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Purpose: The carcinoembryonic antigen (CEA) is extensively expressed on the vast majority of colorectal, gastric, and pancreatic carcinomas, and, therefore, is a good target for tumor immunotherapy. CD4+ T-helper (Th) cells play a critical role in initiation, regulation, and maintenance of immune responses. In this study, we sought to identify Th epitopes derived from CEA which can induce CEA-specific Th responses. The combined application with cytotoxic T lymphocyte (CTL) epitopes would be more potent than tumor vaccines that primarily activate CTL alone. Methods. We utilized a combined approach of using a computer-based algorithm analysis TEPITOPE and in vitro biological analysis to identify Th epitopes in CEA. Results. Initial screening of healthy donors showed that all five predicted peptides derived from CEA could induce peptide-specific T-cell proliferation in vitro. We characterized these CEA epitopes by establishing and analyzing peptide-specific T-cell clones. It was shown that CD4+ T-cells specific for the CEA116epitope can recognize and respond to naturally processed CEA protein and CEA116 epitope can be promiscuously presented by commonly found major histocompatibility complex (MHC) alleles. Furthermore, it was demonstrated that immunization of human leukocyte antigen (HLA)-DR4 transgenic mice with CEA116 peptide elicited antigen-specific Th responses which can recognize the antigenic peptides derived from CEA protein and CEA-positive tumors. Conclusion. The MHC class II-restricted epitope CEA116 could be used in the design of peptide-based tumor vaccine against several common cancers expressing CEA. [ABSTRACT FROM AUTHOR]

Purpose: Systemic sclerosis (SSc) is a rare autoimmune disease associated with high morbidity and mortality. SSc treatment is still challenging, and evidence is scarce. In the last decades high-dose chemotherapy and autologous stem cell transplantation (HD-ASCT) has proven to be effective. However, treatment related morbidity and mortality (TRM) are high. We conducted a retrospective, single-center analysis of SSc patients following HD-ASCT focusing on TRM and risk factors. Methods: 32 patients who underwent HD-ASCT at our hospital between June 2000 and September 2020 were included. Clinical characteristics were evaluated based on chart review before and after HD-ASCT. Analyses focused on overall survival (OS), TRM, and response to HD-ASCT. Results: Median OS was 81 months (range 0–243). Within one year, 20 of 32 (76.9%) patients responded to HD-ASCT. Overall, 6 patients (18.8%) died in the context of HD-ASCT. Patients with subjective response to HD-ASCT (p = 0.024) and those with shorter time to platelet engraftment (p = 0.047) had significantly longer OS. Impaired renal function, age at HD-ASCT ≥ 55, disease duration < 12 months, high Hematopoietic cell transplantation-specific comorbidity index (HCT-CI) and Charlton Comorbidity Index (CCI) scores were associated with higher TRM. Patients receiving conditioning chemotherapy with thiotepa needed longer time for neutrophil (p = 0.035) and platelet engraftment (p = 0.021). Conclusion: This study confirms the efficacy of HD-ASCT for patients with SSc in a single center real-world setting. High TRM is still a challenge. However, TRM could be reduced by exclusion of high-risk patients and attention to prognostic parameters and scores as suggested in this study. [ABSTRACT FROM AUTHOR]

Primary lymphomatoid granulomatosis of the CNS (CNS-LG) is a rare lymphoid neoplasia associated Epstein–Barr Virus (EBV) and often accompanied by immunodeficiencies. No treatment standards have been defined yet. However, due to often devastating neurologic sequelae and based on similarities to diffuse large B-cell lymphoma, curative treatment requires intensive therapy protocols resembling protocols applied in CNS lymphoma. Here, the clinical courses and treatments of four primary CNS-LG patients in analogy to aggressive CNS-lymphomas including methotrexate, thiotepa, cytarabine, carmustine, and rituximab are presented. This is the first report on high-dose chemotherapy with CNS-directed drugs and autologous blood stem cell transplantation in primary CNS-LG. [ABSTRACT FROM AUTHOR]

Chimeric antigen receptors (CARs) have improved cancer immunotherapy in recent years. Immune cells, such as Natural killer cells (NK-cells) or T cells, are used as effector cells in CAR-therapy. NK92-cells, a cell line with known cytotoxic activity, are of particular interest in CAR-therapy since culturing conditions are simple and anti-tumor efficacy combined with a manageable safety profile was proven in clinical trials. The major pathways of immune effector cells, including NK92-cells, to mediate cytotoxicity, are the perforin/granzyme and the death-receptor pathway. Detailed knowledge of CAR-effector cells' cytotoxic mechanisms is essential to unravel resistance mechanisms, which potentially arise by resistance against apoptosis-inducing signaling. Since mutations in apoptosis pathways are frequent in lymphoma, the impact on CAR-mediated cytotoxicity is of clinical interest. In this study, knockout models of CD19-CAR-NK92 cells were designed, to investigate cytotoxic pathways in vitro. Knockout of perforin 1 (Prf1) and subsequent abrogation of the perforin/granzyme pathway dramatically reduced the cytotoxicity of CD19-CAR-NK92 cells. In contrast, knockout of FasL and inhibition of TRAIL (tumor necrosis factor-related apoptosis-inducing ligands) did not impair cytotoxicity in most conditions. In conclusion, these results indicate the perforin/granzyme pathway as the major pathway to mediate cytotoxicity in CD19-CAR-NK92 cells. [ABSTRACT FROM AUTHOR]

Purpose: Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome emerging from a deregulated immune response due to various triggers. In adults, systematic data are sparse, which is why recommendations on diagnosis and management have been adopted from pediatric guidelines. A nationwide clinical registry with associated consulting service as collaborative initiative of HLH-specialized pediatricians and hematologists was initiated to better characterize HLH in adults. Methods: Patients with proven or suspected HLH were registered by 44 institutions. Both HLH-2004 diagnostic criteria and the HScore (www.saintantoine.aphp.fr/score/) were used to confirm HLH diagnosis. Data referring to underlying disease, treatment, outcome, clinical presentation and laboratory findings were recorded. Results: The study included 137 patients and provides the first systematic data on adult HLH in Germany. Median age was 50 years with a wide range (17–87 years), 87 patients (63.5%) were male. Most common triggering diseases were infections in 61 patients (44.5%) and malignancies in 48 patients (35%). Virtually all patients had elevated ferritin concentrations, and 74% had peak concentrations greater than 10,000 µg/l. At time of analysis, 67 of 131 patients (51%) had died. Patients with malignancy-associated HLH had the shortest median survival (160 days), however no statistically significant difference between subgroups was observed (p = 0.077). Platelets under 20*109/l and low albumin concentrations (< 20 g/l) were associated with poor overall and 30-day survival. Conclusion: Close multidisciplinary case consultation and cooperation is mandatory when treating adult HLH patients. Early contact with reference centers is recommended, especially in relapsing or refractory disease. [ABSTRACT FROM AUTHOR]

Background and Objectives: Up to now the diagnosis of early stage cholangiocarcinoma (CC) has remained difficult, with low sensitivities reported for current diagnostic methods. Based on recent promising findings about circulating U2 small nuclear RNA fragments (RNU2-1f) as novel blood-based biomarkers for pancreatic and colorectal adenocarcinoma, we studied the utility of RNU2-1f as a diagnostic marker of CC in bile fluid. Methods: Bile fluid was collected from patients with CC ( n = 12), controls (patients with choledocholithiasis) ( n = 11) and with primary sclerosing cholangitis (PSC; n = 11). RNU2-1f levels were measured by real-time polymerase chain reaction normalized to cel-54. Results: Measurement of RNU2-1f levels in bile fluids enabled the differentiation of patients with CC from controls in all cases. Furthermore, RNU2-1f levels in bile fluids of patients with CC were significantly higher than in patients with PSC, resulting in a receiver-operating characteristic curve area of 0.856, with sensitivity of 67 % and specificity of 91 %. Conclusions: Our data suggest that the measurement of RNU2-1 fragments detected in the bile fluid can be used as a diagnostic marker for CC and should be included in future prospective diagnostic studies for this disease entity. [ABSTRACT FROM AUTHOR]

The present study assessed the role of adenoviral vector-mediated wild-type p53 gene transfer in B lymphoma cells. Deficiency of p53-mediated cell death is common in human cancer contributing to both tumorigenesis and chemoresistance. Lymphoma cells are being considered as suitable targets for gene therapy protocols. Recently, we reported an adenoviral protocol leading to highly efficient gene transfer to B lymphoma celIs. All lymphoma cell lines (n=5) tested here showed mutations in the p53 gene locus. The aim of this work was to transduce lymphoma cells with the wild-type p53 gene. Using this protocol, 88% of Raji, 75% of Daudi, and 45% of OCI-Ly8-LAM53 celIs were transfected with the reporter gene green fluorescent protein at a muItiplicity of infection of 200. The expression of green fluorescent protein in CA46 and BL41 cells was 27% and 42%, respectively. At this multiplicity of infection, growth characteristics of lymphoma cell lines were not changed significantly. In contrast, cells transduced with wild-type p53 gene showed an inhibition of proliferation as well as an increase in apoptosis. Cell loss by apoptosis after p53 gene transfer was up to 40% as compared to transduction with an irrelevant vector. In addition, we determined the effects of DNA damage produced by the DNA topoisomerase II inhibitor etoposide on wild-type p53 transfected lymphoma celIs. In Ad-p53-transfected Raji celIs, treatment with the drug resulted in a marked increase of cell loss in comparison to Ad-β-Gal-transfected cells (45% vs. 77%). Interestingly, performing cytotoxicity studies, we could show an increased sensitivity of Raji and Daudi cells against immunological effector cells. In conclusion, transduction of wild-type p53 into lymphoma cells expressing mutated p53 was efficient and led to inhibition of proliferation and increase in apoptotic rate in some cell lines dependent on p53 mutation. This protocol shouId have an impact on the use of lymphoma cells in cancer... [ABSTRACT FROM AUTHOR]

Dendritic cells (DCs) are the major antigen-presenting cells. They are able to present tumor antigens to immunologic effector cells. MHC class II molecules on DC surfaces play an important role in priming effector cells against tumor cells and their antigens. The transactivator CIITA (MHC class II transactivator) is a non–DNA-binding transactivator, which regulates the expression of MHC class II, HLA-DM, and invariant chain and behaves as a master controller of constitutive and inducible MHC class II gene activation. Here, we transfected DCs with the CIITA gene using a novel transfection technique. The vector system consisted of a plasmid bound to an adenovirus via poly-l-lysine, which is covalently bound to a UV-irradiated adenovirus. After transfection, expression of MHC class II on DCs increased from 27% to 75% on day 2 after transfection. Transfected DCs were co-cultured with immunologic effector cells. Cytotoxicity of effector cells against tumor cells increased after co-culture with transfected DCs to 63% compared to 15% with effector cells co-cultured with irrelevantly transfected DCs (P=.037). This effect was dependent on the timing and period of co-culture. In conclusion, transfection of DCs led to an increase in antitumoral immunostimulatory capacity of DCs. We can further conclude that DCs could be efficiently transfected with the CIITA gene. Transfection of DCs led to an increase in antitumoral immunostimulatory capacity of DCs and may have a major impact on immunotherapeutic protocols for patients with cancer. Cancer Gene Therapy (2001) 8, 211–219 [ABSTRACT FROM AUTHOR]