bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of platelet-activating factor in protecting against lipopolysaccharide-induced endotoxic shock (33.3)
Authors: Jeong Young-Il , Jung In Duk , Lee Jun Sik , Lee Chang-Min , Chun Sung Hak , Jeong Soo kyung , Shin Yong Kyoo , Park Yeong-Min 
Published: January 2023

Abstract
AbstractPlatelet-activating factor (PAF) has been long believed to be associated with many pathophysiological processes during septic shock. Here we present novel activities for PAF in the LPS-mediated endotoxic shock. In vivo PAF treatment immediately after LPS challenge markedly improved the survival rate against mortality from endotoxic shock. In addition, this treatment prominently attenuated LPS-induced profound hypotension, excessive polymorphonuclear neutrophil infiltration, severe multiple organ failure, and lymphocyte apoptosis. These protective effects of PAF was correlated with significantly decreases in the production of the inflammatory mediators such as TNF-α, IL-1β, IL-12, and IFN-γ, while increasing production of the anti-inflammatory cytokine IL-10 in vivo and in vitro. In response to LPS, PAF inhibits ERK1/2 and p38 MAPK activation, which is critical for proinflammatory cytokines production. Furthermore, PAF upregulates SOCS1 and SOCS3, which are essential for cross-talk inhibition in LPS-induced cytokine signaling. Taken together, these results suggest that PAF may provide protection against endotoxic shock via a complex mechanism involving modulation of inflammatory and anti-inflammatory mediators, as well as balanced regulation between activation and subsequent deactivation of the signaling pathways in response to LPS.
MAGUK-controlled CARMA1 and BCL-10 turnover propose a new mechanism for NF-κB inactivation in lymphocytes (33.31)
Authors: Moreno-Garcia Miguel E , Sommer Karen , Rawlings David J 
Published: January 2023

Abstract
In lymphocytes, the antigen receptor utilizes a unique scaffolding molecule, CARMA1, to organize an oligomerization cascade that ultimately activates NF-kappaB. Activation of CARMA1 is characterized by conformational changes that expose binding sites to downstream effectors, including BCL10. We found that CARMA1 activation induces its own turnover, and also drives the turnover of BCL10. In B and T cell lines, activated CARMA1 is post-translationally modified by K48-linked polyubiquitin chains, and its degradation is blocked by proteasome inhibitors. CARMA1 ubiquitination was enhanced in vitro by E3 ubiquitin protein ligases cIAP2 and NEDD4 (but not Cbl-b, ITCH, or beta-TrCP). The MAGUK region of CARMA1 plays a unique role in mediating these events as the SH3 and GUK domains are main ubiquitin acceptors, and deletion of a domain (HOOK) located between SH3 and GUK was sufficient to induce E3 recruitment and constitutive ubiquitination. Additionally, we show that CARMA1 promoted parallel ubiquitination and degradation of BCL10 via a TAK1-dependent mechanism. Functionally, we demonstrated that over-expression of cIAP2 reduced the CARMA1-dependent NF-kappaB activation in antigen receptor stimulated lymphocytes. We hypothesize that up-regulation of E3 ligases by NF-kappaB provides a feed-back control mechanism to shut-down NF-kappaB activation by degrading the CARMA1 scaffold and associated downstream effectors including BCL-10.
This work was funded by NIH 5RO1HD37091 and 5RO3TW007322, and CRDF UKB2-2831-06.
Apoptosis signal-regulating kinase (ASK)-1 mediates apoptosis in B cells (34.6)
Authors: Mizuguchi Junichiro , Takada Eiko , Furuhata Masae 
Published: January 2023

Abstract
Engagement of membrane immunoglobulin (mIg) on B cells results in reduction of the mitochondrial membrane potential (ƒ¢ƒμm) and apoptosis, which plays a crucial role in the regulation of immune responses. In this study, we show that the apoptosis signal-regulating kinase 1 (ASK1)-JNK1 signaling pathway participates in mIg-induced apoptosis in normal B cells as well as WEHI-231 B lymphoma cells. Stimulation of WEHI-231 cells with anti-IgM induces phosphorylation and subsequent activation of ASK1, leading to JNK activation. Anti-IgM stimulation produces superoxide anions (O2-), accompanied by loss of ƒ¢ƒμm and an increase in cells with sub-G1 DNA content. Anti-IgM-induced O2- production, loss of ƒ¢ƒμm, and increase in the sub-G1 fraction were all reduced substantially in WEHI-231 cells overexpressing a dominant-negative form of ASK1, compared with control vector alone. The mIg-mediated O2- production, loss of ƒ¢ƒμm, and increase in the sub-G1 fraction were partially abrogated by the reactive oxygen species scavenger N-acetyl-L-cysteine (NAC). Similarly to WEHI-231 B lymphoma cells, the mIg-mediated apoptotic features were moderately compromised in mouse ASK1-deficient B cells. Taken together, these results suggest that mIg engagement induces JNK activation through ASK1 activation, resulting in production of O2- that leads to loss of ƒ¢ƒμm and finally to apoptosis.
Granzyme B is Important in the Control of B Cell Homeostasis (34.7)
Authors: Zhang Yingyu , xu guangwu , Shi Yufang 
Published: January 2023

Abstract
The role of granzyme B in the homeostasis of B cells is unknown. In our study, splenomegaly with increased B number was observed in Granzyme B deficient (gzb-/-) mice over 8 months age along with significantly increased B cells in the thymus. Moreover, gzb-/- mice over 6 months old have considerably longer intestines with accumulation of lymphocytes in the lamina propria. Serum levels of immunoglobulin isotypes dramatically increased in mice over 4 months old. However, no significant increase was observed in serum Th1/Th2 cytokine levels or in vitro T cell functions . Flowcytometry analysis of B cells in the thymus and spleen from gzb-/- mice showed similar characters to B cells from wild type spleen. Bone marrow transplantation of bone marrow from wild type mice to gzb-/- mice partially corrected the abnormalities observed suggesting that the critical change may lie in the hematopoietive system. In vivo BrdU staining uncovered an increased population of BrdU positive CD45- cells in the spleen. In addition, the percentage of BrdU positive B cells also slightly increased indicating possible role of granzyme B in the control of B cell homeostasis possibly through the abnormal function of this CD45- population of cells. Moreover, coculture of freshly isolated or activated CD8+ T cells with B cells did not show increased cell death in the B cells from gzb-/- mice. Our results showed the importance of granzyme B in the control of B cell homeostasis especially in the intestinal mucosa.
Indigenous opportunistic bacteria inhabit mammalian gut-associated lymphoid tissues for mucosal antibody-mediated symbiosis (39.11)
Authors: Obata Takashi , Goto Yoshiyuki , Shibata Naoko , Sato Shintaro , Kunisawa Jun , Kiyono Hiroshi 
Published: January 2023

Abstract
The indigenous bacteria of the gastrointestinal (GI) tract create natural cohabitation niches together with mucosal antibodies (Abs) such as secretory IgA (S-IgA). However, the nature of this symbiosis is still not well understood. Here we report that opportunistic bacteria, mostly Alcaligenes spp., specifically inhabit the gut-associated lymphoid tissues (GALT), namely Peyer's patches (PPs) and isolated lymphoid follicles (ILFs) of naive, specific-pathogen-free (SPF) but not germ-free (GF) mice. Consistent with this result, antigen-specific Ab-producing cells are present in the mucosal (e.g., PPs) but not systemic compartment (e.g., spleen). In the absence of antigen-specific mucosal Abs in PPs, intra-tissue inhabited Alcaligenes were greatly diminished. Thus, Alcaligenes uniquely inhabits PPs by inducing PP antigen-specific Ab production; this creates an optimal symbiotic environment on the interior of PPs.
Distinct roles of dendritic cells and macrophages in B cell class switching (39.12)
Authors: Xu Wei , Dullaers Melissa , Oh Sangkon , Banchereau Jacques 
Published: January 2023

Abstract
Immunoglobulin A (IgA) provides the first line of immune protection at mucosal surface. Dendritic cells (DCs) can induce naïve B cell class switching towards IgA in a T cell -independent manner. We questioned whether resident macrophages, antigen presenting cells in tissue, can also shape protective mucosal immunity. Human DCs (by IL-4 and GM-CSF) and macrophages (by M-CSF) were generated from monocytes of the same donor. Autologous IgD+CD27- naïve B cells were activated by anti-IgM (to mimic antigen engagement with BCR), CpG and IL-2, and cultured with DC or macrophages on L cell-coated plates (to mimic stoma environment). We showed here that both anti-inflammatory CD163+ macrophages and DCs induced naïve B cell proliferation and differentiation towards CD38+CD27+CD20- plasmablasts. However, CD38+ cells induced by macrophages showed more terminally differentiated CD138+ plasma cells than those induced by DCs. Macrophage-induced plasma cells preferentially expressed surface IgA whereas DC-induced plasma cells preferentially expressed surface IgG. ELISA showed that macrophage-stimulated B cells produce more IgA (both IgA1 and IgA2) than DC-stimulated B cells which produce more IgG. Macrophage-primed plasma cells also expressed more CCR10 than those primed by DCs. Both tonsil and colon sections confirmed that CD138+ plasma cells were surrounded prevalently by CD163+ resident macrophages. Our data suggest a previously unrecognized mechanism by which macrophages help B cells to establish protective mucosal immunity.
The potential role of locally induced matrix metalloproteinase 3 in respiratory mucosal immunity (39.17)
Authors: Guo Xueshui , Knudsen David E. B. , Wang Xiuqing 
Published: January 2023

Abstract
Recent studies suggest that matrix metalloproteinase 3 (MMP3) is involved in intestinal immunity against bacterial infections as well as in immune cell migrations in delayed hypersensitivity. The goal of this study is to assess the potential role of MMP3 in the development of mucosal immunity at respiratory tract using CpG oligodeoxynucleotide (ODN) as a model system. Groups of BALB/c mice were administrated intranasally with either CpG ODN or GpC ODN or PBS. MMP3 was up-regulated at both 1 and 3 days post immunization in bronchoalveolar lavages (BAL) and respiratory mucosal tissues of CpG ODN immunized mice as determined by ELISA, Western blot and immunohistochemistry (IHC) staining. Furthermore, an increase of both CD11c+ antigen presenting cells and CD4+ T cells was observed in lungs of CpG vaccinated mice compared with GpC ODN or PBS controls. To confirm that MMP3 expression is associated with increased immune cell migration in lungs, mice were treated with MMP3-specific inhibitor II 6hr after CpG immunization. Lung tissues were collected 3 days later and subjected to IHC analysis to determine the expression of MMP3 and the number of CD11c antigen presenting cells and CD4+ T cells. Results showed that MMP3 expression was significantly reduced after treatment with inhibitor II, suggesting that MMP3 inhibitor effectively reduced the expression of MMP3. Accordingly, a reduced number of CD11c+ antigen presenting cells and CD4+ T helper cells was observed in inhibitor-treated mice, indicating a possible role of MMP3 in immune cell migration. Ongoing experiments are focused on validating these observations and investigating the mechanistic basis of this MMP3-associated mucosal immunity. It is anticipated that the results may provide new insights on the molecular basis of mucosal immunity at respiratory tract. (Supported by NSF/EPSCoR EPS-0091948)
Distinct mucosal microenvironments differentially regulate memory T cell differentiation state and maintenance (39.20)
Authors: Fraser Kathryn , Casey Kerry A , Vezys Vaiva , Masopust David 
Published: January 2023

Abstract
T cell location and differentiation state are critical factors involved in protection against viral infection. We found that the phenotype of LCMV-specific CD8 and CD4 T cells varied by location, even amongst different mucosal tissues. Virus-specific CD8 T cells upregulated αE integrin and downregulated Ly6C in the small intestine but this did not occur in the spleen, lung, large intestine, or vaginal mucosa. αE integrin was required for maintenance of CD8 T cells in the small intestine IEL (see Casey et al. abstract). TGF β was responsible for inducing this tissue-specific phenotype. Interestingly, virus-specific CD4 T cells did not modify αE integrin and Ly6c in response to TGF β. Virus-specific CD4 T cells exhibited a decrease in αE integrin expression compared to CD8 T cells and this correlated with decreased maintenance of memory antigen-specific CD4 T cells within this compartment. Taken together, these data may explain why the abundant CD4 T cell effector response was poorly maintained specifically within the small intestine epithelium and highlights a mechanism by which tissue microenvironment regulates maintenance and compartmentalization of T cells in mucosal tissues.
CD69 and CD103 cooperatively regulate CD8 T cell responses in the lungs after viral infection (39.25)
Authors: Lee Young-Tae , Suarez-Ramirez Jenny E , Redman Jason M , Aguila Carolina C , Hadley Gregg A , Cauley Linda S 
Published: January 2023

Abstract
T cell mediated immunity to influenza infection disappears within a few months, even though large numbers of virus-specific memory CD8 T cells remain in the circulation for at least two years. It has been suggested that antigen persistence may play an instrumental role in protective cellular immunity. This idea is supported by the presence of activated virus-specific CD8 T cells in the respiratory tract during the months following infection, when processed influenza antigens are presented to virus-specific CD8 T cells in the draining lymph nodes. A majority of the endogenous virus-specific CD8 T cells that were at the mucosal surface of the lungs one month after infection expressed both CD69 and CD103. In contrast, bystander memory CD8 T cells that entered the lungs during parabiosis did not acquire this phenotype. We have crossed CD69KO and CD103KO mice with F5 TcR transgenic mice which are specific for the influenza NP peptide. Transfer studies show that CD103-deficiency results in reduced numbers of CD69+ NP-specific CD8 T cells in the lungs. In contrast, CD69-deficiency results in slightly delayed T cell activation followed by a late accumulation of CD103-negative NP-specific CD8 T cells in the lung parenchyma. This work was supported by NIH grants AI065895 & AI071213 (LSC), RO1 AI-36532 (GH).
TRAIL-expressing CD8+ regulatory T cells participate in the maintenance of ocular immune privilege (39.40)
Authors: Brincks Erik L , Ferguson Thomas A , Griffith Thomas S 
Published: January 2023

Abstract
Immunological tolerance to antigens encountered in the eye, the prototypic immune privileged site, inhibits potentially damaging immune responses that would otherwise be initiated to these antigens at other anatomical locations. The induction of tolerance depends on the FasL-mediated apoptotic death of inflammatory cells that enter the eye in response to antigenic challenge. Moreover, the tolerance is not due to the failure to prime, but is mediated by the generation of CD8+ regulatory T cells (Treg) that can transfer tolerance to a naïve recipient. The present study investigated the mechanism of action of the induced CD8+ Treg. Unlike wildtype (WT) mice, TRAIL-/- or DR5-/- mice did not develop tolerance to antigen injected into the eye, even though the responding lymphocytes underwent apoptosis in the eyes of all mice. We also found that splenocytes from tolerant WT mice produced significantly less IFN, compared to TRAIL-/- mice, after restimulation. Interestingly, CD8+ T cells from TRAIL-/- mice were unable to transfer tolerance to naïve recipient WT mice, but CD8+ T cells from WT or DR5-/- mice could transfer tolerance. Subsequent investigation found that tolerant animals contained CD8+ Treg cells capable of killing antigen-pulsed splenocytes via TRAIL. Together, our data indicate that CD8+ Treg enforce tolerance in a TRAIL-dependent manner to inhibit inflammation in the eye.
Estrogenic microenvironment influences immunity (39.41)
Authors: Papenfuss Tracey L , Taylor Cassandra L 
Published: January 2023

Abstract
Estrogens affect the immune system and immune-mediated/autoimmune diseases. We have found that in vivo estriol (E3) alters dendritic cell (DC) phenotype and function that impact CD4+ T cells. This study evaluates the in vitro effects of E3 (and 17-beta estradiol; E2) on immune function. Spleen (SPL) and lymph node (LN) cells from C57BL/6 mice were CFSE stained and cultured for 3-5 days with media, 100 uM E3 or 100 uM E2 and stimulated with media, anti-CD3 or conA. Decreased proliferation was seen in the E3 (and E2) treated cells as demonstrated by increased mean fluorescence intensity (MFI), fewer daughter cell populations and decreased cell yield in both anti-CD3 and conA stimulated groups. Decreased cell number was not due to cell death as determined by trypan blue and 7-AAD staining. E3 and E2 cultures produced less IL-10 and IL-12p40 by ELISA and phenotypic evaluation of CD11c+ and CD11b+ cells by flow after 48 hours of in vitro E3 stimulation demonstrated only slight effects of E3 on CD80, CD86, PD-L1 and PD-L2. Interestingly, E2 treated cells showed increased CD80 and/or CD86 expression in CD11c+ and CD11b+ cells in the LN and SPL. These studies demonstrate that estrogens can have anti-proliferative effects on SPL and LN populations and influence cytokine and costimulatory molecule expression on antigen presenting cells. Further studies are necessary to compare the in vitro and in vivo effects of estrogens such as E3.
Oral tolerance induction is defective during the neonatal period in the mouse (39.42)
Authors: KIM MEE KUM , LEE JOON YOUB , PURTON JARED F , MARTIN CHRISTOPHER , KIM DAVID M , SURH CHARLES D 
Published: January 2023

Abstract
Congenital T cell (T)-deficient mice, such as RAG-1- or SCID mice, succumb to inflammatory bowel disease (IBD) upon adoptive transfer of syngenic naive T cells as a consequence of chronic inflammation in the intestine from unfettered response to commensal bacterial antigens. Although the prevailing view for the onset of IBD is believed to be the absence of regulatory T cells (Tregs), the finding that donor T cells undergo considerable chronic activation even in the presence of Tregs suggests an abnormality in the presentation of enteric antigens also appears to be involved. To study if such a defect is also evident during the lymphopenic neonatal period, we compared the induction of oral tolerance between B6 neonates and adults to host commensal or exogenously provided nominal Ags by adoptively transferring polylconal or Ag-specific donor T cells. Strikingly, donor T cells in neonatal hosts proliferated much faster and more readily acquired effector function than donor T cells in adults. These finding suggests that oral tolerance in normal mice is acquired later with the development of T immunity.
ERK1/2 and NFκB are key signaling pathways in the regulation of CXCL8 expression and secretion by intestinal epithelial cells in response to P2Y6 receptor activation (39.43)
Authors: Grbic Djordje M , Gendron Fernand-Pierre 
Published: January 2023

Abstract
Extracellular nucleotides are recognized as inflammatory-active molecules. We have investigated the role of extracellular uridine 5'-triphosphate (UDP) and its associated P2Y6 receptor in the secretion of CXCL8 by intestinal epithelial cells. We have also characterized signaling pathways linking UDP to the expression of CXCL8. The effect of the P2Y6 activation by UDP on chemokine expression and release by epithelial cells was determined using combination of western blots, luciferase assays, Q-PCR and ELISA. We have monitored the activation of different signaling molecules by western blots, luciferase assays and EMSA, along with different pharmacological inhibitors. Stimulation of Caco-2 cells with UDP lead to PKCδ and PKCζ, as well as ERK 1/2 and NFκB-p65 phosphorylation. Mutations of the NFκB binding site in the minimal promoter of the human CXCL8 completely abolished the luciferase activity stimulated with UDP. EMSA assays showed the importance of NFκB binding site for the initiation of transcription of CXCL8 by P2Y6. In this study, we showed the most detailed signaling pathway known so far for P2Y6 receptor its implication in UDP stimulate CXCL8 expression and release by intestinal epithelial cells.
The effect of c-Kit inhibition on mast cells in skin, colon, and lung (39.46)
Authors: Trueblood Esther S , Branstetter Daniel , Itano Andrea , Ng Gordon Y. 
Published: January 2023

Abstract
Stem Cell Factor (SCF) signaling via its receptor tyrosine kinase, c-Kit, is vital for mast cell development, function and survival. The effect of inhibition of c-Kit function using subcutaneous administration of a specific blocking monoclonal antibody weekly for up to 28 days was examined in African Green monkeys (Cercopithecus aethiops sabaeus). Treatment-related effects on mast cell populations were evaluated in tissue samples collected from wounded skin and colon biopsies on days 0, 7, 14, 21, and 28 (colon only) and skin, lung, and gastrointestinal tract collected at necropsy on day 28. Mast cells were visualized by Astra blue staining and immunohistochemistry for CD117, tryptase, and/or chymase. Specific c-Kit inhibition resulted in depletion of mast cells in unchallenged skin, colon, and lung after 28 days. Additionally, c-Kit antibody treatment inhibited the injury-induced expansion of dermal mast cells adjacent to wounded skin. Mast cells have been implicated as important mediators in a wide range of inflammatory diseases including asthma, rheumatoid arthritis, inflammatory bowel disease, and fibrosis. This is the first report of use of an antibody to deplete tissue mast cells in relevant organs in non-human primates.
TGF-βRII expressing Peyer’s Patch CD4+ T cells are essential for the induction of mucosal unresponsiveness (39.49)
Authors: Gilbert Rebekah Sims , Fujihashi Kohtaro 
Published: January 2023

Abstract
It has been shown that TGF-β signaling plays key roles in the induction of oral tolerance (OT). We assess the ability of CD4-dominant negative TGF-βRII (TbRII) mice to develop mucosal unresponsiveness to orally administered antigen to understand the role of TGF-β signaling in the early events of OT.
Mice were fed a large dose (30 mg) of OVA and were orally immunized three times at weekly intervals with OVA (1mg) plus native cholera toxin (nCT) one week after tolerization. One week after last immunization plasma and fecal extract samples were collected and mononuclear cells were isolated from spleen, Peyer's Patches (PPs), and mesenteric lymph nodes for analysis by ELISA, ELISPOT and flow cytometry. DTH responses were determined by ear swelling after challenge with OVA. In order to examine the roles of TGF-β signaling in early events of OT induction, CD4+ T cells from C57BL/6 mice were examined for the expression of TGF-βR II at 24-hour intervals for 3 days and on days 5 and 7 after feeding 30mg OVA.
OVA-specific IgG and S-IgA titers in plasma and fecal extracts, respectively, as well as DTH response of OVA-fed TbRII mice were essentially the same as TbRII mice fed PBS. These responses were significantly higher than those of C57BL/6 wildtype mice fed OVA. Expression of TGF-βRII by CD4+ T cells of spleen and MLN of wildtype mice was low or variable, respectively. In contrast, expression of TGF-βRII by PP CD4+ T cells was significantly increased over base-line beginning at 24 hours and continued to remain high one week after tolerization.
These results indicate a critical role for TGF-β signaling in OT induction. Further, our findings may indicate important roles for the PPs in the initiation of mucosal unresponsiveness
This work is supported by NIH grants DE 0176707, DE 012242 and AG 025873.