bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bovine γδ T cell response in foot-and-mouth disease virus infection (FMDV) (81.12)
Authors: Toka Felix N. , Golde William T. 
Published: January 2023

Abstract
In cattle, ?d T cells are a major population of the peripheral blood T cells but there is no precise description of their role in viral infections. We examined the phenotype and function of bovine ?d T cells during infection with FMDV. The early phase of infection was examined to test for a possible role for ?d T cells in innate responses against FMDV. Gamma delta T cells were sorted from PBMC of naïve or FMDV infected Holstein calves. The cells from naive animals highly expressed CD62 and CD45RO and about 50% expressed CD25, but not CD335. Gamma delta T cells did not produce IFNγ and no lytic activity could be demonstrated against a tumor cell target in vitro, although a very low level of perforin was detected. Cells from infected animals had phenotypic alterations on γd T cells between 2 and 6 days post infection (dpi). Expression of CD62 and CD45RO was down regulated and CD25 expression moderately increased. Unexpectedly, CD13 was expressed on days 2 and 3 after infection and were cytolytic against K562 cells. In addition, γδ cells isolated on these days expressed CD335, perforin and produced IFNγ. However, the isolated γd T cells produced less IFNγ and expressed less perforin compared to γd T cells assayed from non-sorted PBMC, indicating that the function of γd T cells may depend on factors derived from other cells. Overall, bovine γd T cells are activated upon infection with FMDV and adopt NK cell phenotypical and functional properties. Therefore, bovine γd T cells may likely participate in the innate response to infection with FMDV and targeting activation of γδ T cells could lead to rapid protection against FMDV infection.
Immunological animal models for the immunotherapy against Alzheimer’s disease

(81.13)
Authors: Vasilevko Vitaly , Head Elizabeth , Lemere Cynthia A. , Cribbs David H. 
Published: January 2023

Abstract
The pioneering work by Dale Schenk established that antibodies specific for the beta-amyloid (Aβ) peptide could reduce the level of Aß pathology in the brains of transgenic mouse model of Alzheimer's disease (AD), overexpressing a human mutant form of the amyloid precursor protein (APP). Unfortunately, the first immunotherapy clinical trial in AD patients, the AN1792, was halted due to meningoencephalitis in a subset of the patients that received the anti-Aβ vaccine. Efforts to develop next generation vaccines are now being pursued by various groups to eliminate or reduce the potential for adverse outcomes in patients.
To further explore the diversity of immune responses by different mammal species to Aß1-42 immunization and to choose the adequate immunological animal model we immunized several strains of mice, as well as rats, guinea pigs, rabbits, and dogs with the AN-1792 vaccine.
We found that the dominant anti-Aß B-cell epitope in mice, rats and guinea pigs is located in an internal sequence of Aß1-42, and serum from these species recognizes APP on a Western blot. Conversely, anti-Aβ antibodies from monkeys, canines and rabbits all closely resembled the reported immune response in humans by recognizing only the free N-terminus of Aß1-42, and did not recognize APP by Western blot.
Thus, careful selection of animal models for testing new vaccine candidates may facilitate effective translation to human clinical trials.
Support by NIH grants RO-1 AG20241, AG-00538, P50 AG16573 to DHC, AG20242 to EH
Serological analysis of equine antibody responses to the facultative intracellular bacteria Corynebacterium pseudotuberculosis (81.14)
Authors: Abdel-Massih Dina , Valle Luca , Bucknam Alexis , Spier Sharon , Pollock Roberta 
Published: January 2023

Abstract
Corynebacterium pseudotuberculosis is a gram positive facultative intracellular bacteria that causes pigeon fever or dryland distemper in horses. Most infected horses develop large pus-filled external abscesses, which resolve with a low mortality rate. Some infected horses develop internal abscesses, and about 40% of these animals die. Our hypothesis is that the TH1 toTH2 balance determines the form of the disease: TH1 dominance leads to external abscesses and TH2 dominance leads to internal abscesses. We developed an ELISA that measures the antibody response to phospholipase D (PLD), the major antigen and exotoxin of the bacteria, and screened 50 infected and uninfected horses. Current diagnostic criteria state that horses with internal abscesses have high level of antibodies to PLD and horses with external abscesses have low antibody titers. Our results show that while most horses with internal abscesses show high antibody responses to PLD, many horses with external abscesses and some uninfected horses also have high titers to PLD. The class and subclass of anti-PLD antibodies are being measured to test whether TH1 or TH2 induced antibodies predominate in horses with different forms of the disease.
Is IgT the evolutionary equivalent of IgA? Insights into its structure and function (81.21)
Authors: Sunyer Oriol , Zhang Yong-An , Li Jun , Parra David , LaPatra Scott E. 
Published: January 2023

Abstract
From an evolutionary perspective, immunoglobulins emerged for the first time in fish. Teleost fish are known to contain at least three immunoglobulin (Ig) isotypes, IgM, IgD and the recently discovered IgZ/IgT. Thus far nothing is known about the protein structure, function and distribution of IgZ/IgT. We have raised monoclonal antibodies against IgT that have enabled us to purify it from trout plasma. Our analysis show that IgT is a 180 kDa monomeric Ig and represents the first monomeric immunoglobulin to be shown in teleost fish. Thus far, IgM is the only known teleost fish Ig involved in eliciting antigen-specific immune responses in teleost fish. However, here we present for the first time exciting data showing that rainbow trout produces IgT-specific responses upon antigenic stimulation. In addition we have identified a unique B cell subset expressing exclusively surface IgT. Importantly, the distribution of IgT+ B cells is predominant in the fish mucosal surfaces, suggesting a possible role of IgT in mucosal immunity.
IgD+ cell populations in channel catfish, Ictalurus punctatus (81.8)
Authors: Edholm Eva-Stina I , Stafford James , Sahoo Manoranjan , Bengtén Eva , Miller Norman , Wilson Melanie 
Published: January 2023

Abstract
Only two immunoglobulin (Ig) molecules, IgM and IgD have been identified in the channel catfish. While IgM has been extensively studied and in many aspects resembles mammalian IgM, catfish IgD is quite different. It is a chimeric molecule consisting of a rearranged VDJ region spliced to the Cμ1 domain, followed by seven Cδ domains and either a transmembrane or secreted tail. Through the use of anti-IgM and anti-IgD monoclonal antibodies three different B cell populations were identified that differentially express IgM and IgD; IgM+/IgD-, IgM+/IgD+ and IgM-/IgD+. PCR and RACE protocols amplified appropriate Ig rearranged message from these sorted populations indicating that they contained functional B cells. Furthermore, co-immunoprecipitation, Western blot analyses, and RT-PCR showed that IgD in the IgM-/IgD+ sorted cell population preferentially associates with the catfish Ig light (L) chain isotype sigma (IgL σ?. In contrast, the IgM+/IgD-, IgM+/IgD+ B cell populations express all four of the catfish IgL isotypes, IgLσ, IgLλ??and the IgL¿? which includes F and G IgL chains. In addition a third IgD+ cell population was identified consisting of IgM-/IgD+ granular-like cells of unknown origin, which do not express IgD message, and thus appear to be armed with exogenous IgD via a putative IgD binding receptor.
Supported by NIH grant R01 AI19530 and UMMC IRSP 59908.
TSLP and IL-7 use two different mechanisms in regulating human CD4+ T cell homeostasis (82.1)
Authors: Lu Ning , Wang Yui-Hsi , Liu Yong-Jun 
Published: January 2023

Abstract
Homeostatic proliferation of CD4+ T cells depends on both self-peptide-MHC ligands and cytokines such as interleukin 7 (IL-7) and Thymic Stromal Lymphopoietin (TSLP). Although it is well established that IL-7 directly acts on CD4+ T cells, data on whether TSLP directly induce human CD4+ T cell proliferation and TH2 differentiation are conflicting. We report here that resting and activated CD4+ T cells express high levels of IL-7 receptors, but very low levels of TSLP receptor when compared with that expressed by myeloid dendritic cells (mDC). While IL-7 induce strong STAT1, 3 and 5 activation and promote the proliferation of naïve CD4+ T cells in the presence of anti-CD3 and anti-CD28, TSLP only induce a weak STAT5 activation which is associated with the marginally improved cell survival, but fail to induce CD4+ T cell proliferation and TH2 differentiation. The effect of TSLP on enhancing human T cell proliferation could be observed only when sorted naïve CD4+ T cells were cultured with contaminated mDCs at as low as 0.5% in culture. TSLP could only induce purified naïve CD4+ T cells to differentiate into TH2 cells in the presence allogeneic mDCs. This study demonstrates that IL-7 and TSLP use different mechanisms in regulating human CD4+ T cell homeostasis and underscores the importance of cell purity in immunology research.
Key words: interleukin 7, Thymic Stromal Lymphopoietin, T cell homeostasis, proliferation, survival
Cytomegalovirus (CMV) and human longevity: lessons from long-lived families (82.5)
Authors: Pawelec Graham , Maier Andrea B , Karin Haehnel , Westendorp Rudi JG , Derhovanessian Evelyna 
Published: January 2023

Abstract
Seropositivity for Cytomegalovirus (CMV) is one of the parameters comprising the "immune risk profile" (IRP) predicting mortality in the very elderly. However, as many centenarians are CMV-seropositive (CMV+), not infection per se, but the way in which the immune system controls the virus, might be important in ensuring longevity. To analyze this, we have investigated the CMV prevalence of individuals with 30% decreased mortality risk from long-lived families (offspring, n=200) and their partners as controls (n=200). 10-colour flow cytometry was used to determine the frequency of different adaptive and innate immune subsets in 100 offspring and 100 partners. CMV-seroprevalence was significantly less frequent in offspring, despite many sharing their daily living with an infected partner. The expected highly significant age-associated decrease in naïve T-cells and accumulation of late-differentiated memory T-cells in CMV+ individuals was confirmed only in controls whereas CMV+ and CMV-negative offspring showed similar immune profiles. Our data suggest that individuals genetically enriched for longevity are more resistant to becoming infected with CMV. Furthermore, even when they are infected, they seem to be less susceptible to CMV-driven changes to the immune system. We feel that these phenomena are likely to be related, perhaps causally.
This work was supported by EU 7FP LifeSpan (LSHG-CT-2007-036894), DFG-SFB685-B4 and DFG-PA 361-11/1
IL-2 signals are required for complete effector differentiation of CD8+ T cells upon acute infection in vivo (83.17)
Authors: Sacks Jilian A. , Bevan Michael J. 
Published: January 2023

Abstract
CD8+ T cells are critical for protection against viral and intracellular bacterial infections. They are characterized by their ability to acquire cytolytic activity to lyse infected target cells. This effector stage is associated with the expression of a variety of intracellular and cell surface markers. Here, we examined the role of direct signaling by the cytokine IL-2 on the acquisition of CD8+ T cell effector functions. IL-2 signals via its heterotrimeric high-affinity receptor composed of the IL-2Rα-chain (CD25), β-chain (CD122) and common γ-chain (CD132). Previous work from our lab and others has shown that direct IL-2 signaling on CD8+ T cells is imperative for their differentiation into memory cells capable of secondary expansion. Using a mixed bone marrow chimeric approach in which wildtype (WT) and CD25 knockout (KO) cells are responding in the same environment we now demonstrate that KO CD8+ T cells are defective in effector differentiation following primary acute infection. CD25 KO effectors show decreased lytic activity and expression of effector-associated proteins and transcription factors, such as Granzyme B and T-bet. In addition, these cells show increased expression of naïve/memory-associated factors, such as Bcl2, Eomesodermin and IL-2 production, despite their inability to expand upon rechallenge. Overall, we conclude that direct IL-2 signaling is required for complete CD8+ T cell effector differentiation following infection in vivo.
This work was supported by the Howard Hughes Medical Institute and the National Institutes of Health Grant AI-19335 (to M.J.B.)
Lack of LFA1 mediated signals promotes generation of memory precursor effector CD8 T cells during LCMV infection (83.19)
Authors: Peixoto Antonio , Iannacone Matteo , Alvarez David , Buchanan Ian , Flynn Michael , von Andrian Uli 
Published: January 2023

Abstract
Multiphoton intravital microscopy (MP-IVM) studies have revealed that T cell priming encompasses a prolonged phase of stable interactions between T cell and Dendritic cells (DCs). Although believed to promote T cell activation, the role of prolonged T-DC interactions remains poorly understood. Here we dissect the contribution of LFA1 mediated adhesion/signaling in two settings: in mediating P14 T cell interactions with GP33-39 peptide pulsed DCs and modulating the differentiation of P14 T cells after an LCMV infection. First, we show that the lack of LFA1 on P14 T cells significantly decreases the T-DC interaction time measured by MP-IVM. Second adoptive transfer of physiological numbers of P14 LFA1 -/- T cells into WT recipients generated reduced effector cell numbers at day 8 after LCMV i.p. infection, when compared to P14 LFA1+/+ T cells. Moreover, P14 LFA1-/- T cells were poor cytokine producers and showed a significant increase in the frequency of IL7Rhigh KLRG1low memory precursor effector cells. In summary, our results suggest that prolonged T-DC interactions mediated by LFA1 promote generation of short lived effector cells. In contrast, short lived T-DC interactions promote the generation of memory precursor effector cells.
Molecular signature of human virus specific effector CD8+ T cells (83.20)
Authors: Akondy Rama S , Miller Joseph D , Doho Gregory , Wu Hong , Zilliox Michael , de Rio Carlos , Mulligan Mark J , Edupuganti Srilatha , Haining W. Nicholas , Ahmed Rafi 
Published: January 2023

Abstract
Evaluation of the cellular immune response soon after an infection is difficult in humans. In consequence, most of our current understanding of the differentiation of an antiviral CD8+ T cell response derives from either total T cells or from cross sectional studies or from various persistent or recurring viral infections. Effective live viral vaccines like the 17D strain of yellow fever virus (YF-17D) model a primary acute viral infection and present an opportunity to study the attributes of an anti-viral CD8+ T cell response in humans. The activation markers HLA-DR and CD38 have been previously shown to identify effector CD8+ T cells after a primary vaccination (Miller et al, 2008). We use these markers to isolate YF-17D specific effectors from human vaccinees. This effector population is transient, appears only during an anti-viral response and contains mostly YF-17D specific CD8+ T cells. Gene chip analysis of these cells shows that effectors undergo dramatic reprogramming as evidenced by changes in the number of genes (~4000) and their expression (effector / naïve fold change from +100 to -26) when compared to naïve CD8+ T cells. This signature is distinct not only from naïve CD8+ T cells but also from the TCM, TEM, and TEMRA memory subsets. We also show that the effector gene expression profile is fairly conserved when compared to the mouse LCMV effectors. One of the many uses of this signature is to understand and identify factors involved in naïve to effector cell differentiation.
This research was supported by NIH/NIAID (U19 AI057266).
The tyrosine kinase PYK2 integrates TCR and LFA-1 signaling in CD8 T cells to promote effector versus memory fate (83.21)
Authors: Beinke Soren , Matloubian Mehrdad , Schlessinger Joseph , Weiss Arthur 
Published: January 2023

Abstract
Focal adhesion kinase regulates integrin-mediated interactions of non-hematopoietic cells. In T cells, the homologous proline-rich kinase 2 (PYK2) is activated by the T cell antigen receptor and the integrin LFA-1 but its function is not well understood. Studying T cells from PYK2 knockout mice, we have demonstrated that PYK2 is essential for LFA-1 mediated T cell polarity and activation of CD8 T cells by synergistic TCR / LFA-1 stimulation or antigen presenting cells in vitro. During the acute response to lymphochoriomeningitis virus (LCMV) infection in vivo PYK2-deficient CD8 T cells are impaired in their expansion and differentiation into short-lived effector cells but generate normal numbers of memory precursor cells. Interestingly, the LCMV specific CD8 T cell memory population that is maintained long-term after LCMV infection is increased in PYK2 knockout mice. These data indicate that PYK2 deficiency results in an alteration in CD8 T cell fate during priming leading to a loss of effector but gain of memory functions. Therefore, PYK2-mediated T cell polarity may be an important determinant of CD8 T cell fate.
Visualizing interactions of antigen, B cells and FDC in vitro (84.23)
Authors: Kim Young-A , Carroll Michael C 
Published: January 2023

Abstract
Follicular dendritic cells (FDC), which reside in the primary B cell follicles and germinal centers of secondary lymphoid organs, can trap and retain antigens (Ag) in the form of immune complexes (IC) through Fc and complement receptors. Ag presentation by FDC plays an important role in the positive selection of high-affinity B cells and possibly maintenance of memory B cells. Recent studies reveal that B cells transport IC from the splenic marginal zone and subcapsular sinus in draning lymph node to FDC via complement receptor (CR, CD21/35). How Ag is transferred to FDC and subsequently presented to cognate B cells is not clear. To investigate interactions between Ag, B cells, and FDC in vitro, spinning disk confocal microscopy was used. We found that IC taken up via CR on B cells form clusters on the cell surface and this may enhance transfer to CR on FDC. Moreover clustering of IC and CR is independent of CD19 based on analysis of B cells prepared from mice bearing a mutant CR.
Naive B cells participate in secondary antibody response via immune complex mediated activation (84.6)
Authors: Goins Chelsey L , Chappell Craig P , Murthy Shashidhara , Selvaraj Periasamy , Jacob Joshy 
Published: January 2023

Abstract
The adaptive immune system confers survival advantage to the host by its inherent ability to respond to a plethora of pathogens and its ability to never forget an antigenic insult. In the case of humoral immune responses, repeat antigenic exposure leads to a secondary antibody response that is 2-3 orders of magnitude greater than the primary. This increased efficacy is due to the production of amplified levels of antigen-specific antibody, as well as the accelerated kinetics of their production. Current dogma holds that this response results from activation of memory B cells, which are formed following primary exposure and can rapidly produce large quantities of specific antibody upon secondary exposure. Our research, however, suggest that memory B cells may not be the chief source of antibody during the secondary response. Using a hapten model system we have shown that the phenomena associated with secondary responses - increased antibody levels and accelerated kinetics of antibody production - can be recapitulated by primary immunization with immune complexes. This suggests that immune complexes are able to activate antigen-inexperienced naive B cells in such a manner that their response mirrors a secondary response. Additionally we have found that blocking the Fc receptor binding activity of immune complexes inhibits the secondary antibody response. We propose that immune complexes are formed upon secondary antigen exposure, and that these complexes enhance the secondary antibody response through naive B cell activation.
Proliferative and phenotypic characterization of human mesenchymal stem cells by flow cytometry (84.7)
Authors: Bradford Jolene A , Clarke Scott T , Boucher Shayne , Vemuri Mohan 
Published: January 2023

Abstract
Adult human mesenchymal stem cells (hMSCs) are rare fibroblast-like cells that can differentiate into numerous tissue types, such as bone, cartilage and fat. hMSCs can impact tumorigenesis and tumor progression, including lymphoid neoplasias. hMSCs have been defined as positive for CD73, CD90, CD105 and negative for CD14, CD19, CD34, CD45 and HLA-DR. Phenotypic and proliferation profiling of hMSC through multiple passages can reveal changes that are indicative of gradual lineage restriction. We characterized hMSC using flow cytometry and an eight-marker panel in combination with DNA content and cell proliferation analyses. Using two hMSC sources, adipocyte-derived (ADSC) and bone marrow-derived (BMSC) stem cells, lineage restriction was inferred from changes in marker expression and proliferation rate over multiple passages. Using XenoFree media, the proliferation rate for ADSC decreased at low passage number while BMSC maintained expected phenotypic and proliferation profiles over multiple passages. When a lipid supplement was added, ADSC maintained phenotypic and proliferation profiles similar to BMSC. Flow cytometry allows robust and rapid analysis of phenotypic and proliferative responses by hMSCs cultured under serum-free and/or xenofree conditions. This approach can have strong relevance for cell-based therapy and for studying interactions between normal stem cells and cancer.
Unique properties of CD4 T cells selected by MHC class II expressing thymocytes (85.1)
Authors: Chang Cheong-Hee , Sofi Hanief , King Phil , Schwartzberg Pam , Qiao Yu 
Published: January 2023

Abstract
We have demonstrated that MHC class II expressing thymocytes can efficiently mediate positive selection of CD4 T cells in mice. Human thymocytes express MHC class II and thymocyte-mediated CD4 T cells selection provides a mechanism for several documented observations made in humans that could not be explained otherwise. We named thymocyte-selected CD4 cells T-CD4 (Thymocyte-selected) and the other E-CD4 (Epithelial cell-selected) to reflect their selection pathway.
T-CD4 T cells are distinct and different from E-CD4 T cells by exhibiting the effector function similar to innate T cells. T-CD4 cells can produce both Th1 and Th2 cytokines simultaneously shortly after activation. Remarkably, Stat6 that is critical for Th2 cell differentiation is not required for T-CD4 T cells to produce Th2 cytokines. Interestingly, these characteristics are found in NKT cells that are also selected on thymocytes. Consistent with these observations, development of T-CD4 T cells require SLAM/SAP signal that is essential for NKT but not E-CD4 T cells. To understand the molecular mechanisms and signaling pathways that are involved in T-CD4 T cell generation, we studied the role of ITK and RasGAP. ITK deficient cells were selected more efficiently by thymocytes than thymic epithelial cells. In contrast, RasGAP plays a more important role in the generation of T-CD4 T cells than E-CD4 T cells. Therefore, E- and T-CD4 T cells require different signaling mechanisms for their optimum development.
The study was partly supported by NIH.