bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential regulation of type 2 innate lymphoid cells by IL-25 and IL-33 (P6254)
Authors: Chen Chien-Chang , Iijima Koji , Kobayashi Takao , Kita Hirohito 
Published: January 2023

Abstract
Type 2 Innate Lymphoid Cells (ILC2s) are a novel innate cell populations that plays important roles in Th2-type immune response. They are lineage-negative, CD44+ and require IL-7 signal during their development. ILC2s produce type 2 cytokines in response to IL-33 in vitro. Animal studies demonstrated the production of type 2 cytokines by ILC2s after intranasal administration of IL-33. In addition to IL-33, IL-25 is also able to stimulate ILC2s to secret type 2 cytokines. However, detail mechanism to explain how ILC2s response to IL-33 and IL-25 has been unknown. The goal of this project is to examine the roles of IL-33 and IL-25 in proliferation and activation of ILC2s. We cultured lung cells with IL-33+IL-7 or IL-25+IL-7 and examined the production of IL-5 and IL-13. Lung ILC2s produced a large quantity of IL-13, but little IL-5 and highly expressed ICOS and ST2 in response to IL-25+IL-7 in vitro. When incubated with IL-33, the majority of ILC2s secreted both IL-5 and IL-13 and expressed intermediate level of ICOS and ST2. When IL-25 was administered intranasally to IL-13-GFP mice, a large proportion of ILC2s highly expressed IL-13-GFP. When IL-33 was administered, ILC2s showed modest expression of IL-13-GFP. These findings suggest that IL-33 and IL-25 are involved in overlapping but maybe different immunological and pathological process.
CXCL17 is a novel macrophage recruitment factor (P6215)
Authors: Burkhardt Amanda , Maravillas-Montero Jose Luis , Carnevale Christina , Selman Moises , Zlotnik Albert 
Published: January 2023

Abstract
Chemokines chemotactic molecules that regulate the development of immune responses, There are 48 members of this human gene superfamily and for most we have a good understanding of their biology. Some, however, remain poorly characterized including CXCL17 which was the last ligand of this superfamily to be described. Recently, we reported that CXCL17 is an important mucosal chemokine that exhibits antimicrobial activity and is elevated in the bronchoalveolar lavage fluid (BALf) of patients with idiopathic pulmonary fibrosis. We have now explored the chemotactic properties of CXCL17. In vitro, CXCL17 induces chemotactic responses in monocytic cell lines and in macrophages. We also analyzed CXCL17 effects in vivo and observed that it recruits F4/80+ macrophages to the peritoneal cavity. We have obtained a Cxcl17 (-/-) mouse and observed that it exhibits decreased numbers of macrophages is several mucosal tissues when compared to wild type mice. We conclude that CXCL17 is an important macrophage chemotactic factor. In addition, this information indicates that CXCL17 is likely involved in macrophage recruitment both under homeostatic conditions and also during inflammatory responses. Importantly, CXCL17 is likely to participate in human disease as we have already observed high levels of this chemokine in IPF. Taken together, our data strongly suggests that CXCL17 may be involved in human inflammatory diseases that affect the mucosa.
Cobalt-chrome micro-particles induce a robust MyD88-independent, Caspase1-dependent type 2 immune response (P1266)
Authors: Mishra Pankaj , Palma Mark , Millman Ariel , Hallab Nadim , Beebe Kathleen , Benevenia Joseph , Kanneganti Thirumala-Devi , Gause William 
Published: January 2023

Abstract
Wear debris particles associated with prosthetic devices may cause inflammation. In our previous study, we demonstrated that micrometer size Titanium particles induce a robust innate and adaptive type 2 in vivo immune response. In this study, we examined the size and mechanisms of particle induced type 2 inflammation, using Cobalt Chrome (COCR). Intra-peritoneal injection of 50 mg COCR (&gt;10micron) still induced a type 2 innate response with marked increases in M2 macrophages, neutrophil and eosinophils independent of MYD88/TRIFF signaling pathways. We observed a marked decrease in the infiltration of neutrophil and M2 macrophages in Caspase-1-/- mice compared to wild type mice suggesting an essential role for inflammasome-mediated pathways. Intra peritoneal injection with smaller size COCR particles (&lt;10micron) showed less infiltration of Th2 innate cells compared to the large size COCR particle (&gt;10micron). We also examined the adjuvant nature of COCR particles by immunizing mice with COCR microparticles + OVA peptide after transfer of CFSE-labeled OVA specific DO11.10 CD4+ T cells. After 7 days marked increases in OVA-specific T cell proliferation and IL-4 production was observed compared to mice immunized with OVA alone. These studies indicate that induction of the type 2 immune response is triggered by solid particles alone similar in size to macroparasites, independently of MYD88 signaling and at least partially dependent on inflammasome activation.
Flagellin induces antibody responses through a Toll-like receptor 5 and inflammasome independent pathway (P1274)
Authors: Lopez-Yglesias Americo , Lai Marvin , Quarles Ellen , Zhao Xiaodan , Strong Roland , Smith Kelly 
Published: January 2023

Abstract
Flagellin is a potent immunogen that is recognized by TLR5 and Naip5/6, activates the innate immune system, and elicits strong T and B cell responses. The adaptor protein MyD88 is critical for both TLR5, as well as IL-1β and IL-18 receptors, major downstream mediators of the Naip5/6. Herein, we define the role of known flagellin receptors and MyD88 in antibody responses generated towards flagellin. To characterize the innate immune components that regulate isotype specific antibody responses, we used several genetically deficient mice: Naip5, caspase-1, MyD88, and TLR5/caspase-1. Using purified flagellin from S. Typhimurium, we tested serum cytokine responses in mice after i.p. injections. We observed that serum levels of IL-12/23p40 were TLR5-dependent, IL-18 levels were Naip5-dependent, and KC and IL-6 levels were dependent on both. We dissected antibody responses produced towards both flagellin and OVA via a prime/boost regimen. We show that IgG2c responses towards flagellin are TLR5-, and inflammasome-dependent. While IgG1 levels were partially dependent on TLR5 and the inflammasome, a substantial IgG1 response was induced through an undefined pathway. Conversely, the adjuvant effects of flagellin extrinsic antigen OVA are TLR5 and inflammasome dependent. Our results demonstrate a novel third pathway of flagellin recognition that contributes to antibody production. Further characterization of this pathway will be useful for flagellin-based vaccine design.
STING, the sensing of cytosolic DNA and innate immune-mediated inflammatory disease (P1256)
Authors: Ahn Jeonghyun , Gutman Delia , Saijo Shinobu , Barber Glen 
Published: January 2023

Abstract
Autoimmune diseases such as systemic lupus erythematosus (SLE) affect millions worldwide, the cause of which remains unknown. SLE and diseases such as Aicardi-Goutieres syndrome (AGS) are characterized by the overproduction of cytokines such as type I interferon (IFN), speculatively by chronic infection or self nucleic acids. Mice lacking DNAse II die during embryonic development through comparable autoimmune disease since phagocytosed DNA from apoptotic cells cannot be adequately digested and intracellular host DNA sensors are activated resulting in the production of a variety of cytokines including type I IFN. The cellular sensor responsible for triggering DNA-mediated inflammation aggravated autoimmune disease remains to be determined. However, we report here that STING (Stimulator of Interferon Genes) complexes with phagocytosed undigested DNA and controls innate immune signaling events that facilitate such events. DNase II-dependent autoimmune embryonic lethality was rescued by loss of STING function and polyarthritis completely prevented since cytosolic DNA failed to trigger cytokine production. Accordingly, loss of STING similarly alleviated Trex1-dependent lethal inflammatory myocarditis in mice, a model for AGS. Our data provides molecular insight into the causes of DNA-mediated inflammation-dependent autoimmune disorders and affords a new target that could plausibly be therapeutically controlled, to help prevent such diseases.
Non-canonical inflammasome activation of Caspase-11 protects against cytosolic bacteria (P1262)
Authors: Aachoui Youssef , Leaf Irina , Hagar Jon , Fontana Mary , Campos Cristine , Zak Daniel , Tan Michael , Cotter Peggy , Vance Russell , Aderem Alan , Miao Edward 
Published: January 2023

Abstract
Caspases are either apoptotic or inflammatory. The inflammatory Caspases-1 and -11 trigger pyroptosis, a form of programmed cell death. Whereas both can be detrimental in inflammatory disease, only Caspase-1 has an established protective role during infection. Here, we report that Caspase-11 is required for innate immunity to cytosolic, but not vacuolar, bacteria. Although Salmonella typhimurium and Legionella pneumophila normally reside in the vacuole, specific mutants (sifA and sdhA, respectively) that aberrantly enter the cytosol triggered Caspase-11 in vitro. This detection enhanced clearance of S. typhimurium sifA in vivo in infected mice. Similarly, Caspase-11 triggered pyroptosis after infection by Burkholderia species, which naturally invade the cytosol. Burkholderia mutants that lack the type III secretion system remain in the vacuole and are not detected through Caspase-11. While C57BL/6 mice could survive infection with B. pseudomallei, Casp11-/- mice rapidly succumbed. B. thailandensis is related to B. pseudomallei, but is normally avirulent as C57BL/6 mice survive infection with 10^7 cfu intraperitoneally; strikingly, Caspase-11 deficient mice succumbed to only 100 bacteria within 3 days. Thus, Caspase-11 is critical to surviving exposure to ubiquitous environmental pathogens that escape into the cytosolic compartment.
A role of Zeb2 in the development of terminally differentiated effector T cells (P1434)
Authors: Best John , Seuntjens Eve , Huylebroeck Danny , Goldrath Ananda 
Published: January 2023

Abstract
Zeb2 (also known as Zfhx1b and Sip1) is a DNA-binding multi-zinc-finger transcription factor found to play a significant role in the development of cells both early in neuronal differentiation and in cancer metastasis. By binding dual E2 box enhancer elements, Zeb2 acts primarily as a transcriptional repressor and may inhibit E-protein DNA binding, although it is known to act also as a transcriptional activator. Zeb2 also binds activated Smads, the co-repressor CtBP and the NuRD chromatin remodeling complex but not all of its functions may necessarily depend on each of these interactions. While the closely related family member, dEG1/Zfhx1a/Zeb1, is known to plays an early role in lymphocyte development, the function of Sip1 in T lymphocytes remains unknown. We find that Zeb2 is upregulated in activated T cells and that antigen specific T cells show diminished expansion during an immune response. Zeb2 is selectively expressed and necessary for the development of a subset of terminally differentiated CD8+ T cells. We are currently assessing the interplay between Zeb2 and E-proteins in differentiation of naïve CD8+ T cells to cytotoxic effector cells.
Identification of eomesodermin-expressing innate-like T cells in adult humans (P1436)
Authors: Gombert Jean-Marc , Jacomet Florence , Basbous Sara , Levescot Anais , Robin Aurélie , Roy Lydia , Giraud Christine , Barra Anne , Guilhot François , Herbelin André 
Published: January 2023

Abstract
Innate-like CD8(+) T cells have been recently described in mice. These cells express NK cell markers with high levels of the transcription factor Eomesodermin (Eomes(br)) and rapidly produce IFN-γ in response to IL-12 and IL-18 stimulation without previous exposure to antigen. To date, only a single study in human has investigated Eomes(br) innate-like T cells which were found in small numbers in fetal spleen and cord blood. In mice, their generation depends on IL-4 expressing invariant NKT (iNKT) cells. Here, we identified a similar subset of T cells, mainly CD8(+) T cells, in PBMC from healthy adult individuals that have increased expression of Eomes. They harbor a marked innate phenotype as attested by a higher frequency of perforin(+) and NK-like (CD158(+) and/or CD159(+)) cells, as compared with total T cells. Likewise, they preferentially produce IFN-γ in response to stimulation by IL-12 and IL-18. Remarkably, in patients with chronic myeloid leukemia (CML), a disease known to be associated with a deficiency in IL-4 expression by iNKT cells, the size of Eomes(br) innate-like T cells is severely impaired. and they have lost the capacity to produce IFN-γ after stimulation with IL-12 and IL-18. These impairments together with the deficiency in IL-4 expression by iNKT cells are corrected in CML patients having achieved complete remission. Altogether, these results demonstrate the presence of Eomes expressing innate-like T cells in adult human peripheral blood.
Hyaluronic acid/CD44 interactions control CD8 T cell memory development to influenza virus infection. (P1450)
Authors: Carrette Florent , Mueller Erin , Bradley Linda 
Published: January 2023

Abstract
CD44 is upregulated upon T cell activation during an immune response and remains highly expressed on memory T cells, which contribute to protection against challenge infection. However, its role in CD8 T cell response during infection is not well understood. Its main ligand is hyaluronic acid (HA), a glycosaminoglycan component of the extracellular matrix. In the steady state, HA exists at high molecular weight. Upon local inflammation, it is transiently broken down to low molecular weight forms. During influenza infection, we found that CD44-/- CD8 T cells accumulate normally during the expansion phase, but have an intrinsic defect in becoming memory cells. Furthermore, upon reinfection, the few CD44-/- memory CD8 T cells expand less than WT cells. CD44/HA binding is transiently induced in activated T cells, and we show that this interaction is crucial for effector CD8 T cell accumulation during infection. In addition, treatment of infected mice with IRAWB14, an agonist antibody promoting HA/CD44 binding, increased the accumulation of effector CD8 T cells. Correlating with an important role for low molecular weight HA, we found that IRAWB14 treatment is beneficial only if administered during the first phase of the infection, when low molecular weight HA is produced. Our data reveal that HA/CD44 interaction is an early essential and major regulator of the CD8 T cell immune response that controls the development of memory to influenza infection.
Myeloid-derived suppressor cell subsets inhibit T- and B-cell responses in murine Retrovirus-induced immunodeficiency (P6179)
Authors: Green Kathy , Fu Whitney , Cook W. , Green William 
Published: January 2023

Abstract
Compared to tumor microenvironments, myeloid-derived suppressor cells (MDSCs) have been less well studied in infectious diseases, particularly for retroviruses inducing immunodeficiency. We have found the development of a large population of immunosuppressive MDSCs after LP-BM5 retrovirus infection which causes murine acquired immunodeficiency. These MDSCs express a cell-surface marker signature (CD11b+Gr-1+Ly6C+) and inhibit not only T-cell, but B-cell, responsiveness by a substantially iNOS-dependent mechanism. MDSC immunosuppressiveness parallels the extent of disease in LP-BM5-infected w.t. vs. k.o. mice, differentially susceptible to disease. Retroviral load indicate that the suppressive Ly6C+CD11b+MDSC subset is LP-BM5 positive, although significantly lower than non-fractionated splenocytes from infected mice. Further fractionation of the MDSCs by FACS indicated, whereas all four subsets defined by Ly6C versus CD11b expression suppressed B-cell responses, only the Ly6Cbright CD11b+ subset suppressed T-cells, indicating distinct versus overlapping targeting of the two adaptive immune arms. These results, including the strong, direct MDSC inhibition of B-cell responsiveness, are novel for murine retrovirus-induced immunosuppression, and, as the total MDSC suppressive function mirrors that of LP-BM5-induced disease, support a pathogenic effector role for these retrovirus-induced MDSCs.
Identification of human endogenous retrovirus (HERV-K(HML-2))-specific mucosal CD4+ T cell responses in HIV-1-exposed, seronegative individuals (P6195)
Authors: SenGupta Devi , Ribeiro Susan , Michaud Henri-Alexandre , Loh Liyen , Tandon Ravi , Jones R. , Garrison Keith , York Vanessa , Cunha-Neto Edecio , Ostrowski Mario , Pilcher Christopher , Hecht Frederick , Martin Jeff , Deeks Steven , Hunt Peter , Nixon Douglas 
Published: January 2023

Abstract
The transcriptional silence of human endogenous retroviruses (HERV) can be disrupted in HIV-1 infection. We have reported that the strength of the HERV-specific CD8+ T cell response predicts lower HIV-1 viral load in untreated adults. To determine whether HERV-K immunity plays a role in inhibiting HIV-1 replication at a major site of transmission and CD4+ T cell depletion, we assessed these responses in gut-associated lymphoid tissue (GALT) from rectosigmoid biopsies and blood of HIV-1 exposed, seronegative (HESN) individuals (n=6) by flow cytometry. CMV pp65- and HIV-1 Gag-specific T cells were also measured, and all responses were compared with peripheral antigen-specific responses in uninfected, low-risk controls (n=11). With the exception of stronger CMV-specific CD8+ T cell responses in the HESN group (p=0.024), there were no significant differences between the magnitudes of peripheral antigen-specific T cell responses in the HESN vs. controls. However, HESN subjects had remarkably robust mucosal HIV-1- (median %CD4+cytokine+cells=2.67) and HERV-specific (median %CD4+cytokine+cells=3.41) CD4+ responses, which were much stronger than the corresponding PBMC responses (p=0.0079 and p&lt;0.0001, respectively). These findings suggest that the GALT is an important site of HERV-K expression and immunity in individuals exposed to HIV-1, and should be further investigated in the context of novel vaccine strategies that target conserved antigens such as HERV.
Exploitation of cross-reactive CTL “help” as a potential immune escape strategy for HIV-1 (P6201)
Authors: Mailliard Robbie , Smith Kellie , Fecek Ronald , Rappocciolo Giovanna , Watkins Simon , Mullins James , Rinaldo Charles 
Published: January 2023

Abstract
The ability of HIV-1 to rapidly accumulate mutations provides the virus with an effective means of escaping CD8+ cytotoxic T lymphocyte (CTL) responses. Here we describe how subtle alterations in CTL epitopes expressed by naturally occurring HIV-1 variants can result in an incomplete escape from CTL recognition, providing the virus with a selective advantage. Rather than paralyzing the CTL response, these epitope modifications are capable of “baiting” pre-existing cross-reactive CTL to partially respond by producing pro-inflammatory cytokines in the absence of target killing. Importantly, instead of dampening the immune response through CTL elimination of variant antigen-expressing immature dendritic cells (iDC), a positive CTL-to-DC immune feedback loop dominates whereby iDC differentiate into pro-inflammatory mature DC that have a superior capacity to mediate T cell trans-infection. This discordant induction of CTL “helper” activity in the absence of killing likely contributes to the chronic immune activation associated with HIV-1 infection, and can be utilized by HIV-1 to promote viral dissemination and persistence. Our findings highlight the need to address the detrimental potential of eliciting dysfunctional cross-reactive memory CTL responses when designing and implementing anti-HIV-1 immunotherapies.
Shp1 regulates T cell homeostasis by antagonizing IL-4 signalling (P1312)
Authors: Johnson Dylan , Pao Lily , Dhanji Salim , Murakami Kiichi , Neel Ben , Ohashi Pam 
Published: January 2023

Abstract
The tyrosine phosphatase Shp1 is expressed ubiquitously in hematopoietic cells and is generally viewed as a negative regulator. Null mutations in Ptpn6, which encodes Shp1, result in the motheaten phenotype, characterized by widespread inflammation that causes death by 3-4 weeks of age. Previous studies of motheaten mice identified Shp1 as a negative regulator of TCR signaling, but the severe inflammation in these mice could have confounded our understanding of Shp1 function in T cell biology. To define the T cell intrinsic role of Shp1, we have characterized T cell-specific conditional knockout mice. Surprisingly, we detect no changes in TCR responsiveness in Shp1-deficient thymocytes or peripheral T cells. Instead, T cell Shp1 KO mice are enriched for memory-phenotype T-cells that express elevated levels of CD44 in the periphery. In addition, activated Shp1-deficient CD4+ T cells skew to Th2 and produce elevated levels of IL-4. Following IL-4 stimulation, Stat 6 activation is sustained in Shp1 deficient T-cells, leading to enhanced IL-4 production. Elimination of IL-4, through in vivo administration of a neutralizing antibody or by crossing to IL-4 KO mice, results in marked reduction of the excessive memory-like population in T cell specific Shp1 KO mice. Therefore, Shp1 is an essential negative regulator of IL-4 signaling in and is critical for the maintainance of T cell homeostasis.
Remarkably intact antiviral CD8 T cell response despite the absence of caspase 8 apoptotic and RIP3 necrotic pathways (P1318)
Authors: Livingston-Rosanoff Devon , Daley-Bauer Lisa , Mocarski Edward 
Published: January 2023

Abstract
Two programmed cell death pathways, apoptosis and necrosis, impact T cell function in mice and humans. Germ line disruption of pro-apoptotic caspase 8 (Casp8) activity in T cells triggers receptor interacting protein kinase (RIP)3-dependent necrosis upon TCR stimulation. This absolute requirement for Casp8 repression of RIP3-dependent pathways overshadows potential contributions of extrinsic apoptosis to T cell expansion and contraction. Mice deficient in both Casp8 and RIP3 (Casp8-/-Rip3-/-) have an intact immune compartment and maintain naïve CD8 T cells comparable to Rip3-/- and WT controls. Based on CD44 expression, aging mice show evidence of CD8 T cell proliferation and lymphadenopathy. Despite this, CD8 T cells in Casp8-/-Rip3-/- mice proliferate normally in response to TCR stimulation. Upon infection with murine CMV, Ag-specific CD8 T cells from Casp8-/-Rip3-/- mice expand, produce cytokines, kill cells expressing viral peptide, and control infection similarly to controls. Memory CD8 T cells develop in Casp8-/-Rip3-/- mice with appropriate KLRG1 and CD127 expression. These memory cells expand in response to and protect from secondary challenge. Additionally, memory inflation, a characteristic of the response to murine CMV, is preserved. Thus, when RIP3 pathways are eliminated, Casp8 restricts homeostatic lymphoproliferation but plays no direct role in the CD8 T cell response to infection.