hypothesis that CXCR6, a chemokine receptor that is expressed on a subset of T cells and natural killer T cells, is involved in lymphocyte homing into the aortas and modulates atherosclerosis. To investigate the role of CXCR6 in atherosclerosis, we bred CXCR6-deficient (CXCR6GFP/GFP) mice with apolipoprotein E-deficient (ApoE−/−) mice. CXCR6GFP/GFP/ApoE−/− mice fed a western diet for 17 weeks or a chow diet for 56 weeks had decreased atherosclerosis compared with ApoE−/−controls. Flow cytometry analysis of the aortas from CXCR6GFP/GFP/ApoE−/− mice showed that the reduction of atherosclerosis was accompanied by a decreased percentage of CXCR6+ T cells within the aortas. Short–term homing experiments demonstrated that CXCR6 is involved in the recruitment of CXCR6+ leukocytes into the atherosclerosis-prone aortic wall. The reduced percentage of CXCR6+ T cells within the aortas was associated with diminished production of IFNγ and reduced accumulation of CD11b+/CD68+ macrophages in the aortas. These data provide evidence for a functional role of CXCR6 in atherosclerosis by altering of the recruitment of CXCR6+ leukocytes and modulating of the local immune response within the aorta.
This work is supported by NHI HL 58108, 55798 and AHA 0525532U.