Search

Sepsis is a syndrome associated with excessive inflammation. Since mortality from sepsis remains high, more laboratory research is needed to provide insight into more effective ways to use novel, potentially more beneficial agents in sepsis. We investigated the ex vivo immunomodulatory effect of a novel polyclonal Ab preparation, trimodulin, containing IgM (∼23%), IgA (∼21%) and IgG (∼56%). Using whole blood and purified PBMCs from healthy volunteers and patients with sepsis, various ex vivo investigations upon endotoxin challenge and pre- and post-trimodulin treatment were performed. Endotoxin-induced TNF-α secretion was noticeably lower with than without trimodulin, implying attenuation of the hyper-responsive state. Trimodulin also lowered TLR2, TLR4, CD11b and CD64 detection on LPS/lipoteichoic acid-stimulated monocytes. These responses were observed in cells from healthy volunteers only shortly after ex vivo endotoxin stimulation and in whole blood from patients with early-stage sepsis. Furthermore, trimodulin markedly reduced lymphocyte proliferation and release of pro- and anti-inflammatory cytokines, but did not affect phagocytosis or oxidative-burst activities of endoxin-stimulated cells. Thus, trimodulin mitigated monocyte and lymphocyte hyperinflammatory responses early after endotoxin exposure. Determining whether early in vivo administration of trimodulin will elicit similar positive immunomodulatory effects and offer a clinical benefit warrants investigation. [ABSTRACT FROM AUTHOR]

The response to neoadjuvant chemotherapy in breast cancer patients is usually assessed by pCR and RCB score. However, the prognostic value of these parameters is still in discussion. We showed recently that an epirubicin/docetaxel therapy is associated with an increase in the cell death marker high-mobility group box 1 protein ( HMGB1) in the circulation. Here, we investigate whether this increase correlates with the long-term outcome. Thirty-six early breast cancer patients under neoadjuvant epirubicin/docetaxel combination chemotherapy were included in this study. To determine the immediate effect of this treatment on HMGB1, we collected blood samples before and 24-96 h after the initial dose. This time course was then compared to the 5-year follow-up of the patients. HMGB1 levels varied before chemotherapy between 4.1 and 11.3 ng/mL and reacted differently in response to therapy. Some patients showed an increase while others did not show any changes. Therefore, we subdivided the patient collective into two groups: patients with an at least 1.1 ng/mL increase in HMGB1 and patients with smaller changes. The disease-free survival was longer in the HMGB1 increase group (56.2 months vs. 46.6 months), but this difference did not reach significance. The overall survival ( OS) was significantly better in patients with an increase in HMGB1 (log rank P = 0.021). These data suggest that an immediate increase in HMGB1 levels correlates with improved outcome in early breast cancer patients receiving neoadjuvant chemotherapy, and may be a valuable complementary biomarker for early estimation of prognosis. [ABSTRACT FROM AUTHOR]

The cyanobacterium Synechocystis sp. PCC 6803 is transformable at high efficiency and integrates DNA by homologous double recombination. However, several genetic mapping procedures depend on the ability to generate transformants even with very small amounts of added DNA. This study is aimed at optimizing the transformation efficiency at limiting concentrations of exogenous DNA. The transformation efficiency showed little sensitivity to experimental conditions. Transformation with circular plasmid DNA was found to be no more than 30% more efficient than with linearized plasmid DNA. The efficiency of transformation remained essentially the same in the presence of competing DNA, indicating that the capacity of DNA uptake by the cells is not limiting. The incubation time of cells with DNA before plating (0–8 h) affected the transformation efficiency by up to 3-fold. Only minor changes in the efficiency were observed as a function of the presence of a membrane filter on the plate or the presence of TAE or TBE gel buffer residues in the transformation mixture. However, transformability of the host strain of Synechocystis sp. PCC 6803 was increased by two orders of magnitude if the sll1354 gene encoding the exonuclease RecJ was deleted. Therefore, the transformation efficiency of Synechocystis sp. PCC 6803 with exogenous DNA appears to be determined primarily by intracellular processes such as the efficiency of DNA processing and homologous recombination. [Copyright &y& Elsevier]

Aim: The immune system plays a crucial role in the outcome of colorectal cancer. Systemic chemotherapies modulate the immune cell composition. Little is known about these changes in peritoneal metastasized colorectal cancer. Thus, we aimed to characterize local and systemic immune cells in the course of systemic chemotherapy., Methods: We included in total 20 patients with peritoneal metastasized colorectal cancer in our exploratory study. Initially, we investigated the peripheral blood cell distributions before and after systemic chemotherapy in a set of 11 retrospectively collected samples. Then, a prospective clinical cohort was set up to evaluate local and systemic immune cell distribution in detail (n = 9). Tumor tissue, peritoneal fluid, and peripheral blood were collected. The main immune cell subtypes were characterized using flow cytometry and immunohistochemistry, respectively., Results: Neutrophils and the neutrophil-to-lymphocyte ratio significantly declined in response to systemic chemotherapy while circulating T cells increased (CD8 + P = .015, CD4 + P = .041). In peritoneal fluid, we observed a decrease of CD25 + /FOXP3 + /CD4 + regulatory T cells (P = .049) without loss of their ability to produce interferon gamma. T-cell infiltration in the tumor microenvironment showed a considerable variability between patients. However, the number of tumor-infiltrating CD8 + lymphocytes was not significantly changed by the application of systemic chemotherapy. Neither tumor cells nor lymphocytes or macrophages showed noteworthy expression of PD1 or PD-L1., Conclusion: Our data show that immune cell distribution after systemic chemotherapy changes in peripheral blood. Interestingly, in peritoneal fluid only the inhibitory Treg population decreased and local T cells within peritoneal metastases remain unaffected. These data indicate little to no effect of systemic chemotherapy on the local immune system, supporting the need for new therapeutic options., Competing Interests: Conflict of Interest/Disclosure The authors confirm to have no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: We developed a novel intranasal influenza vaccine approach that is based on the construction of replication-deficient vaccine viruses that lack the entire NS1 gene (DeltaNS1 virus). We previously showed that these viruses undergo abortive replication in the respiratory tract of animals. The local release of type I interferons and other cytokines and chemokines in the upper respiratory tract may have a "self-adjuvant effect", in turn increasing vaccine immunogenicity. As a result, DeltaNS1 viruses elicit strong B- and T- cell mediated immune responses., Methodology/principal Findings: We applied this technology to the development of a pandemic H5N1 vaccine candidate. The vaccine virus was constructed by reverse genetics in Vero cells, as a 5:3 reassortant, encoding four proteins HA, NA, M1, and M2 of the A/Vietnam/1203/04 virus while the remaining genes were derived from IVR-116. The HA cleavage site was modified in a trypsin dependent manner, serving as the second attenuation factor in addition to the deleted NS1 gene. The vaccine candidate was able to grow in the Vero cells that were cultivated in a serum free medium to titers exceeding 8 log(10) TCID(50)/ml. The vaccine virus was replication deficient in interferon competent cells and did not lead to viral shedding in the vaccinated animals. The studies performed in three animal models confirmed the safety and immunogenicity of the vaccine. Intranasal immunization protected ferrets and mice from being infected with influenza H5 viruses of different clades. In a primate model (Macaca mulatta), one dose of vaccine delivered intranasally was sufficient for the induction of antibodies against homologous A/Vietnam/1203/04 and heterologous A/Indonesia/5/05 H5N1 strains., Conclusion/significance: Our findings show that intranasal immunization with the replication deficient H5N1 DeltaNS1 vaccine candidate is sufficient to induce a protective immune response against H5N1 viruses. This approach might be attractive as an alternative to conventional influenza vaccines. Clinical evaluation of DeltaNS1 pandemic and seasonal influenza vaccine candidates are currently in progress.

Immunotherapy with autologous dendritic cells (DCs) loaded with tumor lysate(s) from allogeneic tumor cell lines is a novel strategy to induce immune responses in cancer patients. We report on a pilot trial of autologous DCs pulsed with tumor cell lysate derived from allogeneic medullary thyroid carcinoma (MTC) cell lines in patients with metastatic MTC. The purpose of this study was to assess the safety, resulting immune responses and clinical activity of the DCs. DCs were injected into a groin lymph node at 3-week intervals. Monitoring included serial calcitonin tumor marker measurements, radiological imaging and immunological in vitro tests (T-cell interferon-gamma detection assay, T-cell cytotoxicity assay). Ten patients (median age 47 years, range 29-77) were enrolled. DC vaccinations were well-tolerated and safe. After a median follow-up of 11 months, (range 7-26), 3 (30%) of 10 patients had stable disease, while 7 (70%) of the patients progressed during treatment. In 2 patients with stable disease, calcitonin decreased below treatment levels, paralleled by a T-cell-mediated immune response. Notably, treatment with DCs pulsed with a combination of different tumor cell lysates was followed by a calcitonin decrease in 4 patients who had previously experienced a calcitonin increase during monotherapy with DCs pulsed with a single lysate. Allogeneic tumor cell lysate-based DC immunotherapy is well-tolerated and safe. Combined treatment with different tumor cell lysate-pulsed DCs increases the likelihood of a calcitonin tumor marker response and should therefore be preferred over monotherapy with DCs pulsed with a single lysate.