bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic diversity of the avian chB6 alloantigen (81.18)
Authors: Funk Phillip E , OLaughlin Peter J 
Published: January 2023

Abstract
Chickens are one of the classic models of vertebrate immunity. We have been interested in the role of the alloantigen chB6 (formerly called BU1) in the development of B cells within the bursa and have presented evidence that chB6 can trigger apoptosis. chB6 is an alloantigen and in the original report of its cloning three alleles were reported, chB6.1 in RPL line 6 flocks, chB6.2 in RPL line 7, and chB6.3 in Light Sussex birds. However, no further search for other chB6 alleles has been reported. Using the chicken EST database we have identified five potential new alleles of chB6, although some of these EST clones are not full length cDNAs.. We have resequenced these EST clones to confirm the base sequence and translation. These results suggest greater genetic diversity of the chB6 locus than previously appreciated. Furthermore, rt-PCR was used to clone the turkey homologue of chB6. The results presented here are the beginnings of a larger study to examine chB6 and can provide novel insights into the evolution of immune related genes in Aves. This work supported by a summer grant from the DePaul College of Liberal Arts and Sciences.
Genes encoding proteins of immunological interest in the Oryctolagus cuniculus (rabbit) whole genome sequences and ENCODE (81.19)
Authors: Mage Rose G. 
Published: January 2023

Abstract
Rabbits are a valuable resource for diagnostic and therapeutic antibodies, are becoming increasingly important for vaccine development and as animal models of human diseases. They remain a major source of polyclonal and monoclonal antibodies because unique characteristics of their immune system result in antibodies of high affinity and specificity. The whole genome shotgun (2x WGS) "unfinished Oryctolagus cuniculus database" had serious gaps, but assemblies of the 2x WGS sequence were useful for designing primers for PCR by predicting mRNA sequences and exon boundaries. Deeper 7x WGS coverage was completed in 2008 and assembly of a high quality draft rabbit genome sequence is nearing completion. The "Thorbecke Inbred Rabbit" chosen for sequencing at Broad Institute was less heterozygous than outbred NZW but the Trace Archive of Oryctolagus cuniculus (WGS) reveals heterozygosity at the immunoglobulin heavy chain locus. The ENCODE Project with ~ 1% of rabbit genomic sequence from a different animal has rabbit genes of immunological interest including a gene cluster syntenic with human and mouse containing IL13, IL3, IL4, IL5 and IRF1. Rabbit genome sequences can contribute comparative genomic data, reveal variants of genes of immunological interest, and genetic contributions to animal and human disease susceptibilities. This research was supported by the Intramural Research Program of the NIH, NIAID.
Cloning and functional characterization of a rainbow trout CD80/CD86 ortholog (81.22)
Authors: Zhang Yong-An , Hikima Jun-ichi , Li Jun , Sunyer J. Oriol 
Published: January 2023

Abstract
In mammals, interaction of CD28 with CD80 or CD86 molecules provides costimulatory signals for T cell activation. Such signals lead to increased gene and protein expression of IL-2 by activated T-cells. CD80 and CD86 have only been cloned in mammals and birds thus far, and their functional characterization is basically limited to their study in mammals. Thus, in the present study we show for the first time the cloning of a rainbow trout molecule (rtCD80/86) that shows a high degree of homology to CD80 and CD86 molecules. In addition, we have identified and cloned trout IL-2 and we have shown that recombinantly produced trout CD80/86 upregulates the expression of IL-2 in trout blood leukocytes. This finding indicates that this capacity to modulate IL-2 expression is a primordial function that has been conserved both in fish and mammalian CD80/CD86 molecules throughout evolutionary time.
Non-apoptotic caspase-8 activation balances T lymphocyte autophagy (82.14)
Authors: Bell Bryan D , Leverrier Sabrina , Weist Brian M , Walsh Craig M 
Published: January 2023

Abstract
Apoptosis and autophagy are critical mediators of a functional immune response. FADD and caspase-8 (casp8) were originally discovered to transduce apoptotic signals delivered through TNF family members. Paradoxically, lymphocytes lacking FADD or casp8 function have impaired clonal expansion following antigen receptor crosslinking and succumb to a caspase-independent cell death. We show that T cells lacking FADD or casp8 are subject to hyperactive autophagy. T cell autophagy induces casp8 activation through its interaction with FADD:Atg5:Atg12 complexes. Blockade of autophagic signaling with shRNA knockdown of the autophagy-dependent protein Atg7 leads to a rescue of T cells lacking FADD and casp8. Similarly, inhibition of RIPK1 kinase activity with necrostatin-1 completely restored T cell cycle and survival. We hypothesize that the non-apoptotic casp8 activity serves to dampen the autophagic response of proliferating T cells through direct cleavage of RIPK1 or the casp8 homolog, c-FLIP, which may secondarily inhibit RIPK1-dependent authophagic signaling. While rapidly dividing T cells require autophagy, this negative feedback loop can prevent hyperactive autophagy. Linking apoptotic proteins to this signaling paradigm may serve to prevent an inflammatory response driven by autophagic cell death in lymphocytes during an immune response. (Funded by NIH T32CA09054 to B.D.B. and R01AI63419 to C.M.W.)
Naturally occurring memory (CD44hi) CD4 T cell responses are differentially regulated by the expression of programmed death-1 receptor (82.4)
Authors: Suvas Susmit , Channappanavar Rudragouda , Twardy Brandon 
Published: January 2023

Abstract
CD4 T cells in unprimed mice can acquire CD44hi memory phenotype (MP) and the MP CD4 T cell subset become progressively more prominent with age. Although it is not clearly evident if MP CD4 T cells arise due to lymphopenia-induced proliferation or environmental antigen exposure, studies carried out in mice model suggest that naturally occurring MP CD4 T cells are hyporesponsive to both polyclonal and TCR mediated stimulus. In this report we determined that a large proportion of naturally occurring MP CD4 T cell pool in unprimed mice expressed multiple inhibitory receptor PD-1, ICOS and CTLA-4. Furthermore, inhibitory receptor expressing MP CD4 T cells become more prominent with advancing age. Our results showed that PD-1hi MP CD4 T cells isolated from aged mice were more susceptible to spontaneous apoptosis when compared with PD-1lo MP CD4 T cells. We also determined the differential expression of IFN-γ, IL-2 and IL-17 cytokines in PD-1+ versus PD-1- MP CD4 T cells isolated from unprimed young and old mice. Lastly, MP CD4 T cells purified from aged mice proliferated differentially to Con A stimulus depending on the expression of PD-1 receptor. Thus, we conclude that responses of naturally occurring MP CD4 T cells are differentially regulated by the expression of inhibitory PD-1 receptor.
Supported by the funds derived from American Federation for Aging Research (AFAR).
A high level of isoform V in the CD40 receptor composition leads to survival/proliferation signals in autoimmune Th40 cells (82.6)
Authors: Vaitaitis Gisela M , Wagner, Jr David H 
Published: January 2023

Abstract
CD40 - CD154 interactions are critical in autoimmunity. CD4loCD40+ T cells (Th40) are expanded in autoimmunity and are necessary and sufficient in transferring disease. The expansion, as well as disease onset, is prevented by blocking CD154. Autoimmune Th40 constantly recruit high levels of CD40 and TRAF2 to the raft microdomain for signaling. CD40 stimulation further increases those levels and induces high levels of Bcl-XL and cFLIPp43 leading to survival and proliferation. In non-autoimmune Th40, only low levels of CD40 and TRAF2 are recruited to the raft even upon CD40 stimulation and this only induces Bcl-XL without an effect on survival and proliferation. There are five CD40 isoforms that multimerize to form a functional receptor in mice. We speculated that differing CD40 receptor composition could be responsible for the signaling differences. Here we show that autoimmune Th40 have a high ratio of isoform V to isoform I while it is drastically lower in non-autoimmune Th40. Th40 from autoimmune mice that had been treated to block CD154 demonstrated a ratio similar to that of non-autoimmune Th40 suggesting that the CD40 receptor composition depends on the availability of CD154 and that a receptor predominantly composed of isoform V is directly related to the ability to induce proliferation. Interestingly, when non-autoimmune mice were injected with agonistic CD40 antibodies the Th40 population expanded and the CD40 isoform ratio changed to look like those in autoimmune animals. Therefore it is important to understand what conditions lead to the expression of one CD40 isoform over another and whether those conditions can be altered in autoimmunity.
MS4a4B: a novel regulator in T cell proliferation (82.9)
Authors: Xu Hui , Yan Yaping , Williams Mark S , Fowler Daniel H , Carey Gregory B , Zhang Guang-Xian , Rostami Abdolmohamad 
Published: January 2023

Abstract
MS4a4B is a novel member of the recently discovered MS4A gene family (Membrane-spanning 4-domain family, subfamily A). The most well-known members of MS4A gene family include CD20, FcεRIβ and HTm4. An increasing body of evidence has demonstrated roles of the MS4A proteins in cell function, particularly for CD20 and HTm4. CD20 is involved in cell cycle regulation and apoptosis in B cells. HTm4 has been found to regulate the cell cycle through the KAP-CDK2 cascade. To date, the function of MS4a4B is unknown. In a screen for genes potentially involved in T cell development we cloned MS4a4B. Our data show that MS4a4B was expressed in primary T cells. The expression of MS4a4B in T cells was enhanced upon T cell activation. Interestingly, we observed a loss of MS4a4B expression in all the malignant T cells we have tested to date, including thymoma cells and T hybridoma. To determine the role of MS4a4B, we expressed MS4a4B in T cells by MS4a4B-expressing-vectors. Over-expression of MS4a4B reduced proliferation of T cells. Similarly, forced-expression of MS4a4B in EL4 cells, a thymoma cell line, by viral vector also inhibited the proliferation of the thymoma cells. Our results suggest that MS4a4B plays a regulatory role in T cell proliferation.
Supported by American Heart Association grant AHA-0830072N (to H.X)
Differential localization of effector and memory T cell subsets (83.16)
Authors: Jung Yong Woo , Kaech Susan M 
Published: January 2023

Abstract
During viral infections, it is not well defined where within tissues effector and memory CD8 T cells form and persist. Our recent findings show that two subsets of effector CD8 T cells that have distinct cell fates are formed during acute infection - the KLRG1hi IL-7Rlo short-lived effector cells (SLECs) and the KLRG1lo IL-7Rhi memory precursor effector cells (MPECs). Most of the SLECs undergo apoptosis after infection whereas most MPECs survive and become long-lived memory T cells. Here, we show that MPECs and SLECs are differentially localized within the spleen during LCMV infection. Using immunofluorescence microscopy, we demonstrate that the majority of MPECs were found in the T cell zone, while SLECs were exclusively localized in the red pulp during the course of an immune response to LCMV infection. At memory time points, only T cells with an MPEC phenotype were found in the T cell zone. MPECs homed to the T cell zone using pertussis toxin-sensitive chemokine receptors, and appeared to contact with gp38+ stromal cells, which produce chemokines CCL19 and CCL21 and the T cell survival cytokine IL-7. Employing a transwell migration assay, we found that MPECs showed higher chemotactic ability toward CCL19 than SLECs. Together, our data suggest that the preferential survival of the MPECs and the memory T cells may be tightly linked to their localization in the T cell zone and the interaction with IL-7-producing stromal cells.
Triglyceride lipids can enhance the cytotoxicity of induced cytotoxic T lymphocytes (CTLs) (83.8)
Authors: Hudig Dorothy , Alves Bryce N , Marshall Kristen , Tamang David L , Leong Jeffrey , Redelman Doug , Elliott Viki , Lowe Mark E 
Published: January 2023

Abstract
IL-4 induces pancreatic lipase related protein 2 (PLRP2) in cytotoxic T lymphocytes (CTLs). Because PLRP2 in semen mediates lipid-dependent toxicity to sperm, we questioned whether CTL-derived PLRP2 could support similar cytotoxicity towards tumor cells. First we tested recombinant PLRP2. Microgram/ml concentrations were toxic to P815 cells in 48 hr assays when lipid and co-lipase were present. Next we found that CTLs secrete triglyceride lipase but that most IL-2 or IL-4 induced CTLs were unable to mediate lipid-dependent cytotoxicity. A single, exceptional lot of IL-4 reproducibly induced lipid-dependent cytotoxicity that was also perforin-independent. In efforts to induce the lipid-dependent CTL killing again, attempts were made to block type 1-polarizing cytokines, including biasing the T cells cultures with more IL-4 or with IL-12 blocking antibodies, and using T cells without IFN-ã receptors. These attempts were unsuccessful at inducing triglyceride-enhanced cytotoxicity. The CTLs induced with IL-4 consistently had mRNA for PLRP2 but lacked mRNA for co-lipase. Therefore, we added exogenous co-lipase to the cytotoxicity assays. Cytotoxicity was unaltered. We conclude (1) that lipid-dependent cytotoxicity by PLRP needs co-lipase and (2) that more than PLRP2 is required for lipid-dependent cytotoxicity by CTLs. Supported by NIH R01CA38942 and T32CA09563.
The C3d/Epstein-Barr virus receptor (gp140, CR2, CD21, EBV/C3dR) triggers distinct signaling pathways, independently of CD19 or BCR, in human B lymphocytes. (84.1)
Authors: FRADE Raymond 
Published: January 2023

Abstract
We originally isolated gp140, the receptor of human C3 (the third component of complement) from Raji, a human B lymphoma cell line (1981). gp140 is the C3d receptor (1983, 1985a) and also the Epstein-Barr virus receptor (1985b). Activated EBV/C3dR regulates B lymphocyte proliferation (1985c). EBV interaction with EBV/C3dR is the first step of B lymphocyte transformation (1985b). Activated EBV/C3dR interacts through its intracytoplasmic domain, with the p53 oncoprotein (1989, 1992, 1995) or a p68 Cabp (1991, 1992, 1995). We identified the two first signaling pathways specifically triggered by activated EBV/C3dR. The first pathway, independent of CD19 and BCR activation, is characterized by: 1) activation of pp60src kinase to tyrosine phosphorylate nucleolin; 2) tyrosine phosphorylated nucleolin interacts with the SH2 domains of the p85 subunit of PI-3 kinase, activating this latter; 3) activated PI 3-kinase recrutes the AKT-GSK3 pathway (1999, 2001, 2003). The second pathway is characterized by: 1) Cbl phosphorylation; 2) interactions of phosphorylated Cbl with Crk-L, Syk and the p85 subunit of PI-3-kinase; 3) dissociation of phosphorylated Cbl from Vav (2006). This dissociation, opposed to the Cbl-Vav association triggered by CD19 or BCR, emphasizes the specificity of EBV/C3dR signaling pathways. We herein identified the functional relationship between these two pathways.
Cyclooxygenase-2 is Essential for the Optimal Differentiation of Human Antibody Secreting Cells: Implications for Vaccination (84.11)
Authors: Phipps Richard P , Bernard Matthew P 
Published: January 2023

Abstract
Generation of optimal humoral immunity in response to vaccination is essential in order to protect the public from potentially devastating infectious agents. Cyclooxygenase inhibitors are amongst the most widely used and commonly prescribed medications. However, relatively little is understood about their influence on human immune responses. Herein, we report that non-steroidal anti-inflammatory drugs (NSAIDs) and small molecule Cox-2 selective inhibitors attenuated human B cell immunoglobulin production in a Cox-2-dependent manner. We further demonstrated that the Cox-2 selective inhibitors SC-58125 and NS-398 non-selectively blunt the production of human antibody isotypes including IgM, IgG1, IgG2, IgG3 and IgG4. This correlated with a significant reduction in the generation of CD38+ IgM+ and CD38+IgG+ antibody secreting plasma cell precursors. Interestingly, we discovered that inhibition of Cox-2 activity with SC-58125 severely reduced the mRNA and protein levels of the essential plasma cell transcription factors, Blimp-1 and Xbp-1 in normal human B cells. These new results demonstrate an essential role for Cox-2 in the terminal differentiation of human B lymphocytes to antibody secreting cells. Our findings suggest that the use of drugs that attenuate Cox-2 activity can reduce the generation of plasma cells and ultimately optimal antibody responses to vaccines and pathogenic infections.
This research was supported by DE011390, ES01247, AI071064 and T32-DE007202.
Molecular mechanism of allelic exclusion of TCR alpha chains (84.2)
Authors: Rybakin Vasily , Gascoigne Nicholas R.J. 
Published: January 2023

Abstract
Allelic exclusion is a mechanism whereby a product of single allele is selected for expression. In case of the T cell receptor, allelic exclusion takes place differently for TCRa and TCRb chains. For the TCRb chain, a successfully completed in-frame rearrangement of one locus effectively inhibits the rearrangement of the second locus. This inhibition is achieved as a result of signaling originated from a successfully formed dimer of the b chain with pre-Ta.
In contrast, both TCRa alleles are rearranged, often multiple times, until the positive selection stage, when a single a chain in conjunction with a fixed b chain allows the thymocyte to differentiate. Majority of immature thymocytes express more than one a chain on the cell surface, while after positive selection only one chain is expressed.
We developed and experimental system allowing to directly assess the fate of each of two specific a chains by flow cytometry and microscopy. Our studies are aimed at the better characterization of posttranslational modifications and signaling events leading to the selection of a single TCRa chain expressed at the cell surface.
Stim1 sets a threshold for activation of a pro-apoptotic Erk pathway in B cells (84.21)
Authors: Limnander Andre , Weiss Arthur 
Published: January 2023

Abstract
Developing B cells differ from mature B cells in signaling downstream of the B cell receptor (BCR), and these differences play a crucial role in repertoire selection. While BCR crosslinking in mature B cells leads to proliferation and activation, in immature B cells it triggers apoptosis. BCR-induced Ca2+ entry is higher and prolonged in immature B cells with respect to mature B cells. While it is known that differences in Ca2+ signals play a role in the differing BCR responses during B cell development, the exact signaling pathways involved in the apoptosis vs. proliferation decision remain elusive. Stim1 is a Ca2+ sensor that is required for gating of the CRAC channels, and its expression is transiently increased during B cell development. We demonstrate that increasing Stim1 expression is sufficient to augment the amplitude and duration of Ca2+ entry in B cells, and consequently sensitizes B cells to antigen-induced apoptosis. Increased intracellular Ca2+ activates a pro-apoptotic, Ca2+-dependent pathway to Erk, and the biochemical requirements for Ca2+-dependent Erk activation differ from those of diacyl glycerol (DAG)-mediated Erk activation. In immature B cells, increases in Ca2+ entry that outlast increases in DAG levels may lead to activation of pro-apoptotic, Ca2+-dependent ERK signals that override DAG-mediated proliferative signals, thereby triggering negative selection.
The class II Histone deacetylase 7 controls Interleukin 2 receptor expression and proliferation of primary cytotoxic T cells (84.8)
Authors: Navarro Maria N , Goebel Jurgen , Feijoo-Carnero Carmen , Cantrell Doreen A 
Published: January 2023

Abstract
Regulation of chromatin accessibility via class II histone deacetylases is a critical mechanism controlling gene expression. The paradigm for class II HDAC regulation is that in quiescent lymphocytes these molecules localise to the nucleus and form repressive complexes on chromatin. Antigen receptor activation of Protein Kinase D induces phosphorylation and nuclear export of HDACs thereby relieving their repressive actions on chromatin and gene expression. In this context, the present study has examined the regulation and function the class II histone deacetylase 7 in effector cytotoxic T cells (CTLs). This HDAC has been shown previously to function as a signal dependent repressor of gene transcription during T cell development in the thymus. We now show that HDAC7 is a critical regulator of Interleukin 2 receptor expression and proliferation in primary CTL. Strikingly, there is constitutive and sustained phosphorylation and export of HDAC7 from the nucleus to the cytosol in CTLs. The cytosolic localisation of HDAC7 is determined by the phosphorylation of key serine residues in the molecule S156, S322, S457 and by a balance of src kinase and diacylglycerol signalling pathways that increase its nuclear export and block its nuclear import. An HDAC7 mutant (S156A, S322A, S457A) that cannot be phosphorylated is thus maintained in the nucleus and prevents expression of the Interleukin2 (IL-2) receptor and accordingly inhibits CTL responses to IL-2. HDAC7 thus acts as a molecular switch to mediate IL-2 receptor expression and cellular responsiveness to IL-2 in primary T cells.
IL-12 enhances generation of CD25+ cells from common lymphoid progenitors in OP9-DL1 co-cultures. (85.14)
Authors: Van De Wiele C. Justin , Tan Chibing , Davis Brenda K. , Teague T. Kent 
Published: January 2023

Abstract
Efficient in vitro production of T cells from bone marrow precursors represents a major technical hurdle that must be overcome in order to fully realize the potential benefits of future tailored immunotherapies. We have utilized the OP9-DL1 system to determine whether interleukin-12 (IL-12) influences development of common lymphoid progenitors (CLPs) towards the T cell fate. Inclusion of 5 ng/ml recombinant mouse IL-12 in addition to standard levels of IL-7 (5 ng/ml) and Flt3L (5 ng/ml) doubled the number of recoverable viable cells after one week of culture in comparison to control cultures. As the cells differentiated to a DN3a-like stage (Lin-CD4-CD8-CD25+CD44-CD117-CD28lo)during the following two weeks of culture, the effectiveness of IL-12 gradually diminished. This was not completely unexpected as IL-12 response assays on developing thymocytes demonstrated induction of STAT4 phosphorylation only within the very earliest DN1cKit+ and DN2 thymic subsets. The effectiveness of IL-12 in promoting production of bona fide T cell precursors was demonstrated by the observation of enhanced cell yields from IL-12 containing DN2/OP9-DL1 co-cultures. The IL-12 effect was titerable and was abrogated by genetic absence of the IL-12Rβ2, indicating a direct effect of IL-12 on the developing lymphoid cells.