bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acute myeloid leukemia transcription profile based on natural killer cell status at diagnosis correlates with clinical outcome (TUM10P.1047)
Authors: Toubert Antoine , Khaznadar Zena , Boissel Nicolas , Agaugue Sophie , Henry Guylaine , Cheok Meyling , Vignon Marguerite , Geromin Daniela , Cayuela Jean Michel , Lachuer Joel , Preudhomme Claude , Dombret Herve , Dulphy Nicolas 
Published: January 2023

Abstract
Acute myeloid leukemia (AML) is a heterogeneous group of malignancies sensitive to natural killer (NK) cell anti-tumor responses. However, NK cells are frequently defective in AML. Here, we found in an exploratory cohort (n = 46) that a different expression of activating receptors (NCR) on NK-cells identified a subgroup of patients with reduced expression of DNAM-1, NKG2D, NCRs and perforin especially in CD56bright NK-cells. Patients with a deficient NK-cell profile had a significantly higher risk of relapse (P = 0.03) independently of cytogenetic classification in multivariate analysis. We hypothesized that the transcription patterns in AML cells could give a clue on the NK/AML crosstalk. Analysis of the gene expression in AML blasts following classification according to their NK-cell status showed extensive differences in immune-related and oncogenic pathways. A favorable NK status was associated with pro-inflammatory AML transcription patterns whereas patients with defective NK cells showed a profound gene expression decrease in AML blasts for cytokine and chemokine signaling, antigen processing and adhesion molecule pathways. A set of 388 leukemic classifier genes defined in the exploratory cohort was independently validated in a multicentric cohort of 194 AML patients (ALFA-0701). In total, these data evidenced the prognostic value of NK-cell responses at diagnosis of AML and the relationships between NK-cells and AML independently of known cytogenetic status.
Surviving the odds: targeting PIM2 in plasma cell survival (TUM10P.1051)
Authors: Nair Jayakumar , Baldino Carmen , Caserta Justin , Carlson Louise , Fetterly Gerald , Lee Kelvin 
Published: January 2023

Abstract
Plasma cells (PC) depend on interactions with bone marrow stroma and the resultant growth factors for their long lived survival. Very little is known about the molecular mediators of these survival signals. One such molecule that has recently come of interest is PIM2. PC malignancies such as multiple myeloma (MM) preferentially express PIM2 over its counterparts PIM1 or PIM3 downstream of the PI3K/AKT/mTOR pathway essential for differentiation and survival of PC. In this study, we explored an experimental drug JP_11646 (Jasco Pharmaceuticals LLC) that has a high potency towards PIM kinases, more specifically towards PIM2. Using MM cell lines as a model for long term PC survival, we have shown for the first time that inhibiting PIM2 deregulates survival pathways that involve IL-6, DC protection of MM and CD28 activation by deregulating key survival factors such as NFκB, decreased phosphorylation and inactivation of the PIM2 substrate and pro-apoptotic protein BAD, lower levels of the inactive phosphorylated translational repressor 4EBP1, besides affecting transcription and translation of PIM2 itself. This was recapitulated when PIM2 was silenced with siRNA. Through northerns and protein assays, we also explore the transcriptional and translational dimensions involved in regulating PIM2 in plasma cells. An understanding of the role of PIM2 in MM biology will help to understand how plasma cells survive long term and maintain humoral immunity.
Plant-derived viral-like nanoparticle immunotherapy suppresses development of metastatic lung cancer (TUM10P.1058)
Authors: Lizotte Patrick , Wen Amy , Steinmetz Nicole , Fiering Steven 
Published: January 2023

Abstract
Conventional chemo- and radiotherapy are largely ineffective for metastatic melanoma and emerging immune checkpoint inhibitors, while promising, remain ineffective in the majority of patients and carry associated autoimmune side effects. We hypothesized that treatment of lung tumor-bearing mice with a viral-like nanoparticle could modulate the lung immune environment and prevent the development of B16F10 metastatic-like lesions. We report here that inhalation of a self-assembling viral-like particle derived from the cowpea mosaic virus (CPMV) suppresses the development of tumors in the lungs of intravenous challenged mice. The disparity in tumor burden between CPMV- and PBS-treated mice was pronounced, and the effect was immune-mediated as it was not seen in Ifn-γ-/-, Il-12-/-, and NOD/scid/Il2Rγ-/- mice. CPMV nanoparticles were rapidly taken up by antigen-presenting cells that had trafficked to the lung following treatment and resulted in their activation and cytokine/chemokine production. CPMV particles are manufactured in plants and purified of nucleic acids and therefore are nonreplicative and free of endotoxin and other pattern recognition receptor agonists. CPMV nanoparticles are highly scalable, stable, nontoxic, and modifiable with drugs and antigens. These properties, combined with their inherent immunogenicity and significant efficacy against a poorly immunogenic tumor, present CPMV as an attractive novel immunotherapy against cancer metastatic to the lung.
Engineering anti-HIV-1 antibodies to enhance activity and increase half-life (VAC11P.1104)
Authors: Sievers Stuart , Patel Sonal , Klein Florian , Bennett Kathleen , Nussenzweig Michel , Bjorkman Pamela 
Published: January 2023

Abstract
HIV/AIDS remains one of the most serious threats to global public health. Although anti-HIV drugs have been effective among the wealthiest populations, new methods to prevent infections are needed to control HIV-1 infections globally. Strategies to combat HIV-1 benefit from structural knowledge of how antibodies recognize HIV envelope proteins and how the immune system eliminates viruses. Until recently, only a small number of broadly neutralizing antibodies against HIV-1 had been characterized, and the immunological basis for their breadth and potency remains poorly understood. However, it was recently demonstrated that antibodies could be engineered to greatly enhance their breadth and potency. Unfortunately, these and other engineering efforts can result in a decrease in antibody half-life in various animal models. This decrease in half-life correlates with polyreactivity, an increase in reactivity to a variety of antigens. In order to make better targets for passive delivery therapies, we are using a variety of computational and structure-based techniques. We have constructed several mutations in regions that have been predicted to have high aggregation propensities, and have shown that these novel reagents have reduced polyreactivity and longer in vivo half-lives, yet maintain potency in neutralization assays. Further characterization will help further our understanding of the relationship between antibody potency, polyreactivity, and half-life.
Characterization of activated B cells, a novel antigen-specific B cell population that emerges in blood after infection and vaccination in humans (VAC11P.1062)
Authors: Ellebedy Ali , Ahmed Rafi 
Published: January 2023

Abstract
Plasma cells (PCs) and memory B cells (MBCs) provide a remarkably stable humoral immune memory. In humans, antigen-specific antibody secreting cells (ASCs) and MBCs are detected in peripheral blood shortly after infection and vaccination. While ASCs can be distinguished by surface staining, the phenotype of recently generated MBCs is unknown. Here, we defined the phenotype of the latter cells, and termed them activated B cells (ABCs). We confirmed the specificity of ABCs after influenza vaccination and infection by ELISPOT (after in vitro differentiation) and by HA-specific staining. Similarly to ASCs, ABCs actively proliferate, up-regulate CD27 and down-regulate CD21. In contrast to ASCs, ABCs do not spontaneously secrete antibodies and up-regulate CD20 expression. ABCs represent a distinct lineage from ASCs as they maintained Pax5 expression and showed only a slight increase in IRF4 expression compared to naive B cells. Using this characterization, we were able to clearly distinguish ABCs and ASCs in peripheral blood of two Ebola virus-infected patients who were being cared for at Emory University Hospital. Defining ABCs is critical for addressing basic questions regarding the fundamental differences between the memory and plasma cell compartments in humans and because ABCs could be used for procuring therapeutic monoclonal Abs that may be different in terms of their protective potential from those derived from ASCs.
Identification and characterization of monoclonal antibodies suitable for development of influenza A vaccine seed virus (VAC11P.1101)
Authors: He Yu , Bucher Doris 
Published: January 2023

Abstract
The seed viruses for influenza A vaccine production are high-yield (hy) reassortant viruses generated in embryonated chicken eggs by reassorting wild type (wt) viruses with a hy donor virus, A/Puerto Rico/8/1934 (PR8). Currently, reassortants with wt hemagglutinin (HA) and neuraminidase (NA) are selected for growth by using polyclonal antibodies (pAbs) against PR8. The efficiency and reproducibility of reassortment will be greatly enhanced with monoclonal antibodies (mAbs) which not only provide high specificity against PR8 but could also be prepared as defined reagents with guaranteed activity in unlimited quantities. In this study, from a panel of hybridoma clones prepared against PR8 surface glycoproteins, we found four HA specific mAbs with complete neutralization of PR8 virus in an in vitro plaque inhibition assay, which are designated as mAb-1B3, mAb-1H6, mAb-2A6, and mAb-2D11. All four mAbs have been shown highly specific in both in vitro and in ovo neutralization activity to PR8. Furthermore the epitopes of all four mAbs were mapped to the area around the receptor binding site (RBS) at the membrane-distal tip of HA. Their epitopes are composed of four regions of HA residues 158-172, 183-197, 208-222, and 253-267 (H1 numbering with signal sequence). The HA residues 158-172 and 253-267 are two common regions for all four mAbs, while residues 183-197 is specific for mAb-1H6 and mAb-2A6, and residues 208-222 is specific for mAb-2D11.
Anti-CCR4 antibody enhances anti-tumor immunity by modulating tumor-infiltrating Tregs in an ovarian cancer xenograft animal model (VAC12P.1121)
Authors: Chang DeKuan , Sun Jiusong , Zhu Quan , Drapkin Ronny , Matulonis Ursula , Marasco Wayne 
Published: January 2023

Abstract
Recent experimental and clinical data demonstrate that regulatory T cells (Tregs) are recruited to the tumor site where they can suppress tumor-specific immunity. Increasing evidence indicates that Treg recruitment to the tumor is mediated by the production of chemokine CCL22, a ligand of chemokine receptor CCR4, by tumor cells and tumor resident macrophages. Therefore, blocking Treg migration and function through CCL22/CCR4 axis may have therapeutic value in cancer treatment. With a mouse model bearing CCL22-secreting ovarian xenograft and tumor-specific T cells, we assessed the therapeutic effect of human anti-CCR4 antibody mAb2-3 to block or modulate immunological axes involved in tumor immune evasion. CCR4 expression was demonstrated at a high level on functional CD4+CD25+ Tregs and T cell proliferation was restored by removal of CCR4+ Tregs in vitro. In vivo examinations showed isotyping of mAb2-3 had marked effects on its mode of action: mAb2-3 IgG1 results in Treg depletion whereas IgG4 blocks in vivo chemotactic migration to CCL22-secreting ovarian cancer (OVC) cells without Treg depletion. The mAb2-3-treated mice bearing OVC xenograft and tumor-primed T cells showed the ability to inhibit Treg recruitment and resulted in potent anti-tumor immunity. The results revealed that depletion of Tregs and blockade of Treg recruitment through mAb2-3 IgG1 and IgG4, respectively, could reverse Treg suppression and improve cellular immunity against tumors.
Adenovirus 5 vaccination elicits IL-27, which impairs CD4 and CD8 T cell functionality (VAC12P.1113)
Authors: Larocca Rafael , Provine Nicholas , Iampietro M. , Borducchi Erica , Penaloza-MacMaster Pablo , Bricault Christine , Blass Eryn , Parenteau Lily , Blackmore Stephen , Stephenson Kathryn , Barouch Dan 
Published: January 2023

Abstract
In pre-clinical studies Ad26 has shown increased protective efficacy compared to Ad5. We hypothesize this is due, in part, to differences in phenotype and function of the elicited CD4 and CD8 T cell responses. Thus, our goal is to elucidate the phenotypic differences of the CD4 and CD8 T cell repertoire following Ad5 or Ad26 vaccination and the underlying mechanism. B6 mice vaccinated with Ad5 upregulate PD1 and Tim3 (p&lt;0.01) expression on both CD4 and CD8 T cells 10 days post-immunization. On day 60, high PD1 and low CD226 expression (P&lt;0.01) was observed following only Ad5 immunization. Ad5, but not Ad26, induced a population of regulatory CD4 T cells that co-produce IFN-γ and IL-10 (p&lt;0.01). In Ad5 vaccinated non-human primates we also observed elevated expression of PD-1 and production of IL-10 (p&lt;0.01), and less IL-2 expression by CD4 T cells. Mouse DCs stimulated in vitro with Ad5 showed a four-fold increase on Il27 mRNA compared to Ad26 stimulated cells. Immunization of IL-27ra KO mice with Ad5 resulted in downregulation of IL-10 (p&lt;0.01), and up-regulation of IL-2 and CD226 (p&lt;0.01) by CD4 T cells compared to WT. CD8 T cells from KO mice exhibited increased TNF-α and IL-2 polyfunctionality (p&lt;0.01). These data demonstrate that Ad5 vaccination induces greater IL-27 production that drives inhibitory molecule expression and dysfunctional cytokine secretion by CD4 and CD8 T cells. These data suggest a mechanistic explanation for one reason why Ad5 is a suboptimal vector.
Denileukin diftitox reduces EL4 lymphoma growth by depleting regulatory T cells, which can be improved by αICOS (VAC12P.1116)
Authors: Liu Yang , Padron Alvaro , Drerup Justin , Dao Vinh , Liu Aijie , Hurez Vincent , Curiel Tyler 
Published: January 2023

Abstract
Immunotherapy shows promise in carcinoma treatments. As less is known about effects on lymphomas, we tested EL4 T cell lymphoma. We found that EL4 cells were CD25-CTLA4-B7H1loPD1hi by flow cytometry. Immune checkpoint blockade with αCTLA4, αB7H1, or αPD1 antibodies had no effect on tumor growth in EL4-challenged mice. αCD25 worked as prophylaxis (before EL4 challenge) but not therapy, despite depleting regulatory T cells (Tregs). In Foxp3DTR mice, specific Treg depletion reduced EL4 tumor growth, suggesting Treg depletion as a good treatment strategy. Denileukin diftitox (DD) is a relatively-specific Treg depletion drug with clinical benefits in mouse and human cancer. DD (5 μg/4 days starting 4 days after EL4 challenge) significantly delayed EL4 tumor growth and increased survival (P=.002) in WT mice. DD protection was lost in βδ TCR KO mice lacking all T cells, suggesting a T cell dependent treatment mechanism. In EL4-challenged WT, DD depleted Tregs &gt; αCD25 but significantly increased ICOS by 2-fold on remaining Tregs &gt; than on CD4+ or CD8+ T cells in tumor draining lymph nodes. Nearly all Tregs within tumors were ICOS+. ICOS+ Tregs were mostly CD44+ with hi Ki-67, suggesting activation that reduced DD treatment effects. In support, αICOS (100 μg/4 days starting 1 day after DD) enhanced DD-mediated EL4 tumor growth inhibition, but did not improve overall survival. DD-mediated Treg depletion plus αICOS and/or other adjuncts could lead to effective lymphoma immunotherapy.
Tumor pericyte-associated antigens DLK1 and DLK2 as targets for cancer immunotherapy (VAC13P.1131)
Authors: Fabian Kellsye , Storkus Walter 
Published: January 2023

Abstract
The vasculature of solid tumors is essential for their progressive growth and is abnormal structurally and functionally. Notably, pericytes and vascular endothelial cells (VEC) in tumors exhibit altered epigenetic programming and express antigens that allow for their differential recognition (vs. vascular cells in normal tissues) by therapeutic T cells. Therefore, targeting immune reactivity against these antigens via specific vaccination may be a viable therapeutic approach against solid tumors. We show that pericytes isolated from human and murine renal cell carcinoma (RCC) and melanoma overexpress the antigens Delta-like homologue 1 (DLK1) and its homologue DLK2. Using recombinant lentiviruses and adenoviruses encoding full-length murine DLK1 and DLK2 proteins, we show that coordinate genetic vaccination against these two antigens leads to superior therapeutic inhibition of RENCA and B16 tumor growth in vivo when compared to tumor-bearing mice vaccinated against either DLK1 or DLK2 alone. The coordinate vaccination protocol also resulted in the activation of DLK1- and DLK2-specific CD8+ T cells, recruitment of T cells into the tumor microenvironment, loss of DLK1 and DLK2 expressing pericytes and structural normalization of tumor-associated blood vessels. We conclude that specific vaccination against (oncofetal) DLK1 and/or DLK2 may represent an effective strategy for the treatment of vascularized, solid forms of cancer (including RCC and melanoma, among others).
Interferon epsilon protects primary human macrophages against HIV-1 infection by blocking early stages of the viral life cycle (VIR9P.1152)
Authors: Tasker Carley , Chang Theresa 
Published: January 2023

Abstract
Interferon epsilon (IFNε), a type-I IFN, is hormonally regulated and plays a protective role against several viral and bacterial pathogens. In this study, we examined the effect of IFNε on HIV infection and its underlying mechanism. IFNε at 10ng/mL inhibited HIV infection of human monocyte derived macrophages (MDMs) but not activated CD4+ T cells. Pretreatment of MDMs with IFNε protected MDMs against infection by replication competent X4, R5, and X4R5 dual-tropic viruses and HIV transmitted/founder viruses. We further delineated the underlying mechanism of the anti-HIV activity of IFNε and found IFNε down-regulated cell surface expression of the co-receptor CCR5 but not CD4 or the co-receptor CXCR4. Although IFNε treatment affected HIV entry, it also blocked infection by HIV reporter virus pseudotyped with VSV envelope, which enters cells independently of CD4 and HIV co-receptors, indicating that IFNε treatment inhibited HIV infection after viral entry. Quantitative PCR analysis of HIV reverse transcribed (RT) DNA products revealed IFNε blocked the step of early RT. IFNε induced expression of the HIV host restriction factor APOBEC3A in MDMs, however siRNA knockdown of A3A determined it may not play a significant role in IFNε mediated HIV inhibition. Taken together, IFNε protects MDMs against HIV infection through multiple mechanisms by down-regulation of CCR5 expression and by inhibiting the synthesis of HIV reverse transcribed products.
Phosphorylation of STAT1 and NF-κB by human plasmacytoid dendritic cells during HIV-infection (VIR9P.1154)
Authors: Serei Virian , Dai Jihong , Fitzgerald-Bocarsly Patricia 
Published: January 2023

Abstract
Plasmacytoid dendritic cells (pDC) are critical for anti-viral immunity. TLR7 and TLR9 allow pDC to recognize viruses and initiate signals leading to IRF7 phosphorylation, which is responsible for IFN-α production, as well as NF-κB phosphorylation, which is responsible for TNF-α and IL-6 induction. During HIV-infection, lower pDC numbers are found, along with impaired IFN-α production. Chronic immune activation is also found, with patients paradoxically displaying an IFN-signature, indicating the presence of IFN-α, and higher serum TNF-α and IL-6. To see if pDC are affected in vivo by IFN-α or TNF-α, we compared baseline p-STAT1 and p-NF-κB in pDC in HIV-patients vs healthy controls. At baseline, HIV-patient vs. healthy pDC showed a trend towards elevated p-STAT1, while p-NF-κB levels were similar. HIV-patient pDC phosphorylated STAT1 and NF-κB less than healthy controls in response to IFN-α and TNF-α, respectively. In response to viruses, HIV-patient pDC phosphorylated STAT1 more than healthy controls. Despite normal production of TNF-α and IL-6, HIV-patient pDC were unable to phosphorylate NF-κB in response to viruses, suggesting that other mechanisms exist for TNF-α and IL-6 induction. In conclusion, impaired NF-κB phosphorylation by HIV-patient pDC suggest that they are immunologically exhausted and this can lead to a number of downstream effects on protein expression. In contrast, enhanced p-STAT1 in response to viruses can drive the IFN-signature seen in HIV-patients.
Regulatory CD4 T cells differentially modulate HIV-1 infection of polarized M1 and M2 macrophages (VIR9P.1156)
Authors: Robinson Tanya , Zhang Mingce , Lowe Robert , Cron Randy 
Published: January 2023

Abstract
Macrophages are long-lived, widely distributed and relatively resistant to HIV-1 cytotoxicity. Effector macrophages are functionally polarized into M1 (pro-inflammatory) and M2 (anti-inflammatory) phenotypes. M1 macrophages suppress CCR5 (R5) HIV-1 replication, while M2 macrophages promote it. Recently, regulatory CD4 T cells (Tregs) were shown to inhibit HIV-1 infection of co-cultured CD4 T cells, but their effect on macrophage infection is unknown. Using an in vitro model of polarization, we generated M1 (GM-CSF+IFN-γ+LPS) and M2 (M-CSF+IL-4) macrophages with predicted phenotypes and infected them with R5 HIV-1 reporter viruses. We consistently found higher levels of HIV-1 (GFP and luciferase reporter viruses) infection of the M2 cells. Next, we co-cultured Tregs with HIV-1 infected polarized M1 and M2 MDM at a 1:1 ratio. Treg co-cultures yielded decreased HIV-1 infection of M1 but increased infection of M2 macrophages. Surprisingly, our results showed that Tregs mediate divergent effects on HIV-1 infection of M1 and M2 MDM depending on their polarization into a M1 or M2 phenotype. We are currently exploring whether Treg-mediated effects on HIV-1 infection of MDM are cytokine dependent and/or cell contact dependent using a transwell system and inhibitory cytokine antibodies. The research will provide increased knowledge of the role Tregs play in HIV-1, as well as a new understanding of how the M1 to M2 macrophage switch contributes to HIV-1/AIDS pathogenesis.
PSGL-1, an immune checkpoint regulator that promotes T cell exhaustion in chronic viral infection and cancer (VIR10P.1166)
Authors: Tinoco Roberto , Carrette Florent , Barraza Monique , Magana Jonathan , Swain Susan , Bradley Linda 
Published: January 2023

Abstract
Chronic viruses, including HIV and hepatitis B and C, can survive in humans by inducing T cell dysfunction. Using a murine chronic virus that models human infections, we investigated the function of the adhesion molecule, P-selectin glycoprotein ligand-1 (PSGL-1) that is upregulated on responding T cells. PSGL-1-deficient mice unexpectedly cleared the virus due to dramatic increases in the intrinsic survival of multifunctional effector T cells that had downregulated PD-1 and other inhibitory receptors. Notably, this response resulted in immunopathology requiring CD4+ T cells. Mechanistically, PSGL-1 ligation on exhausted CD8+ T cells sustained PD-1 expression and diminished their survival during TCR stimulation. In a model of malignant melanoma where T cell dysfunction also occurs, PSGL-1 deficiency led to PD-1 downregulation, improved T cell responses and tumor control. Thus, PSGL-1 not only plays a fundamental role in balancing viral control and immunopathology, but also functions as a checkpoint that regulates T cell function in the tumor microenvironment.