In pancreatic cancer patients, chemotherapy reshapes the gene expression profile and antigen receptor repertoire of T lymphocytes and enhances their effector response to tumor-associated antigens.

Introduction: Pancreatic Ductal Adenocarcinoma (PDA) is one of the most aggressive malignancies with a 5-year survival rate of 13%. Less than 20% of patients have a resectable tumor at diagnosis due to the lack of distinctive symptoms and reliable biomarkers. PDA is resistant to chemotherapy (CT) and understanding how to gain an anti-tumor effector response following stimulation is, therefore, critical for setting up an effective immunotherapy. Methods: Proliferation, and cytokine release and TCRB repertoire of from PDA patient peripheral T lymphocytes, before and after CT, were analyzed in vitro in response to four tumor-associated antigens (TAA), namely ENO1, FUBP1, GAPDH and K2C8. Transcriptional state of PDA patient PBMC was investigated using RNA-Seq before and after CT. Results: CT increased the number of TAA recognized by T lymphocytes, which positively correlated with patient survival, and high IFN-γ production TAA-induced responses were significantly increased after CT. We found that some ENO1-stimulated T cell clonotypes from CT-treated patients were expanded or de-novo induced, and that some clonotypes were reduced or even disappeared after CT. Patients that showed a higher number of effector responses to TAA (high IFN-γ/IL-10 ratio) after CT expressed increased fatty acid-related transcriptional signature. Conversely, patients that showed a higher number of regulatory responses to TAA (low IFN-γ/IL-10 ratio) after CT significantly expressed an increased IRAK1/IL1R axis-related transcriptional signature. Conclusion: These data suggest that the expression of fatty acid or IRAK1/IL1Rrelated genes predicts T lymphocyte effector or regulatory responses to TAA in patients that undergo CT. These findings are a springboard to set up precision immunotherapies in PDA based on the TAA vaccination in combination with CT.

Predicting Antigen-Specificities of Orphan T Cell Receptors from Cancer Patients with TCRpcDist.

Approaches to analyze and cluster T-cell receptor (TCR) repertoires to reflect antigen specificity are critical for the diagnosis and prognosis of immune-related diseases and the development of personalized therapies. Sequence-based approaches showed success but remain restrictive, especially when the amount of experimental data used for the training is scarce. Structure-based approaches which represent powerful alternatives, notably to optimize TCRs affinity toward specific epitopes, show limitations for large-scale predictions. To handle these challenges, TCRpcDist is presented, a 3D-based approach that calculates similarities between TCRs using a metric related to the physico-chemical properties of the loop residues predicted to interact with the epitope. By exploiting private and public datasets and comparing TCRpcDist with competing approaches, it is demonstrated that TCRpcDist can accurately identify groups of TCRs that are likely to bind the same epitopes. Importantly, the ability of TCRpcDist is experimentally validated to determine antigen specificities (neoantigens and tumor-associated antigens) of orphan tumor-infiltrating lymphocytes (TILs) in cancer patients. TCRpcDist is thus a promising approach to support TCR repertoire analysis and TCR deorphanization for individualized treatments including cancer immunotherapies.

Tumor antigen presentation and the associated signal transduction during carcinogenesis.

Numerous developments have been achieved in the study and treatment of cancer throughout the decades that it has been common. After decades of research, about 100 different kinds of cancer have been found, each with unique subgroups within certain organs. This has significantly expanded our understanding of the illness. A mix of genetic, environmental, and behavioral variables contribute to the complicated and diverse process of cancer formation. Mutations, or changes in the DNA sequence, are crucial to the development of cancer. These mutations have the ability to downregulate the expression and function of Major Histocompatibility Complex class I (MHC I) and MHCII receptors, as well as activate oncogenes and inactivate tumor suppressor genes. Cancer cells use this tactic to avoid being recognized by cytotoxic CD8+T lymphocytes, which causes issues with antigen presentation and processing. This review goes into great length into the PI3K pathway, changes to MHC I, and positive impacts of tsMHC-II on disease-free survival and overall survival and the involvement of dendritic cells (DCs) in different tumor microenvironments. The vital functions that the PI3K pathway and its link to the mTOR pathway are highlighted and difficulties in developing effective cancer targeted therapies and feedback systems has also been mentioned, where resistance mechanisms include RAS-mediated oncogenic changes and active PI3K signalling.

Identification of tumor rejection antigens and the immunologic landscape of medulloblastoma.

BACKGROUND: The current standard of care treatments for medulloblastoma are insufficient as these do not take tumor heterogeneity into account. Newer, safer, patient-specific treatment approaches are required to treat high-risk medulloblastoma patients who are not cured by the standard therapies. Immunotherapy is a promising treatment modality that could be key to improving survival and avoiding morbidity. For an effective immune response, appropriate tumor antigens must be targeted. While medulloblastoma patients with subgroup-specific genetic substitutions have been previously reported, the immunogenicity of these genetic alterations remains unknown. The aim of this study is to identify potential tumor rejection antigens for the development of antigen-directed cellular therapies for medulloblastoma. METHODS: We developed a cancer immunogenomics pipeline and performed a comprehensive analysis of medulloblastoma subgroup-specific transcription profiles (n = 170, 18 WNT, 46 SHH, 41 Group 3, and 65 Group 4 patient tumors) available through International Cancer Genome Consortium (ICGC) and European Genome-Phenome Archive (EGA). We performed in silico antigen prediction across a broad array of antigen classes including neoantigens, tumor-associated antigens (TAAs), and fusion proteins. Furthermore, we evaluated the antigen processing and presentation pathway in tumor cells and the immune infiltrating cell landscape using the latest computational deconvolution methods. RESULTS: Medulloblastoma patients were found to express multiple private and shared immunogenic antigens. The proportion of predicted TAAs was higher than neoantigens and gene fusions for all molecular subgroups, except for sonic hedgehog (SHH), which had a higher neoantigen burden. Importantly, cancer-testis antigens, as well as previously unappreciated neurodevelopmental antigens, were found to be expressed by most patients across all medulloblastoma subgroups. Despite being immunologically cold, medulloblastoma subgroups were found to have distinct immune cell gene signatures. CONCLUSIONS: Using a custom antigen prediction pipeline, we identified potential tumor rejection antigens with important implications for the development of immunotherapy for medulloblastoma.

Harnessing the potential of blood donors negative for high prevalence Rh antigens: A Database Initiative for Thalassaemia Care.

BACKGROUND AND OBJECTIVES: With increasing life expectancy and prevalence of thalassaemia, it has led to a greater need for safe blood, yet the current supply from voluntary donors is insufficient to meet this demand. Thalassaemia recipients face a significant risk of alloimmunization because of repeated exposure to foreign red cell antigens. Study aims to determine high prevalent Rh antigen negative donors in western India donor population along with what percentage of these donors are willing to become dedicated voluntary donors for thalassaemia patients. Study also aims to examine factors influencing their willingness and challenges faced in mobilizing dedicated donors. METHOD: 700 whole blood donors from western India, following screening for inclusion & exclusion criteria as per Drugs and Cosmetic Act (DCA) 2020 amendment guidelines & were sero-negative for transfusion transmitted infections were enrolled for the study. Red cell phenotyping was performed using Conventional Tube Technique (CTT) for "D", "C", "E", "c", "e" and "K" antigen using known antisera. Donors that were "C" AND/OR "e" antigen negative were contacted telephonically and were counseled and motivated for becoming voluntary blood donors. Statistical analysis assessed correlation between donation frequency, donor's occupation and education. RESULT: Among 700 donors, 96.6% (n=676) were males and 3.4% (n=24) were females. The most predominant blood group was B > O > A > AB. Rh(D) antigen was present in 91.44% (n = 640) and absent in 8.6% (n=60). Prevalence of other Rh antigens is as follows: "e" (99%) > "C" (85.4%) > "c" (59.1%) > "E" (18.0%). Only 1.15% had "K" antigen positive. The commonest Rh phenotype R1R1 (DCe/DCe) was expressed by 40.57% (n=283), and the least common r"r (cE/ce), r''r''(cE/cE) and r'r' (Ce/Ce) was found in 0.14% (n=1), respectively. 'C' negative, 'e' negative, 'C' and 'e' antigen negative donors constituted 14.8% (n = 104) with 93.2% (n=97) C-antigen negative, 1.92% (n=2) e-antigen negative and 4.8% (n=5) both "C" and "e" antigen negative donors. The commonest phenotypes among C-antigen and e-antigen negative donors were rr (50%) and RzR2 (1.94%) respectively. Likewise, the most common phenotype amongst both C- and e-antigens negative donors was R2R2 (3.84%). 61.5% of the donors agreed to enroll for voluntary blood donation following telephonic invitation, while 6.8% of them refused permanently. Approximately, 3.9% of the blood donors were willing to donate blood only when needed and 27.8% of them could not be contacted. CONCLUSION: Creating a database of voluntary donors with known phenotype, especially who lack very common antigens like "C" and "e" and are willing to become dedicated, regular voluntary donors for thalassemic patients can ensure timely administration of safe blood. One of the major challenges for this noble initiative was lack of awareness which can be circumvent effectively with proper counseling efforts.

Inhibition of Norovirus GII.4 Binding to HBGAs by Sargassum fusiforme Polysaccharide.

Norovirus (NoV) is the main pathogen that causes acute gastroenteritis and brings a heavy socio-economic burden worldwide. In this study, five polysaccharide fractions, labeled pSFP-1-5, were isolated and purified from Sargassum fusiforme (S. fusiforme). In vitro experiments demonstrated that pSFP-5 significantly prevented the binding of type A, B and H histo-blood group antigens (HBGAs) to NoV GII.4 virus-like particles (NoV GII.4 VLPs). In addition, in vivo experiments revealed that pSFP-5 was effective in reducing the accumulation of NoV in oysters, indicating that pSFP-5 could reduce the risk of NoV infection from oyster consumption. The results of transmission electron microscopy showed that the appearance of NoV GII.4 VLPs changed after pSFP-5 treatment, indicating that pSFP-5 may achieve antiviral ability by altering the morphological structure of the viral particles so that they could not bind to HBGAs. The results of this study indicate that pSFP-5 may be an effective anti-NoV substance and can be used as a potential anti-NoV drug component.

The current therapeutic cancer vaccines landscape in non-small cell lung cancer.

Currently, conventional immunotherapies for the treatment of non-small cell lung cancer (NSCLC) have low response rates and benefit only a minority of patients, particularly those with advanced disease, so novel therapeutic strategies are urgent deeded. Therapeutic cancer vaccines, a form of active immunotherapy, harness potential to activate the adaptive immune system against tumor cells via antigen cross-presentation. Cancer vaccines can establish enduring immune memory and guard against recurrences. Vaccine-induced tumor cell death prompts antigen epitope spreading, activating functional T cells and thereby sustaining a cancer-immunity cycle. The success of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rendered cancer vaccines a promising avenue, especially when combined with immunotherapy or chemoradiotherapy for NSCLC. This review delves into the intricate antitumor immune mechanisms underlying therapeutic cancer vaccines, enumerates the tumor antigen spectrum of NSCLC, discusses different cancer vaccines progress and summarizes relevant clinical trials. Additionally, we analyze the combination strategies, current limitations, and future prospects of cancer vaccines in NSCLC treatment, aiming to offer fresh insights for their clinical application in managing NSCLC. Overall, cancer vaccines offer promising potential for NSCLC treatment, particularly combining with chemoradiotherapy or immunotherapy could further improve survival in advanced patients. Exploring inhaled vaccines or prophylactic vaccines represents a crucial research avenue.

Multi-omics analysis of overexpressed tumor-associated proteins: gene expression, immunopeptide presentation, and antibody response in oropharyngeal squamous cell carcinoma, with a focus on cancer-testis antigens.

Introduction: The human leukocyte antigen complex (HLA) is essential for inducing specific immune responses to cancer by presenting tumor-associated peptides (TAP) to T cells. Overexpressed tumor associated antigens, mainly cancer-testis antigens (CTA), are outlined as essential targets for immunotherapy in oropharyngeal squamous cell carcinoma (OPSCC). This study assessed the degree to which presentation, gene expression, and antibody response (AR) of TAP, mainly CTA, are correlated in OPSCC patients to evaluate their potential as immunotherapy targets. Materials and methods: Snap-frozen tumor (NLigand/RNA=40), healthy mucosa (NRNA=6), and healthy tonsils (NLigand=5) samples were obtained. RNA-Seq was performed using Illumina HiSeq 2500/NovaSeq 6000 and whole exome sequencing (WES) utilizing NextSeq500. HLA ligands were isolated from tumor tissue using immunoaffinity purification, UHPLC, and analyzed by tandem MS. Antibodies were measured in serum (NAb=27) utilizing the KREX™ CT262 protein array. Data analysis focused on 312 proteins (KREX™ CT262 panel + overexpressed self-proteins). Results: 183 and 94 of HLA class I and II TAP were identified by comparative profiling with healthy tonsils. Genes from 26 TAP were overexpressed in tumors compared to healthy mucosa (LFC>1; FDR<0.05). Low concordance (r=0.25; p<0.0001) was found between upregulated mRNA and class I TAP. The specific mode of correlation of TAP was found to be dependent on clinical parameters. A lack of correlation was observed both between mRNA and class II TAP, as well as between class II tumor-unique TAP (TAP-U) presentation and antibody response (AR) levels. Discussion: This study demonstrates that focusing exclusively on gene transcript levels fails to capture the full extent of TAP presentation in OPSCC. Furthermore, our findings reveal that although CTA are presented at relatively low levels, a few CTA TAP-U show potential as targets for immunotherapy.

On-Demand Vaccine Production via Dock-and-Display of Biotinylated Antigens on Bacterial Extracellular Vesicles.

Engineered outer membrane vesicles (OMVs) derived from Gram-negative bacteria are a promising vaccine technology for developing immunity against diverse pathogens. However, antigen display on OMVs can be challenging to control and highly variable due to bottlenecks in protein expression and localization to the bacterial host cell's outer membrane, especially for bulky and complex antigens. Here, we describe methods related to a universal vaccine technology called AvidVax (avidin-based vaccine antigen crosslinking) for rapid and simplified assembly of antigens on the exterior of OMVs during vaccine development. The AvidVax platform involves remodeling the OMV surface with multiple copies of a synthetic antigen-binding protein (SNAP), which is an engineered fusion protein comprised of an outer membrane scaffold protein linked to a biotin-binding protein. The resulting SNAPs enable efficient decoration of OMVs with a molecularly diverse array of biotinylated subunit antigens, including globular and membrane proteins, glycans and glycoconjugates, haptens, lipids, nucleic acids, and short peptides. We detail the key steps in the AvidVax vaccine production pipeline including preparation and isolation of SNAP-OMVs, biotinylation and enrichment of vaccine antigens, and formulation and characterization of antigen-loaded SNAP-OMVs.

Lipidomic scanning of self-lipids identifies headless antigens for natural killer T cells.

To broadly measure the spectrum of cellular self-antigens for natural killer T cells (NKT), we developed a sensitive lipidomics system to analyze lipids trapped between CD1d and NKT T cell receptors (TCRs). We captured diverse antigen complexes formed in cells from natural endogenous lipids, with or without inducing endoplasmic reticulum (ER) stress. After separating protein complexes with no, low, or high CD1d-TCR interaction, we eluted lipids to establish the spectrum of self-lipids that facilitate this interaction. Although this unbiased approach identified fifteen molecules, they clustered into only two related groups: previously known phospholipid antigens and unexpected neutral lipid antigens. Mass spectrometry studies identified the neutral lipids as ceramides, deoxyceramides, and diacylglycerols, which can be considered headless lipids because they lack polar headgroups that usually form the TCR epitope. The crystal structure of the TCR-ceramide-CD1d complex showed how the missing headgroup allowed the TCR to predominantly contact CD1d, supporting a model of CD1d autoreactivity. Ceramide and related headless antigens mediated physiological TCR binding affinity, weak NKT cell responses, and tetramer binding to polyclonal human and mouse NKT cells. Ceramide and sphingomyelin are oppositely regulated components of the "sphingomyelin cycle" that are altered during apoptosis, transformation, and ER stress. Thus, the unique molecular link of ceramide to NKT cell response, along with the recent identification of sphingomyelin blockers of NKT cell activation, provide two mutually reinforcing links for NKT cell response to sterile cellular stress conditions.

Human Leukocyte Antigen and microRNAs as Key Orchestrators of Mild Cognitive Impairment and Alzheimer's Disease: A Systematic Review.

The expression of inflamma-miRs and human leukocyte antigen (HLA) haplotypes could indicate mild cognitive impairment (MCI) and Alzheimer's disease (AD). We used international databases to conduct a systematic review of studies on HLA variants and a meta-analysis of research on microRNAs (miRNAs). We aimed to analyze the discriminative value of HLA variants and miRNAs in MCI, AD and controls to evaluate the protective or causative effect of HLA in cognitive decline, establish the role of miRNAs as biomarkers for the early detection of AD, and find a possible link between miRNAs and HLA. Statistical analysis was conducted using Comprehensive Meta-analysis software, version 2.2.050 (Biostat Inc., Englewood, NJ, USA). The effect sizes were estimated by the logarithm base 2 of the fold change. The systematic review revealed that some HLA variants, such as HLA-B*4402, HLA-A*33:01, HLA-A*33:01, HLA-DPB1, HLA-DR15, HLA-DQB1*03:03, HLA-DQB1*06:01, HLA-DQB1*03:01, SNPs on HLA-DRB1/DQB1, and HLA-DQA1, predisposed to cognitive decline before the occurrence of AD, while HLA-A1*01, HLA-DRB1∗13:02, HLA-DRB1*04:04, and HLA-DRB1*04:01 demonstrated a protective role. The meta-analysis identified let-7 and miR-15/16 as biomarkers for the early detection of AD. The association between these two miRNA families and the HLA variants that predispose to AD could be used for the early screening and prevention of MCI.

HLA class-I polymorphisms among the Punjabi population of Pakistan: A comparative analysis with country's other ethnic groups.

The Punjabi population, constituting over 45 % of the country's total population, holds the highest prevalence in Pakistan. To understand their HLA genetics, we genotyped 389 Punjabi subjects for major Class-I loci using the PCR-SSO Luminex® method. Our study identified a total of 162 alleles, including 41 different HLA-A, 72 HLA-B, and 49 HLA-C alleles. The most common alleles included A*11:01 (14.6 %), A*01:01 (11.8 %), A*24:02 (11.3 %); B*40:06 (13.3 %), B*08:01 (10.9 %), B*51:01 (8.7 %); C*15:02 (15.5 %), C*07:02 (15.3 %), and C*04:01 (10.8 %). However, only locus B showed a significant deviation from HWE. The dominant Class I haplotype was A*24:02-B*40:06-C*15:02, followed by A*11:01-B*40:06-C*15:02, while significant LD was observed between all pairs of HLA loci. A distinct genetic makeup was observed in the Pakistani Punjabis as compared to Indian Punjabis, emphasizing the impact of the Indo-Pak partition and religious choices for marriage. In comparison to country's other ethnic groups, the Pakistani population exhibited 76 different alleles at a low field-resolution, with the Punjabi population having highest polymorphism. Phylogenetic analysis revealed that the Punjabi population is most closely related to the Sindhi population, while both populations sharing ancient connections with the Burusho population. These findings have significant implications for transplantation procedures, personalized medicine, disease susceptibility, and evolutionary studies.

Discovery of high-expressing lncRNA-derived sORFs as potential tumor-associated antigens in hepatocellular carcinoma.

BACKGROUND: This study is based on deep mining of Ribo-seq data for the identification of lncRNAs that have highly expressed sORFs in HCC. In this paper, dynamic prospects associated with sORFs acting as newly defined tumor-specific epitopes are discussed with possible improvement in strategies for tumor immunotherapy. OBJECTIVE: Using ribosome profiling to identify and characterize sORFs within lncRNAs in HCC, identify potential therapeutic targets and tumor-specific epitopes applicable for immunotherapy. METHODS: MetamORF performed the identification of sORFs with deep analysis of the data of ribosome profiling in lncRNAs associated with HCC. The translation efficiency in these molecules was estimated, and epitope prediction was done by pVACbind. Peptide search was done to check the presence of micropeptides translated from these identified sORFs. validated translational activity and identified potential epitopes. RESULTS: Higher translation efficiency was noted in the case of lncRNAs associated with HCC compared to normal tissues. Of particular note is ORF3418981, which results in the highest expression and has supporting experimental evidence at the protein level. Epitope prediction identified a putative epitope at the C-terminus of ORF3418981. CONCLUSIONS: This study uncovers the as-yet-unknown potential of lncRNA-derived sORFs as sources of tumor antigens, shifting the research focus from protein-coding genes to non-coding RNAs also in the HCC context. Moreover, this study highlights the contribution of a subset of lncRNAs, especially LINC00152, to the development of tumors and modulation of the immune response by its sORFs.

Role of Antibodies and Their Specificities in Atherosclerotic Cardiovascular Disease.

Atherosclerosis is a lipid-driven chronic inflammatory disease that is modulated by innate and adaptive immunity including humoral immunity. Importantly, antibody alterations achieved by genetic means or active and passive immunization strategies in preclinical studies can improve or aggravate atherosclerosis. Additionally, a wide range of epidemiological data demonstrate not only an association between the total levels of different antibody isotypes but also antibody levels targeting specific antigens with atherosclerotic cardiovascular disease. Here, we discuss the potential role of atherogenic dyslipidemia on the antibody repertoire and review potential antibody-mediated effector mechanisms involved in atherosclerosis development highlighting the major atherosclerosis-associated antigens that trigger antibody responses.

Germ cell tumors, cell surface markers, and the early search for human pluripotent stem cells.

Many strands of research by different groups, starting from teratocarcinomas in the laboratory mouse, later moving the corresponding human tumors, contributed to the isolation and description of human pluripotent stem cells (PSCs). In this review, I highlight the contributions from my own research, particularly at the Wistar Institute during the 1980s, when with my colleagues we characterized one of the first clonal lines of pluripotent human embryonal carcinoma (EC) cells, the stem cells of teratocarcinomas, and identified key features including cell surface antigen markers that have since found a place in the study and exploitation of human PSC. Much of this research depended upon close teamwork with colleagues, many in other laboratories, who contributed different expertise and experience. It was also often driven by circumstance and chance rather than pursuit of a grand design.

VacSol-ML(ESKAPE): Machine learning empowering vaccine antigen prediction for ESKAPE pathogens.

The ESKAPE family, comprising Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp., poses a significant global threat due to their heightened virulence and extensive antibiotic resistance. These pathogens contribute largely to the prevalence of nosocomial or hospital-acquired infections, resulting in high morbidity and mortality rates. To tackle this healthcare problem urgent measures are needed, including development of innovative vaccines and therapeutic strategies. Designing vaccines involves a complex and resource-intensive process of identifying protective antigens and potential vaccine candidates (PVCs) from pathogens. Reverse vaccinology (RV), an approach based on genomics, made this process more efficient by leveraging bioinformatics tools to identify potential vaccine candidates. In recent years, artificial intelligence and machine learning (ML) techniques has shown promise in enhancing the accuracy and efficiency of reverse vaccinology. This study introduces a supervised ML classification framework, to predict potential vaccine candidates specifically against ESKAPE pathogens. The model's training utilized biological and physicochemical properties from a dataset containing protective antigens and non-protective proteins of ESKAPE pathogens. Conventional autoencoders based strategy was employed for feature encoding and selection. During the training process, seven machine learning algorithms were trained and subjected to Stratified 5-fold Cross Validation. Random Forest and Logistic Regression exhibited best performance in various metrics including accuracy, precision, recall, WF1 score, and Area under the curve. An ensemble model was developed, to take collective strengths of both the algorithms. To assess efficacy of our final ensemble model, a high-quality benchmark dataset was employed. VacSol-ML(ESKAPE) demonstrated outstanding discrimination between protective vaccine candidates (PVCs) and non-protective antigens. VacSol-ML(ESKAPE), proves to be an invaluable tool in expediting vaccine development for these pathogens. Accessible to the public through both a web server and standalone version, it encourages collaborative research. The web-based and standalone tools are available at http://vacsolml.mgbio.tech/.

Efficacy of novel allogeneic cancer cells vaccine to treat colorectal cancer.

Colorectal cancer (CRC) remains a significant global health burden, emphasizing the need for innovative treatment strategies. 95% of the CRC population are microsatellite stable (MSS), insensitive to classical immunotherapies such as anti-PD-1; on the other hand, responders can become resistant and relapse. Recently, the use of cancer vaccines enhanced the immune response against tumor cells. In this context, we developed a therapeutic vaccine based on Stimulated Tumor Cells (STC) platform technology. This vaccine is composed of selected tumor cell lines stressed and haptenated in vitro to generate a factory of immunogenic cancer-related antigens validated by a proteomic cross analysis with patient's biopsies. This technology allows a multi-specific education of the immune system to target tumor cells harboring resistant clones. Here, we report safety and antitumor efficacy of the murine version of the STC vaccine on CT26 BALB/c CRC syngeneic murine models. We showed that one cell line (1CL)-based STC vaccine suppressed tumor growth and extended survival. In addition, three cell lines (3CL)-based STC vaccine significantly improves these parameters by presenting additional tumor-related antigens inducing a multi-specific anti-tumor immune response. Furthermore, proteomic analyses validated that the 3CL-based STC vaccine represents a wider quality range of tumor-related proteins than the 1CL-based STC vaccine covering key categories of tumor antigens related to tumor plasticity and treatment resistance. We also evaluated the efficacy of STC vaccine in an MC38 anti-PD-1 resistant syngeneic murine model. Vaccination with the 3CL-based STC vaccine significantly improved survival and showed a confirmed complete response with an antitumor activity carried by the increase of CD8+ lymphocyte T cells and M1 macrophage infiltration. These results demonstrate the potential of this technology to produce human vaccines for the treatment of patients with CRC.

Common RBC antigens in O type Tunisian blood donors and their importance in alloimmunization.

BACKGROUND: The presence of some red blood cell (RBC) antigens may affect the preference for using type O blood in emergency situations because they may induce complex or multiple alloimmunization in special circumstances. METHODS: A subgroup of 77 type O blood Tunisian donors were genotyped for 19 common blood alleles using the single specific primer-polymerase chain reaction method. The statistical analysis was done using HaploView software. RESULTS: The study showed the dominance of the alleles RH*5, KEL*2, FY*2, and CO*1 and the absence of the homozygous state of the KEL*1 and CO*2 alleles. Furthermore, a complete linkage disequilibrium between the RH*2/RH*4 and RH*3/RH*5 loci and the FY*Null/FY*Exp and FY*A/FY*B loci was detected. Additionally, it seems that sensitization to MNS:3, FY:1, and RH:3 may constitute a potential factor for alloimmunization after transfusion with O blood type units: the probabilities of simple alloimmunizations are 24.5 per 100, 18.5 per 100, and 18 per 100, respectively. Multiple alloimmunization against RH:1;KEL:1 or RH:1;KEL:1;RH:3 phenotypes may occur, with probabilities of 7 per 1000 and 2 per 1000, respectively. CONCLUSION: Some O-type RBC units may contain blood with very immunogenic phenotypes, the use of which in an emergency requires great caution because it can be a step towards subsequent alloimmunization.