bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of Antigen Processing Molecules in Adenovirally Engineered Human Dendritic Cells (48.10)
Authors: Vujanovic Lazar , Whiteside Theresa L. , Ferrone Soldano , Butterfield Lisa H. 
Published: January 2023

Abstract
Multiple strategies utilizing the inherent immunostimulatory ability of dendritic cells (DC) are being tested as cancer vaccines. Our group has focused on recombinant adenoviral vectors (AdV) as vehicles for antigen engineering of DC in order to harness their immunostimulatory ability and activate multiple tumor antigen-specific T cell specificities. Previously we have found that AdV transduction can skew DC towards mature phenotype, and that cytokine-induced maturation of DC can upregulate the level of key components of antigen processing machinery (APM). In this study we have investigated the effects of AdV transduction on APM component expression levels in human DC and have compared these values to the level of APM components in immature (iDC) and in IFN-γ/LPS-matured (mDC) DC. The level of surface markers and of APM components in DC transduced with AdV was intermediate between that in iDC and in mDC, suggesting that AdV induces an intermediary level of DC maturation. Immunoproteasome subunits LMP2 and LMP7, peptide transporter TAP2 and chaperone tapasin are upregulated after AdV transduction. Interestingly, peptide transporter TAP1, which is upregulated in mDC, shows little change in AdV-infected DC when compared to iDC. Together, this data elucidates vital molecular changes in AdV-transduced DC that could influence T cell priming and that should be considered when designing effective cancer vaccines.
This work was supported by a Scientist Development Grant from the American Heart Association (#0330102N), the University of Pittsburgh Cancer Institute and the Henry L. Hillman Foundation (to L.H.B.)
Xenogeneic tyrosine hydroxylase DNA vaccination is effective against neuroblastoma (48.14)
Authors: Lode Holger N , Huebener Nicole 
Published: January 2023

Abstract
Neuroblastoma cells are derived from sympathetic neuroblasts and express high amounts of tyrosine hydroxylase (TH), the first step enzyme in catecholamine biosynthesis. We demonstrated that expression profiles of 68 neuroblastoma revealed stable TH gene expression independent of stage and MYCN amplification. Here, we report that a xenogeneic immunization with TH DNA vaccines induces an anti-neuroblastoma immune response in vivo.
For this purpose, three DNA vaccines were designed: one encoding for the whole coding sequence of the human TH gene (hTH) (cDNA). The second vaccine was constructed using the epitope prediction program syfpeithi: it comprises of three hTH derived epitopes with high predicted binding affinity to MHC class I with the epitopes separated by an AAY-spacer peptide. In order to amplify the immune response we designed a third DNA vaccine encoding for the hTH gene and single chain (sc)IL-12. The bifunctional characteristics of this construct, antigen expression and IL-12 bioactivity, were demonstrated in vitro.
The induction of protective immunity against neuroblastoma was determined in vivo using strain SL7207 of Salmonella typhimurium as an oral vehicle for the DNA vaccines. Interestingly, the hTH cDNA vaccine and the hTH minigene vaccine were equally efficient in inducing T-cell mediated suppression of subcutanous tumor growth and could effectively protect mice from spontaneous liver metastasis. Furthermore, the introduction of scIL-12 did not further amplify the anti-tumor immune response indicating the efficiency of the “danger signal” provided by the bacterial vaccine vehicle.
The results indicate that xenogeneic immunization is a promising concept for active immunotherapy in neuroblastoma patients.
Supported by DFG (Lo635/2).
Modulation of adenoviral vector immune responses through the over-expression of immune adaptor and viral immuno-modulatory genes (48.17)
Authors: Hartman Zachary , Yang Xiao Yi , Lei Gangjun , Amalfitano Andrea , Morse Michael , Lyerly Herbert Kim , Clay Tim 
Published: January 2023

Abstract
For the past two decades, adenoviral vector platforms have been used as both gene therapy vehicles and vaccine platforms in various human clinical trials. However, the use of these, as well as other viral vector platforms, has been tempered by the innate immune and adaptive immune responses elicited. Despite the development of advanced generation adenoviral vectors, the innate responses precipitated by these vectors have remained largely unchanged due to the particular nature of the viral capsid and infectious process. To more effectively use these vectors for different purposes, we constructed adenoviral vectors encoding overexpression cassettes for various TLR adaptors (MyD88 and TRIF), RIG-I pathway adaptor (MAVS), as well as immuno-modulatory viral genes (pp65) whose expression might accentuate or inhibit the innate immune response enabled by adenoviral infection. Our studies show that while all of these immuno-modulatory vectors were able to effectively enhance (TLR and MAVS vectors) or inhibit (pp65 vectors) the NF-kB and IFN-beta responses in vitro, only certain vectors were able to affect the adaptive responses elicited in vivo. While our findings show that vector manipulation can influence vector-specific innate and adaptive immune responses, they also offer evidence for the highly regulatory nature of the innate response, as evidenced by the limited impact of certain adaptor overexpression.
Immunization with PSA/anti-PSA complexes induces T and B cell responses to PSA in PSA-transgenic mice (48.19)
Authors: Schultes Birgit Corinna , Hou Fuxiang , Smith L. Mary , Nicodemus Christopher F. , Frelinger John F. 
Published: January 2023

Abstract
The murine MAb-AR47.47 (IgG1κ) recognizes all circulating forms of PSA and targets the epitope EPEEFLT. In vitro studies showed that human and murine dendritic cells process PSA more efficiently in immune complexes (IC) with MAb-AR47.47. IC induced CD4+ and CD8+ IFN-γ producing T cells, whereas PSA alone or PSA combined with a non-specific antibody mainly stimulated CD4+ T cells. We have further investigated the activation of PSA-specific immune responses with IC in male PSA-transgenic mice, which express human PSA in the prostate. Mice were immunized with PSA and MAb-AR47.47 alone or IC consisting of MAb-AR47.47 and PSA at various concentrations. To investigate the need for foreign antibody in inducing immune responses, rabbit and goat polyclonal anti-PSA antibodies or MAb-AR47.47-ovalbumin were tested in parallel. The mice only generated a weak T helper 2 response to immunization with PSA alone. Robust T helper 1 and 2, CTL and antibody responses were induced in mice immunized with AR47.47-PSA IC. Interestingly, IC with PSA and the polyclonal goat or rabbit antibodies or MAb-AR47.47-ovalbumin induced stronger T helper cell responses to PSA, but resulted in weaker CTL induction relative to IC with MAb-AR47.47. This data indicates that AR47.47-PSA IC can prime B cells, T helper cells and CTL against the tumor antigen PSA in vivo in a setting where PSA is a self antigen.
Sensitization of murine B16 melanoma cells with the HDAC inhibitor depsipeptide promotes immune cell-mediated tumor destruction (48.24)
Authors: Murakami Takashi , Sato Atsuko , Furukawa Yusuke , Kobayashi Eiji 
Published: January 2023

Abstract
Histone deacetylase inhibitor (HDACi) can restore gene expression that is aberrantly repressed in refractory cancer. Our recent DNA microarray analysis demonstrated that HDACi depsipeptide markedly augments expression of gp100/pmel17 melanoma antigen (15 fold), which is repressed in human melanoma cell lines. Herein, we set out to determine whether depsipeptide enhances tumor-specific T-cell-mediated killing of B16 murine melanoma cells. Firstly, by a quantitative assay of caspase-3/7 activity, we determined a sublethal dose of depsipeptide in vitro (ED50: ~5nM, after 24 hr), in which p21Waf1/Cip1, MHC class I and Fas were induced concomitantly with an increased level of histone H3 acetylation (~3 fold). Secondly, depsipeptide (5 nM) with Fas engagement synergistically promoted apoptosis in B16 cells (p&lt;0.05, vs. depsipeptide; p&lt;0.001, vs. FasL). Gp100-specific cytotoxic T cells also killed depsipeptide-treated B16 cells more efficiently than untreated B16 cells in vitro (p&lt;0.01). Furthermore, in vivo metastatic growth of B16/F10 to the lung of C57BL/6 mice was synergistically suppressed by a combination of depsipeptide (2 mg/kg, i.p. only at day 1 following tumor implantation) with immune cell adoptive transfer (p=0.015, vs. PBS treatment, at day 20). Consequently, a transcriptional modulation strategy using HDACi might prove to be a useful adjunct in cancer immunotherapy.
Importance of Decay Accelerating Factor(CD55) in Tumor Avoidance of Immune Destruction (48.27)
Authors: Li Bing , Allendorf Daniel , Hansen Richard , Marroquin Jose , Cramer Daniel , Harris Claire , Yan Jun 
Published: January 2023

Abstract
Combined yeast derived β-glucan in conjunction with anti-tumor mAb therapy have demonstrated significant therapeutic efficacy. Therefore, we tested this strategy using human carcinomas implanted in immunocompromised SCID mice. Surprisingly, combined therapy achieved significant therapeutic efficacy in NCI-H23 human non-small cell lung carcinoma but failed in SKOV-3 human ovarian carcinoma. Immunohistochemistry analysis demonstrated markedly decreased levels of neutrophil infiltration and C5a deposition in SKOV-3 tumors compared to that in NCI-H23 tumors. Membrane complement regulatory proteins such as CD46 and CD55 were up-regulated in SKOV-3 cells. Blockade of CD46 and CD55 in vitro led to enhanced deposition of complement C3 activation product C3b on SKOV-3 cells. However, β-glucan-elicited in vitro CR3-dependent cellular cytotoxicity was only augmented in the presence of anti-CD55 mAb. To investigate the role of CD55 in the regulation of β-glucan mediated immunotherapy in vivo, anti-CD55 mAb was co-administered with yeast β-glucan and anti-Her-2/neu mAb to treat previously failed SKOV-3 tumors. Strikingly, significant tumor regression and long term survival were achieved in this model. Blockade of CD55 in vivo also restored neutrophil influx into tumor and C5a deposition. Thus, these studies identify a critical role for CD55 to regulate iC3b and C5a release and in turn to influence the recruitment of β-glucan primed neutrophils eliciting killing activity.
Two Chemotactic, Melanoma-Associated Proteins Stimulate Dendritic Cells (48.3)
Authors: Buzas Krisztina , Oppenheim Joost J , Howard OM Zack 
Published: January 2023

Abstract
IL-24 (melanoma differentiation associated gene 7 product) was initially identified as a melanoma associated antigen. IL-24 is actually a rapidly acting Th1 cytokine, IL-10 family member, induces selective apoptosis of tumor cells in vitro, and its expression correlates with melanoma tumor progression. The melanoma-associated antigen, gp100, mediates intracellular trafficking steps that regulate melanosome biogenesis. We have previously observed that self-antigens; including autoimmune and tumor antigens, induce cell migration by interacting with chemokine receptors. Further, we have reported that recombinant gp100 induces cell migration by interacting with CCR2. To further identify domains likely to be responsible for gp100 induced migration, 20 amino acid peptides spanning the first 140 amino acids of the mature human gp100 were synthetized and tested. One of the peptides, P3859, induces cell migration. We tested the chemotactic activity of rmuIL-24 for CCR2 positive monocytes. We found that rmuIL-24 induced human monocyte migration at 0.125–0.0125 ng/ml. Pertussis toxin, a Gi coupled protein receptor inhibitor, can reduce this effect, while a JAK inhibitor blocks the cell migration toward IL-24, suggesting a role for IL20R2 in the chemotactic signal transmitted by rmIL24. We tested the effect of the gp 100 melanoma antigen on IL-24 production by bone marrow derived dendritic cells. Data showed that gp100, P3859, and supernatant from B16 cells induced IL-24 transcription and expression by DC. These studies indicate that gp100 and rmuIL24 share a chemotactic activity and suggest that a crosstalk between CCR2 and IL20R2.
CD8 T cells with high avidity TCR-ab specific for serine protease self-determinants for use in adoptive immunotherapy of human leukemia (48.35)
Authors: Rusakiewicz Sylvie , Kant Shreya , Lizee Gregory , Rabinovich Brian , Wieder Eric , Lu Sijie , Hwu Patrick , Molldrem Jeffrey J. 
Published: January 2023

Abstract
Specific cytotoxic T-lymphocyte (CTL) immunity against the serine protease-derived PR1 peptide has been correlated with clinical response (CR) to interferon-α, allogeneic bone marrow transplantation or PR1-peptide vaccination in leukemia patients. However, some patients failed to demonstrate a CR, despite an immunological response. Patients with CR have functional PR1-CTL with a preferentially higher avidity T cell receptor (HTCR). These HTCR PR1-CTL were more susceptible to apoptosis by high PR1 peptide expression on leukemia cells compared to low avidity (LTCR) PR1-CTL, suggesting deletional tolerance mediated by the leukemia cells. We hypothesized that the adoptive transfer of HTCR PR1-CTL could induce remission in leukemia patients. Clonal, HTCR and LTCR PR1-CTL were elicited from an HLA-A2 healthy donor using low (2 μM) or high (200 μM) concentration of PR1 peptide, respectively. TCR affinity of these clones correlated with tetramer fluorescence intensity and importantly, effector function. Jurkat and primary T cells transduced with HTCR or LTCR by lentivirus vectors expressed cell surface PR1-specific TCR complex and specifically recognized the HLA-A2/PR1 tetramers. HTCR-αβ genes transduction represents a powerful strategy for adoptive immunotherapy in leukemia patients.
Alpha-enolase elicits specific pancreatic adenocarcinoma specific-T cell responses in healthy donors and in tumor patients (48.4)
Authors: Novelli Francesco , Tomaino Barbara , Ciccarelli Marianna , Capello Michela , Giovarelli Mirella , Novarino Anna , Cappello Paola 
Published: January 2023

Abstract
We have demonstrated that sera from pancreatic ductal adenocarcinoma (PDAC) patients contain IgG autoantibodies to α-enolase, a glycolytic enzyme that also works as surface plasminogen receptor. As this implies that α-enolase elicits a B-cell dependent humoral response in vivo in PDAC patients, its ability to induce a T cell mediated response to PDAC was investigated. Here we show that α-enolase-pulsed dendritic cells were capable to specifically stimulate healthy autologous T cells to proliferate, secrete IFN-γ and lyse PDAC cells. In vivo, α-enolase-specific T cells completely inhibited the growth of PDAC cells in immunodeficient mice. In PDAC patients, and in particular in those with circulating IgG autoantibodies to α-enolase, the existence of memory T cells to α-enolase was also demonstrated. As a whole, these results indicate that α-enolase elicits a PDAC-specific humoral and cellular responses. The sum of its features makes α-enolase a promising candidate for new immunotherapeutic strategies in the cure of PDAC that lacks until now of efficacious therapies to associate the conventional ones.
A novel role of myeloid related protein in dendritic cell differentiation (49.11)
Authors: Cheng Pingyan , Yu Bin , Nadaf Sorena , Carbone David P. , Nacken Wolfgang , Sorg Clemens , Gabrilovich Dmitry I. 
Published: January 2023

Abstract
Abnormal differentiation of dendritic cell (DC) is a critical factor contributing into ineffective immune response in cancer. We have searched for the genes that could be involved into tumor-induced defects in DC differentiation and found that tumor-derived factors consistently up-regulated expression of myeloid related protein 14 (MRP14) and its partner MRP8 in hematopoietic progenitor and myeloid cells during DC differentiation. Normal DC differentiation was associated with dramatic down-regulation of MRP14/8, whereas accumulation of immature myeloid cells was associated with persistently high levels of these proteins. Overexpression of these proteins in embryonic stem cells resulted in inhibition of DC differentiation and accumulation of immature myeloid cells able to form myeloid colonies. It is known that Gr-1+ myeloid-derived suppressor cells (MDSC) frequently accumulate in tumor-bearing mice and during in vitro DC differentiation in the presence of tumor-derived factors. We have found that in tumor-bearing mice MRP14/8 were exclusively accumulated in MDSC. Accumulation of these proteins was controlled by up-regulation of STAT3. MRP14/8 knockout mice had normal level of DCs or MDSC suggesting that MRP proteins were not required for accumulation of MDSC in cancer. Thus, this study demonstrates that tumor-induced up-regulation of MRPs inhibits DC differentiation, which may suggest a novel molecular mechanism of tumor-induced abnormalities in myeloid cells in cancer.
Understanding the Interplay of the Human Immune System with Cancer in Humanized Mice (49.17)
Authors: Pedroza-Gonzalez Alexander , Aspord Caroline , Gallegos Michael , Tindle Sasha , Burton Elizabeth , Marches Florentina , Banchereau Jacques , Palucka Anna K. 
Published: January 2023

Abstract
The paucity of in vivo models of human disease represents a major drawback in translational research. Indeed, the results obtained in mice cannot always be directly extrapolated to humans because of differences between the species. We have used humanized mice to study the human immune system, particularly DCs in vivo in human cancer. There, nonobese diabetic/LtSz-scid/scid β2m−/− mice engrafted with human CD34+ hematopoietic progenitors develop all subset of human DCs. They also develop B cells but T cells need to be adoptively transferred. In this model, we implanted human tumor cell lines derived from melanoma and breast cancer. Breast cancer attracts human dendritic cells and polarizes them to prime naïve CD4+T cells to secrete IL-13. CD4+T cells accelerate tumor development, which can be inhibited with IL-13 antagonists. CD4+T cells secreting IL-13 can be identified in tumor samples from breast cancer patients. Frozen tissue sections reveal IL-13 staining on breast cancer cells. The expression of phosphorylated STAT6 suggests that actually IL-13 delivers signals to breast cancer cells. Thus, breast cancer promotes skewed DC maturation leading to polarized adaptive immune response that facilitates tumor development. This model can thus be used to decipher pro-cancer mechanisms thereby guiding us in the development of novel anti-cancer therapies.
Supported by U19 AIO57234, RO-1 CA89440, CA78846 and CA85540
Increased Levels of Circulating CD4+CD25+ T cells (T-regs) Correlate with Clinical Cancer Stage And Inversely Correlate with CD8+ T cell Frequency (49.18)
Authors: Al-Khami Amir , Montero Alberto J. , Salem Mohamed L. , Vissage Kristi , Cole David J. , Diaz-Montero C. Marcela 
Published: January 2023

Abstract
Regulatory T cells inhibit immune responses mediated by T cells. Increased circulating levels of T-regs in patients (pts) have been reported in some solid tumors. Moreover, increased apoptosis among circulating CD8+ T cells has been reported in cancer pts. The goal of our study was therefore to determine how levels of circulating T-regs and CD8+T cells correlate with clinical cancer stage in a diverse cohort of pts. Flow cytometry analyses were performed on whole blood from 14 normal healthy controls and 35 cancer pts with newly diagnosed tumors prior to any therapy (stages: I/II, n=12; III/IV n=23). Although no significant difference was observed in T-regs between normal and stage I/II cancer pts (4.36% vs. 4.92%), levels were significantly increased in stage III/IV pts (7.26%; p=0.039). Moreover, there was an inverse correlation between CD8+T cell frequencies and clinical cancer stage, with stage III/IV pts having the lowest levels relative to normal (3.97% vs. 7.01%; p=0.036). In conclusion, T-regs were increased only in pts with advanced stage III/IV cancer and percentage of total CD8+T cells inversely correlated with clinical tumor stage. Thus, increased levels of T-regs and decreased levels of CD8+ T cells might contribute to cancer-mediated immunosupression.
Osteopontin induced STAT1 ubiquitination and degradation enhances cell proliferation (49.2)
Authors: Gao Chengjiang , Guo Hongtao , Kuo Paul C. 
Published: January 2023

Abstract
Signal transducer and activator of transcription 1 (STAT1) is a very important downstream component in interferon signaling required for the maximum induction of IFN responsive genes. IFN/STAT1 signaling composes a very important tumor-suppressor system to protect hosts against tumor development. At the same time, tumors can become insensitive to IFN/STAT1 signaling and thereby escape immune detection and elimination. But, the genetic mechanisms employed by tumors to become IFN/STAT1 insensitive was poorly defined. Osteopontin (OPN) is a pleiotropic cytokine that participates in a wide range of biological processes, including bone remodeling, inflammation and cancer metastasis. We found OPN can induce STAT1 ubiquitination and degradation in breast cancer cells. In addition, we identify STAT- interacting LIM (SLIM) protein as the STAT ubiquitin E3 ligase critical for STAT1 degradation in this setting. Consequently, p21WAF1/CIP1 expression was down-regulated. Therefore, cancer cells showed very strong proliferation ability upon IFN-gamma stimulation. Given that STAT1 is a tumor suppressor and OPN is highly expressed in metastatic cancers, these findings maybe can shed light about how invasive cancers can escape from tumor surveillance.
This work was supported by National Institutes of Health Grants AI44629, GM65113, and GM069331.
Recognition and cleavage of cryptic recombination signal sequences identified from lymphoid malignancies (49.20)
Authors: Zhang Ming , Swanson Patrick C. 
Published: January 2023

Abstract
Immune repertoire diversity is largely achieved by V (D) J recombination, during which antigen receptor genes are assembled from arrays of component gene segments by site-specific DNA rearrangement. This process is initiated when the RAG proteins introduce DNA double-strand breaks (DSBs) at recombination signal sequences (RSSs) abutting antigen receptor coding segments. However, the RAG proteins occasionally mistarget DNA sequences outside of antigen receptor loci and promote chromosomal translocations and deletions, which are among the major events that initiate neoplasia in lymphoid organs. Previous studies have identified various RSS-like sequences involved in chromosomal translocations, including LMO2, TAL1, Ttg-1, and Hox11, and the interstitial deletion at 1p32 involving SIL/SCL. Here we have used electrophoretic mobility shift assays and in vitro cleavage assays to study RAG-mediated binding and cleavage to the oligonucleotide substrates containing these cryptic RSSs. We find that RAG proteins can cleave LMO2, TAL1, Ttg-1, and SIL in vitro, and introduce DSBs at these sites which can be detected by ligation-mediated PCR in cell culture. In contrast, Hox11 and SCL are nicked but fail to support DSB formation both in vitro and in cell culture. These data raise the possibility that Hox11 and SCL may be cleaved by an as-yet unidentified mechanism.
This research is supported by American Cancer Society grant RSG-01-020-05-LIB to P.C.S.