bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polymorphic alleles of murine CD244 exhibit divergent function in NK cells (89.1)
Authors: westcott jill m , mooney jill m , wakeland edward , schatzle john d 
Published: January 2023

Abstract
CD244 (2B4) is a member of the signaling lymphocyte activation molecule (SLAM) family of receptors and is expressed on all murine NK cells and a subset of CD8+ T cells. The SLAM family of receptors exists as one of two stable haplotypes (b and z haplotype) in common laboratory strains of mice. The b haplotype is associated with C57-derived mouse strains while the z haplotype is found in most other inbred strains. Previous studies have shown that CD244 exhibits inhibitory function in NK cells from C57BL/6 (B6) mice. Here we employ a congenic mouse strain (B6.Sle1b) that differs from the parental solely at a region of chromosome 1 containing the SLAM family of genes to characterize the function of the z haplotype of CD244. We show that the more common haplotype of CD244 exhibits activating function in an SH2D1a dependent manner as evidenced by enhanced lytic activity towards targets expressing the ligand for CD244, CD48. The activating function of the z version of CD244 is due to polymorphic differences that appear to be clustered in the ligand-binding region of the receptor. In addition, we observed differential baseline phosphorylation and adaptor association for each of the CD244 haplotypes in cultured NK cells accounting for their functional differences.
Characterization of the inhibitory receptor CD300a in human neutrophils (89.10)
Authors: Borrego Francisco , Alvarez Yelina , Tang Xiaobin , Coligan John E. 
Published: January 2023

Abstract
To achieve an adequate response, cells of the immune system must be tightly regulated to avoid hypo- or hyper-responsiveness. One of the mechanisms used by the immune system to avoid excessive inflammation is the ligation of inhibitory receptors containing immunoreceptor tyrosine based inhibitory motifs (ITIM). In this report, we show that human neutrophils express the ITIM containing CD300a (IRp60) receptor and that its expression is developmentally regulated. Stimulation of neutrophils with LPS and GM-CSF increased the cell surface expression of CD300a as a result of the rapid translocation of an intracellular pool of the receptor to the cell surface. Cross-linking experiments showed that CD300a inhibited FcãRIIa (CD32a) receptor immunoreceptor tyrosine based activating motif (ITAM) mediated signaling, but not TLR-4 mediated reactive oxygen species (ROS) production. Therefore, in human neutrophils, the ITIM containing CD300a receptor is able to specifically down-modulate ITAM derived signals.
Lithium-induced upregulation of the granzyme B inhibitor proteinase inhibitor 9 (PI-9) in monocytes: Role of glycogen synthase kinase-3? (89.13)
Authors: Classen Carl Friedrich 
Published: January 2023

Abstract
Proteinase inhibitor 9 (PI-9) - the only known natural antagonist of the lymphocyte protease granzyme B (GrB) - is an intracellular serpin expressed in lymphocytes and monocyte-derived cells. By intracellular flow cytometry, we have previously shown that ex-vivo stimulation by lipopolysaccharides leads to upregulation of PI-9 within 24 hours in the monocyte, but not the lymphocyte fraction; this can be inhibited by the NF-kappaB inhibitor pyrrolidin dithiocarbamate (PTDC). Glycogen synthase kinase 3 (GSK) is a lithium-inhibitable, constutitively active serine/threonine kinase that controls a number of intracellular functions, especially those involving NF-kappaB regulated genes. We now asked whether lithium-induced inhibition of GSK might influence expression of PI-9 in monocytes and lymphocytes. A 24 hours incubation assay was done using heparinized full blood of healthy volonteers, and PI-9 expression was analysed by intracellular flow cytometry. We found that lithium chloride leads to PI-9 upregulation in monocytes at a medium concentration (1.5 μM), which could not further be enhanced by higher concentrations (10 or 20 μM lithium chloride). In lymphocytes, no alteration of PI-9 expression was induced. When cells were stimulated by LPS in the presence of lithium, only marginal additional upregulation of PI-9 could be induced. Our data show that a lithium-regulated factor, probably GSK, is involved in PI-9 expression in monocytes, down-regulating PI-9 in resting cells. Since it has been shown that PI-9 over-expression in antigen presenting cells, e.g. dendritic cells, leads to an enhanced immune response, our finding may be relevant for specific immune regulation. Pharmacological manipulation of PI-9 expression may represent a useful tool to study immune regulatory mechanisms as well as for therapy .
A novel role of Janus Kinase 3 and IL-6 in M-CSF-mediated CCL2 production in monocytes and macrophages (89.17)
Authors: Kim Hee-Jung , Wang Yijie , Hunter Melissa , Mo Xiaokui , Marsh Clay B 
Published: January 2023

Abstract
Macrophage Colony-Stimulating Factor (M-CSF) enhances differentiation and survival of monocytes and macrophages. Elevated levels of M-CSF and newly infiltrated monocyte/macrophages are detected in inflammatory diseases and cancer. However, the mechanism regulating M-CSF-mediated mononuclear phagocyte activation remains unclear. Since Janus kinase 3 (JAK3) regulates myeloid development and is a target to regulate the immune system in transplantation and cancer therapy, we determined function of JAK3 in M-CSF-mediated inflammatory responses. JAK3 in monocytes was induced by M-CSF in dose- and time-dependent manner and was higher in macrophages compared to monocytes. A specific JAK3 inhibitor (JANEX-1) suppressed M-CSF-induced CCL2 and IL-10 production in monocytes, but did not reduce M-CSF-induced VEGF production or caspase-3 activation. These results correlated with the observation that bone marrow-derived macrophages (BDMs) from JAK3 KO mice had less M-CSF-induced CCL2 production than WT BDMs, although both BDMs were not different in differentiation based on CD11b and F4/80 staining. Interestingly, exogenous IL-6 augmented M-CSF-induced CCL2 and IL-10 production and enhanced JAK3 expression. Since c-Jun binds the promoter regions of CCL2 and IL-10, we also utilized SP600125 (a specific Jun kinase inhibitor). Both JANEX-1 and SP600125 suppressed M-CSF- and M-CSF/IL-6-induced CCL2 and IL-10 production in a dose-dependent manner, linking JAK3 and JNK signaling pathways. Increased CCL2 may recruit additional mononuclear phagocytes and prolong the inflammatory response, while IL-10 may counter this inflammatory cascade. These data suggest that JAK3 regulation is an important target in chronic inflammatory disease and provides a mechanism by which IL-6 affects these events.
IFN-gamma Limits Peripheral T cell Expansion of Extrathymic T cells. (89.18)
Authors: Blais Marie-Eve , Brochu Sylvie , Perreault Claude 
Published: January 2023

Abstract
When overexpressed under the p56Lck proximal promotor, Oncostatin M induces extrathymic T cell development in the lymph nodes. During LCMV infection, extrathymic (ET) T cells produce copious amounts of IFN-γ and their expansion is precocious but of limited amplitude because of early apoptosis. Moreover, ET T cells show significant apoptosis in uninfected mice. Hence, we sought to understand why ET T cells are more susceptible to apoptosis than thymic T cells. We found that the mitochondrial apoptotic pathway is likely involved in apoptosis of CD4+ ET T cells because of lower Il-7Rα and Bcl-2 levels compared to thymic T cells. In contrast, this deficit was not seen in CD8+ ET T cells. However, CD8+ ET T cells displayed higher Fas and active caspase 8 expression indicating apoptosis via the death receptor pathway. Moreover, we found that ET T cells and thymic T cells in homeostatic peripheral expansion (HPE) shared many similarities: memory phenotype, accelerated turnover and increased susceptibility to apoptosis. Moreover, spontaneous IFN-γ secretion by CD8+ ET T cells leading to massive accumulation in sera was observed. Finally, we found that CD8+ T cell survival was restored during HPE induced with ifngR−/−T cells as well as in ifng−/−ET T cells compared to IFN-γ-responsive T cells. Taken together, these results show that IFN-γ regulates apoptosis of ET T cells T cells in HPE and thereby limits their accumulation in vivo.
A novel role for Ku70 in differential regulation of pro-inflammatory cytokine response to CpG-DNA (89.22)
Authors: Wang Xin , Dragoi Ana-Maria , Riolo Matthew , Peng Michelle (Xiao) , Chu Wen-Ming 
Published: January 2023

Abstract
CpG-DNA or synthetic oligodeoxynucleotides containing CpG motif (CpG-ODNs) strongly activate dendritic cells (DCs) and macrophages to produce proinflammatory cytokines including IL-6, IL-12 and TNF?. It has been suggested that CpG-DNA activates TLR9, which in turn recruits MyD88, IRAK4, IRAK1 and TRAF6, leading to activation of AP-1 and NF-?B, which are critical for immune gene expression. However, whether DNA binding proteins are involved in activation of the CpG-DNA pathway remains elusive. Here we demonstrate that Ku70 is involved in this process. Administration of CpG-ODN into Ku70-deficient mice and in vitro stimulation of bone marrow-derived DCs (BMDCs) as well as bone marrow-derived macrophages (BMDMs) from these mice resulted in defective induction of IL-6 and TNF?. Loss of Ku70 impaired activation of its downstream kinases, the I?B kinase (IKK) and the mitogen-activated protein kinases (MAPKs), by CpG-ODN. Intriguingly, in macrophages ablation of Ku70 largely abrogated IRF1 expression and subsequent IL-12 response to CpG-ODN; in BMDCs Ku70 deficiency only reduced IL-12 response to CpG-ODN at a low dose within early treatments, and had no apparent effects on this response in late treatments. Thus, our results suggest that Ku70 is important for differential regulation of inflammatory cytokine response to CpG-DNA. In addition, we have identified a mechanism for involvement of Ku70 in activation of the CpG-DNA pathway.
CD303 (BDCA-2) mediated inhibition of interferon type I production in plasmacytoid dendritic cells is linked to SYK, BLNK and PKC delta signaling (89.25)
Authors: Röck Jürgen , Schmitz Jürgen , Winkels Gregor 
Published: January 2023

Abstract
CD303 is a calcium dependent type II lectin also known as Blood-Dendritic-Cell-Antigen-2 (BDCA-2) specifically expressed by human plasmacytoid dendritic cells (PDC). We have previously shown that monoclonal antibody (mAb) ligation of CD303 induces mAb endocytosis, calcium mobilization, protein tyrosine phosphorylation and inhibition of type I interferon (IFN I) production in stimulated PDC. Here we show that CD303 signaling and internalization in many aspects resembles B cell receptor (BCR) signaling and internalization. Instead of CD79a and CD79b, CD303 appears to use the Fc-receptor-common-gamma-chain as transmembrane adaptor protein. Like BCR signaling, CD303 triggering leads to SYK and BLNK phosphorylation. Signal transduction most likely involves activation of the phospholipase C-gamma 2, the phosphoinositide-3 kinase and the protein kinase C delta. Therefore, inhibition of IFN I production in stimulated PDC can be mimicked by PMA. Western blotting and peptide mass fingerprinting show that tyrosine phosphorylation occurs at cytoskeletal proteins (actin, alpha/beta-tubulin, profilin, alpha-actinin), proteasome activator subunit and the clathrin heavy chain, indicating clathrin-mediated endocytosis and vesicle trafficking. Finally, CD303 triggering inhibits TNF-alpha and CpG ODN-induced NF-kappa B activation in PDC.
Interplay of Activating and Inhibitory Receptors in NK cells (89.28)
Authors: Das Asmita , Long Eric 
Published: January 2023

Abstract
Natural Killer (NK) cells are lymphocytes capable of killing tumor cells and virus-infected cells without prior sensitization. Each NK cell expresses several different activating and inhibitory receptors. A balance of activating and inhibitory signals delivered by these receptors determines the outcome of NK–target cell interactions. However, it is often difficult to identify the individual contribution of each activating receptor and its susceptibility to inhibition. To avoid this complexity, SC2 insect cells have been transfected with ligands for several activating and inhibitory receptors. CD16 is the only receptor tested that is capable of inducing degranulation and cytokine production. Other receptors, such as NKG2D, LFA-1 enhance CD16-induced responses. Target cell lysis by NK cells requires polarized release of cytotoxic granule. The insect cell system is now being used to test if co-engagement of inhibitory receptors for MHC class I blocks granule polarization, degranulation or both.
Knockout of Mkp-1 enhances the host inflammatory responses to Gram-positive bacteria (89.3)
Authors: Liu Yusen , Wang Xianxi , Meng Xiaomei , Kuhlman Joshua R. , Nelin Leif D. , English B. Keith 
Published: January 2023

Abstract
MAPK phosphatase (MKP)-1 is an archetypal member of the dual specificity protein phosphatase family that dephosphorylates MAPK. We have previously demonstrated that MKP-1 acts as a negative regulator of p38 and JNK in immortalized macrophages after stimulation with peptidoglycan isolated from Gram-positive bacteria. To define the physiological function of MKP-1 in host defense during Gram-positive bacterial infection, we studied the innate immune responses to Gram-positive bacteria using Mkp-1 knockout mice. Here we show that Mkp-1−/− macrophages exhibited prolonged activation of p38 and JNK, but not of ERK, following exposure to either peptidoglycan or lipoteichoic acid. Compared to wild type macrophages, Mkp-1−/− macrophages produced more pro-inflammatory cytokines such as TNF-α and IL-6. Moreover, after challenge with peptidoglycan, lipoteichoic acid, live or heat-killed Staphylococcus aureus bacteria, Mkp-1 knockout mice also mounted a more robust production of cytokines and chemokines, including TNF-α, IL-6, IL-10, and MIP-1α, than did wild type mice. Accordingly, Mkp-1 knockout mice also exhibited greater NO production, more robust neutrophil infiltration, and more severe organ damage than did wild type mice. In response to challenge with heat-killed S. aureus, Mkp-1 knockout mice exhibited a substantially higher mortality rate compared to wild type mice. Our studies indicate that MKP-1 plays a critical role in the inflammatory response to Gram-positive bacterial infection. MKP-1 serves to limit the inflammatory reaction by inactivating JNK and p38, and in the absence of MKP-1 the exaggerated inflammatory response results in devastating consequences to the host.
Natural killer cells from mice deficient in protein kinase C-theta have reduced production of interferon-gamma after stimulation with interleukin-12 (89.32)
Authors: Bourque Karen M. , Kasaian Marion T. 
Published: January 2023

Abstract
NK cells play a key role in innate immune responses. PKC𝛉 is important for T cell activation, but is also expressed in NK cells. NK cells from PKC𝛉 −/− and WT mice were enriched from splenocyte cultures by incubation with IL-15 for one week and then treated for 24 hours with IL-12 or IL-18 to induce IFNγ production. Cytotoxicity of NK cells from PKC𝛉 −/− and WT mice was activated in vivo with poly I:C or in vitro with cytokines, and target cell specific killing measured by 51chromium release assay. NK cell-enriched splenocytes from PKC𝛉 −/− animals produced significantly less IFNγ in response to IL-12, but not in response to IL-18. In contrast, NK cell mediated cytotoxicity was unaffected by the absence of PKC𝛉. T cells, which can also make IFNγ, were not a source of IFNγ in these experiments, nor did they affect the ability of NK cells to produce it. No differences in spleen NK cell numbers or viability were detected. NK cells from PKC𝛉 −/− mice also exhibited normal expression of IL-12Rβ1, and STAT4 proteins and normal IL-12-induced phosporylation of STAT4. Phosphorylation of T538 within the catalytic domain of PKC𝛉 was detectable in NK cells from WT mice, but was not enhanced by IL-12. IFNγ mRNA increased to a similar extent in NK cells from WT and PKC𝛉 −/− mice in response to IL-12. IFNγ mRNA stability was unaffected by the absence of PKC𝛉. These findings indicate a role for PKC𝛉 in the post-transcriptional regulation of IL-12-induced IFNγ.
KIR2DL4 signals downstream functions in human NK cells through two distinct structural elements (89.34)
Authors: Miah Shah Md. Shahjahan , Hughes Tracey L. , Campbell Kerry S. 
Published: January 2023

Abstract
KIR2DL4 is a member of the killer cell Ig-like receptor (KIR) family expressed on human natural killer (NK) cells. A transmembrane Arginine (R) in KIR2DL4 binds to the transmembrane adaptor FcεRI-γ and stimulates potent IFN-γ production and weak cytolytic activity. In this study, we have found that the mutation of transmembrane R to Glycine (G) (RG mutant) in KIR2DL4 abrogates FcεRI-γ association, IFN-γ production, cytolytic activity and calcium responses. We further found that crosslinking of KIR2DL4 activates the MAP kinases JNK and ERK, as well as the NF-κB pathway in KHYG-1, a human NK-like cell line. Engagement of KIR2DL4 also activates the transcription of a variety of cytokine and chemokine genes including TNF-α, IFN-γ, MIP1α, MIP1β, IL-8 and RANTES. Pharmacological inhibitors of JNK and MEK1/2 blocked IFN-γ and IL-8 production, suggesting that these MAP kinases are regulating KIR2DL4 mediated cytokine production. Surprisingly, we have found that the RG mutant of KIR2DL4 still activates MAP kinases and the NF-κB pathway and differentially regulates chemokine production. In conclusion, our data suggests that the activating functions of KIR2DL4 are mediated by two distinct pathways in NK cells:through transmembrane association with FcεRI-γ andthrough its cytoplasmic tail, which is independent of the transmembrane R.
This work was supported by National Institutes of Health Grant CA-100226 to K.S.C.
Disparity in mycobacterium tuberculosis-induced IL-12 release in dendritic cells and macrophages is due to utilization of distinct Toll-like receptors (89.35)
Authors: Pompei Luca , Jang Sihyug , Zamlynny Beata , McBride Amanda 
Published: January 2023

Abstract
In the pursuit of understanding the molecular basis for a differential release of interleukin (IL)-12 between dendritic cells (DCs) and macrophages in response to Mycobacterium tuberculosis (Mtb), we first evaluated the expression of IL-12p35 and IL-12p40. The two cell types showed similar transcription levels of IL-12p35, while IL-12p40 mRNA was expressed in a rapid and enhanced manner only in murine bone-marrow DCs. An analysis of the remodeling at the nucleosome 1 of the IL-12p40 promoter also provided evidence of a rapid and extensive accessibility to the transcription factor NF-kB in DCs. Despite restoring the impaired Mtb-dependent release of IL-12, addition of interferon (IFN) 2 □ or removal of IL-10 did not affect the extent of remodeling in the IL-12 promoter of macrophages. By evaluating the IL-12p40 remodeling and release in knock-out mice models we demonstrate that DCs mainly rely on signaling from toll-like receptor (TLR)9 for their extensive Mtb induced IL-12 expression. Moreover the TLR9 ligand CpG induced extensive remodeling and release of IL-12p40 in comparison to a TLR2 agonist. Our work suggests a different handling of Mtb from the two cell types where TLR9 engagement occurs prevalently in DCs and leads to high expression of IL-12 and supports the rising opinion, which favors a role for TLR2 in Th2 type responses.
Acute alcohol induces SOCS3 and SOCS1 via STAT3 activation in human monocytes (89.36)
Authors: Norkina Oxana , Dolganiuc Angela , Kodys Karen , Mandrekar Pranoti , Szabo Gyongyi 
Published: January 2023

Abstract
Consumption of moderate amounts of alcohol inhibits the inflammatory responses in human monocytes. Our study reports the effect of in vitro and vivo alcohol treatment on pathways leading to expression of SOCS3 and SOCS1, potent inhibitors of cytokine signaling. Human monocytes treated in vitro with 25–50mM of alcohol for 3–24h had significantly increased SOCS1 and SOCS3 mRNA compared to controls, similar to in vivo alcohol-exposed cells. Activation of STAT3, a regulator of SOCS3 and SOCS1, was induced by alcohol, as indicated by STAT3 tyrosine and serine phosphorylation and DNA binding. We found that STAT3 activation by alcohol can be directly regulated by Src tyrosine kinases and through a crosstalk with MAPKs. Acute alcohol treatment activated Src kinases in monocytes as detected by increased Src Tyr 416 phosphorylation. Consistent with Src kinases activation, alcohol decreased the levels of the inactive form of Lyn kinase, represented by phosphorylation at the Tyr 507. Using specific inhibitors, we identified that STAT3 activation by Src kinases occurred directly at Tyr 705 or indirectly at Ser 727 via JNK and p38, but not ERK MAP kinases. Our finding that acute alcohol activates Src-STAT3 pathway and induces SOCS3 and SOCS1 indicates that the immunosuppressive effects of acute alcohol may influence multiple signaling pathways employed by inflammatory cytokines and regulated by SOCS3 and SOCS1.
TLR5 is not critical for humoral immune responses to purified flagellin or co-administered antigens (89.37)
Authors: Sanders Catherine J. , Akira Shizuo , Gewirtz Andrew T. 
Published: January 2023

Abstract
A problem in developing vaccine adjuvants is that their effectiveness may be inherently tied to TLR activation and consequently “cytokine storms”. To examine whether this applied to the TLR5 ligand flagellin, a MyD88-dependent adjuvant, we compared immune responses of TLR5KO mice and WT littermates to purified flagellin or flagellin+OVA. Flagellin-treated TLR5KO mice lacked induction of serum IL-12(p40), TNFα, RANTES, IL-17, Eotaxin, or MIP-1β measured over a 24 hour period compared to WT, yet had reduced though significant serum cytokine levels of KC (9%), IL-1α (53%), IL-6 (24%), MCP-1 (22%), and G-CSF (16%) (% KO of WT). TLR5KO mice also lacked detectable activation of splenic DC and had modestly diminished Ab titers to flagellin (26% of WT) or OVA (40% of WT). These data indicate flagellin’s adjuvanticity does not require TLR5, detectable DC activation, or the relatively high serum cytokine levels found in WT mice. In contrast, MyD88KO mice exhibited complete absence of flagellin-induced cytokines and Abs. Such data suggest the positive antibody response in TLR5KO mice may have resulted from a TLR5-independent pathway of flagellin recognition, whose activation and subsequent immune events promote adaptive immunity. These data support and expand the concept that TLR ligands can promote antibody responses by means not requiring the TLRs thought necessary for their innate immune recognition.