Increase In IL-10 Production Research Articles

The Role of Immune Defense in Serratia marcescens Nosocomial Infections

Developing resistance mechanisms leads to various nosocomial infections caused by opportunistic bacteria. Serratia marcescens are well known to be opportunistic and are equipped with an armory of virulence factors against host immune response. The study aims to detect the immune defense in patients infected with multidrug-resistant S. marcescens. The study includes 132 clinical samples, including burn, wound, otitis media, and urinary tract infection (UTI) at several hospitals in Baghdad, Iraq. All isolates are identified by cultivation on MacConkey agar, nutrient agar, and blood agar, followed by biochemical tests and assessment with the VITEK 2 compact system. The isolates are tested for antibiotic susceptibility tests, interleukin-12 (IL12) levels, neutrophil ability to phagocytosis, and complement C3 and C4 levels. Out of 120 positive cultures, six isolates are identified as S. marcescens. The urine samples are the most isolated source and a higher level of antibiotic resistance was noticed in ampicillin and cefotaxime (100%), whereas a lower level is in imipenem. Stimulation (p ꞊ 0.005) provided a significant increase in IL-12 production. The infection with the S. marcescens stimulated the neutrophil’s phagocytosis process compared with the control. The interplay role of virulence factors in S. marcescens influences its pathogenesis, antibiotic resistance, and immune response, particularly involving neutrophils and IL-12. Understanding these interactions is crucial for developing effective therapeutic strategies.

ANTI-OXIDANT, ANTI-BACTERIAL, AND ANTI-INFLAMMATORY ACTIVITY OF Scutellaria baicalensis ROOT SUPERCRITICAL FLUID EXTRACTS

Scutellaria baicalensis (S. baicalensis) root extract has been used for a long time in Oriental medicine and the cosmetics industry due to its natural anti-oxidant properties in disease treatment. However, comprehensive studies comparing the physiological activities of different S. baicalensis root extracts are lacking. Specifically, there is a need to compare S. baicalensis root hydrothermal extract (SBHE), S. baicalensis root 75% ethyl alcohol extract (SBAE), and S. baicalensis root supercritical fluid extracts (SBSEs) simultaneously. In this study, we extracted S. baicalensis roots using three different methods: hydrothermal, 75% ethyl alcohol, and supercritical fluid extraction. We then evaluated their radical scavenging activities, SOD-like activity, anti-bacterial activities, and the production of inflammatory factors. Among the extracts tested, the S. baicalensis root supercritical fluid 35°C extract (SBSE35) exhibited superior overall physiological activities. Notably, only the SBSEs demonstrated anti-bacterial activity against Staphylococcus aureus, whereas SBHE and SBAE did not. SBHE and SBAE increased interleukin (IL)-6 levels (p ≤ 0.05). Additionally, SBHE and SBAE showed a slight decrease in IL-8 at low concentrations, but an increase in IL-8 production in a concentration-dependent manner. In contrast, SBSE35 significantly reduced both IL-6 and IL-8 levels (p ≤ 0.05). These findings suggest that SBSE35 has greater potential for improving human health in the cosmetics and pharmaceutical fields. Keywords: Scutellaria baicalensis root; supercritical fluid extraction; anti-oxidant; anti-bacterial; anti-inflammation

Immunotherapeutic potential of collagen V oral administration in mBSA/CFA-induced arthritis.

We hypothesized that after synovial injury, collagen V (Col V) expose occult antigens, and Col V autoantibodies develop, indicating the loss of immune tolerance against this molecule, thus leading to damage to mesenchymal-derived cells as well as the extracellular matrix in experimental arthritis. Thus, the present study investigated the effects of oral administration of Col V on the synovium after the development of inflammation in mBSA/CFA-induced arthritis. After fourteen days of intraarticular administration of mBSA, 10 male Lewis rats were orally administered Col V (500 μg/300 μL) diluted in 0.01 N acetic acid (IA-Col V group). The arthritic group (IA group, n = 10) received only intraarticular mBSA. An intra-articular saline injection (20 μL) was given to the control group (CT-Col V, n = 5). IA group presented damaged synovia, the expansion of the extracellular matrix by cellular infiltrate, which was characterized by T and B lymphocytes, and fibroblastic infiltration. In contrast, after Col V oral immunotherapy IA-Col V group showed a significant reduction in synovial inflammation and intense expression of IL-10+ and FoxP3+ cells, in addition to a reduction in Col V and an increase in Col I in the synovia compared to those in the IA group. Furthermore, an increase in IL-10 production was detected after IA-Col V group spleen cell stimulation with Col V in vitro. PET imaging did not differ between the groups. The evaluation of oral treatment with Col V, after mBSA/CFA-induced arthritis in rats, protects against inflammation and reduces synovial tissue damage, through modulation of the synovial matrix, showing an immunotherapeutic potential in inhibiting synovitis.

Absence of PD-L1 signaling hinders macrophage defense against Mycobacterium tuberculosis via upregulating STAT3/IL-6 pathway

The blockade of programmed death-ligand 1 (PD-L1) pathway has been clinically used in cancer immunotherapy, while its effects on infectious diseases remain elusive. Roles of PD-L1 signaling in the macrophage-mediated innate immune defense against M.tb is unclear. In this study, the outcomes of tuberculosis (TB) in wild-type (WT) mice treated with anti-PD-1/PD-L1 therapy and macrophage-specific Pdl1-knockout (Pdl1ΔΜΦ) mice were compared. Treatment with anti-PD-L1 or anti-PD-1 benefited protection against M.tb infection in WT mice, while Pdl1ΔΜΦ mice exhibited the increased susceptibility to M.tb infection. Mechanistically, the absence of PD-L1 signaling impaired M.tb killing by macrophages. Furthermore, elevated STAT3 activation was found in PD-L1-deficient macrophages, leading to increased interleukin (IL)-6 production and reduced inducible nitric oxide synthase (iNOS) expression. Inhibiting STAT3 phosphorylation partially impeded the increase in IL-6 production and restored iNOS expression in these PD-L1-deficient cells. These findings provide valuable insights into the complexity and mechanisms underlying anti-PD-L1 therapy in the context of tuberculosis.

Relevance of Thymic Stromal Lymphopoietin on the Pathogenesis of Glioblastoma: Role of the Neutrophil

Glioblastoma multiforme (GBM) is the most predominant and malignant primary brain tumor in adults. Thymic stromal lymphopoietin (TSLP), a cytokine primarily generated by activated epithelial cells, has recently garnered attention in cancer research. This study was aimed to elucidate the significance of TSLP in GBM cells and its interplay with the immune system, particularly focused on granulocyte neutrophils. Our results demonstrate that the tumor produces TSLP when stimulated with epidermal growth factor (EGF) in both the U251 cell line and the GBM biopsy (GBM-b). The relevance of the TSLP function was evaluated using a 3D spheroid model. Spheroids exhibited increased diameter, volume, and proliferation. In addition, TSLP promoted the generation of satellites surrounding the main spheroids and inhibited apoptosis in U251 treated with temozolomide (TMZ). Additionally, the co-culture of polymorphonuclear (PMN) cells from healthy donors with the U251 cell line in the presence of TSLP showed a reduction in apoptosis and an increase in IL-8 production. TSLP directly inhibited apoptosis in PMN from GBM patients (PMN-p). Interestingly, the vascular endothelial growth factor (VEGF) production was elevated in PMN-p compared with PMN from healthy donors. Under these conditions, TSLP also increased VEGF production, in PMN from healthy donors. Moreover, TSLP upregulated programed death-ligand 1 (PDL-1) expression in PMN cultured with U251. On the other hand, according to our results, the analysis of RNA-seq datasets from Illumina HiSeq 2000 sequencing platform performed with TIMER2.0 webserver demonstrated that the combination of TSLP with neutrophils decreases the survival of the patient. In conclusion, our results position TSLP as a possible new growth factor in GBM and indicate its modulation of the tumor microenvironment, particularly through its interaction with PMN.Graphical Protumoral activity of TSLP. Neutrophils (derived from GBM patients) and GBM cells (under EGF stimulus) not only produce TSLP but also express its receptor. TSLP induces PDL1 expression and decreases apoptosis on both GBM cells and neutrophils. TSLP also increases proliferation and satellite development on GBM cells, whereas favors more neutrophil infiltration by increasing IL8 production.

Secretome of adipose derived-mesenchymal stem cells reduces the Vibrio cholerae attachment to Caco-2 cells and subsequent inflammatory responses.

Mesenchymal Stem Cells (MSCs) can repair gastrointestinal tract damage. The Secretome of MSCs has a high capacity to inhibit bacterial colonization and the subsequent inflammatory responses of Vibrio cholerae. The Caco-2 cells were treated with adipose-derived MSCs (AD-MSCs) secretome and then infected with V. cholerae. Subsequently, the bacterial attachment and invasion, cholera toxin gene expression, PGE2 and IL-6 secretion, TNF-α, IL-1β, and IL-8 expression, and apoptosis of Caco-2 cells were evaluated. The secretome of AD-MSCs significantly reduced the V. cholerae attachment and internalization on Caco-2 epithelial cells (P<0.0001). The cholera toxin (Ctx-B) gene expression (FR=4.56 ± 0.66) and PGE2 production (P=0.0007) were also significantly reduced. The production of NO and TNF-α, IL-1β, and IL-8 pro-inflammatory cytokines were significantly (P<0.05) reduced in exposure to the secretome of AD-MSCs. Secretome also improved a significant 81.33% increase in IL-6 production (128.1 ± 37.6 pg/mL) and showed a 12.36% significant decrease in epithelial cell apoptosis (P< 0.0001) after exposure to V. cholerae. The secretome of AD-MSCs can play a critical role in inhibiting bacterial colonization, and subsequent inflammatory responses, and maintaining the integrity of the epithelial barrier. The secretome may be effective in the prevention of hypovolemic shock.

Does milk prevent or promote inflammation? Insights from in vitro assays

Milk is widely consumed worldwide due to its high nutritional value, having possible protection against infections and anti-inflammatory activity. Conversely, milk's vast microbiota reduces its shelf life and can pose risks to human health. Milk processing can introduce changes to its components, leading to speculation about its inflammatory potential. Chronic inflammation is associated with the development of a variety of metabolic, autoimmune, and degenerative diseases, being essential to understand the role of food in its etiology. This study aimed to investigate processed milk samples for their potential to modulate inflammatory responses in an intestinal in vitro model, contributing to the current debate about the effects of processed milk's consumption. Raw, pasteurized, and ultra-high temperature (UHT) homogenized milk were subjected to an in vitro simulated digestion process and human colorectal adenocarcinoma cells (Caco-2) and Abelson murine leukemia macrophages (Raw 264.7) were cultivated in vitro and challenged with milk samples from before and after digestion process. Post-digestion, pasteurized milk decreased the production of IL-8 in 59%, indicating an anti-inflammatory activity. UHT homogenized milk increased the production of assessed cytokines up to 238%, showing a pro-inflammatory response. Raw milk presented a 321% increase in IL-6 production, indicating a pro-inflammatory effect, as observed in processed milk samples. These new findings suggest that consumption of raw milk can be potentially inflammatory due to its vast microbiota, in addition to the well-known risks of its consumption and, that processed milk can prevent or promote inflammation according to the type of processing to which it was submitted.

Siglec-F+ neutrophils in the spleen induce immunosuppression following acute infection.

Background: The mechanisms underlying the increased mortality of secondary infections during the immunosuppressive phase of sepsis remain elusive. Objectives: We sought to investigate the role of Siglec-F+ neutrophils on splenic T lymphocytes in the immunosuppressed phase of sepsis and on secondary infection in PICS mice, and to elucidate the underlying mechanisms. Methods: We established a mouse model of sepsis-induced immunosuppression followed by secondary infection with LPS or E. coli. The main manifestation of immunosuppression is the functional exhaustion of splenic T lymphocytes. Treg depletion reagent Anti-IL-2, IL-10 blocker Anti-IL-10R, macrophage depletion reagent Liposomes, neutrophil depletion reagent Anti-Ly6G, neutrophil migration inhibitor SB225002, Siglec-F depletion reagent Anti-Siglec-F are all used on PICS mice. The function of neutrophil subsets was investigated by adoptive transplantation and the experiments in vitro. Results: Compared to other organs, we observed a significant reduction in pro-inflammatory cytokines in the spleen, accompanied by a marked increase in IL-10 production, primarily by infiltrating neutrophils. These infiltrating neutrophils in the spleen during the immunosuppressive phase of sepsis undergo phenotypic change in the local microenvironment, exhibiting high expression of neutrophil biomarkers such as Siglec-F, Ly6G, and Siglec-E. Depletion of neutrophils or specifically targeting Siglec-F leads to enhance the function of T lymphocytes and a notable improvement in the survival of mice with secondary infections. Conclusions: We identified Siglec-F+ neutrophils as the primary producers of IL-10, which significantly contributed to T lymphocyte suppression represents a novel finding with potential therapeutic implications.

IL-2 produced by HBV-specific T cells as a biomarker of viral control and predictor of response to PD-1 therapy across clinical phases of chronic hepatitis B.

There are no immunological biomarkers that predict control of chronic hepatitis B (CHB). The lack of immune biomarkers raises concerns for therapies targeting PD-1/PD-L1 because they have the potential for immune-related adverse events. Defining specific immune functions associated with control of HBV replication could identify patients likely to respond to anti-PD-1/PD-L1 therapies and achieve a durable functional cure. We enrolled immunotolerant, HBeAg+ immune-active (IA+), HBeAg- immune-active (IA-), inactive carriers, and functionally cured patients to test ex vivo PD-1 blockade on HBV-specific T cell functionality. Peripheral blood mononuclear cells were stimulated with overlapping peptides covering HBV proteins +/-α-PD-1 blockade. Functional T cells were measured using a 2-color FluoroSpot assay for interferon-γ and IL-2. Ex vivo functional restoration was compared to the interferon response capacity assay, which predicts overall survival in cancer patients receiving checkpoint inhibitors. Ex vivo interferon-γ+ responses did not differ across clinical phases. IL-2+ responses were significantly higher in patients with better viral control and preferentially restored with PD-1 blockade. Inactive carrier patients displayed the greatest increase in IL-2 production, which was dominated by CD4 T cell and response to the HBcAg. The interferon response capacity assay significantly correlated with the degree of HBV-specific T cell restoration. IL-2 production was associated with better HBV control and superior to interferon-γ as a marker of T cell restoration following ex vivo PD-1 blockade. Our study suggests that responsiveness to ex vivo PD-1 blockade, or the interferon response capacity assay, may support stratification for α-PD-1 therapies.

Crosstalk within peripheral blood mononuclear cells mediates anti-inflammatory effects of n-3 PUFA-rich lipid emulsions in parenteral nutrition

Parenteral nutrition (PN) rich in n-6 and n-3 long-chain fatty acids is used in clinical practice for nourishing patients who are unable to receive adequate nutrition through their digestive systems. In this study, we compare the effect on inflammation of the commonly used lipid emulsions Omegaven (n-3-rich) and Intralipid (n-6-rich) in human peripheral blood mononuclear cells (PBMCs). PBMCs were treated with different doses of n-3-rich Omegaven and n-6-rich Intralipid and the immune cells were characterized by flow cytometry. We show that incubation of PBMCs with n-3-rich Omegaven leads to an increase in expression of CD1d and CD86 in CD14+monocytes. At the same time, an increased number of NKT cells expressing cytotoxic T cell antigen 4 is observed, suggesting immunological synapse formation. Both CD14+monocytes and NKT cells showed an increase in IL-10 production and a reduction in the pro-inflammatory cytokines IFN-γ, TNF-α, and IL-4, which led to an increase in the number of FOXP3+T regulatory cells. In addition, we show that n-3-rich Omegaven reduces the expression of TNFα, IFNγ and IL-4 in CD4+T and CD8+T cells independent of the presented interaction between CD14+monocytes and NKT cells. The described mechanism of n-3 rich lipid emulsions was confirmed in PBMCs from patients with inflammatory bowel disease but not in colorectal cancer patients which seem to lack the interaction between CD14+monocytes and NKT cells. These results show a mechanism for the beneficial effect of the n-3-rich Omegaven in patients with inflammatory conditions but questions its use in patients with cancer. Hence, our results may assist in choosing the best lipid emulsion for patients who require PN.

Endometrial cell‑derived exosomes facilitate the development of adenomyosis via the IL‑6/JAK2/STAT3 pathway.

Interleukin (IL)-6 upregulation is involved in the pathogenesis of adenomyosis, but the underlying mechanism remains to be elucidated. Exosomes mediate intercellular communication, therefore the present study investigated whether endometrial cell-derived exosomes mediated the crosstalk between the endometrium and the myometrium via IL-6 signaling. Primary adenomyotic myometrial (AM) cells and eutopic endometrial cells were isolated from patients with adenomyosis. Exosomes were obtained from endometrial cells and incubated with AM cells in the presence or absence of tocilizumab (an IL-6 inhibitor). MTT, flow cytometry and wound-healing assays were performed to examine AM cell proliferation, apoptosis, cell cycle distribution and migration. Western blotting and reverse transcription-quantitative PCR were conducted to determine the expression of the IL-6/Janus kinase 2 (JAK2)/STAT3 pathway proteins. Incubation with endometrial cell exosomes suppressed cell apoptosis of AM cells compared with controls, accompanied by increases in IL-6 production and JAK2/STAT3 phosphorylation. Endometrial cell exosomes promoted cell proliferation, increased the percentage of S-phase cells and enhanced the migration of AM cells. These effects were completely reversed by tocilizumab, along with substantial decreases in IL-6 production and JAK2/STAT3 phosphorylation. Endometrial cell-derived exosomes promote cell proliferation, migration and cell cycle transition of AM cells through IL-6/JAK2/STAT3 activation, facilitating the development of adenomyosis by mediating the crosstalk between the endometrium and the myometrium, and IL-6 targeted therapy could be a complementary approach against adenomyosis.

Maltol has anti-cancer effects via modulating PD-L1 signaling pathway in B16F10 cells.

Introduction: Among skin cancers, melanoma has a high mortality rate. Recent advances in immunotherapy, particularly through immune checkpoint modulation, have improved the clinical treatment of melanoma. Maltol has various bioactivities, including anti-oxidant and anti-inflammatory properties, but the anti-melanoma property of maltol remains underexplored. The aim of this work is to explore the anti-melanoma potential of maltol through regulating immune checkpoints. Methods: The immune checkpoint PD-L1 was analyzed using qPCR, immunoblots, and immunofluorescence. Melanoma sensitivity towards T cells was investigated via cytotoxicity, cell viability, and IL-2 assays employing CTLL-2 cells. Results: Maltol was found to reduce melanin contents, tyrosinase activity, and expression levels of tyrosinase and tyrosinase-related protein 1. Additionally, maltol suppressed the proliferative capacity of B16F10 and induced cell cycle arrest. Maltol increased apoptotic rates by elevating cleaved caspase-3 and PARP. The co-treatment with maltol and cisplatin revealed a synergistic effect on inhibiting growth and promoting apoptosis. Maltol suppressed IFN-γ-induced PD-L1 and cisplatin-upregulated PD-L1 by attenuating STAT1 phosphorylation, thereby enhancing cisplatin's cytotoxicity against B16F10. Maltol augmented sensitivity to CTLL-2 cell-regulated melanoma destruction, leading to an increase in IL-2 production. Discussion: These findings demonstrate that maltol restricts melanoma growth through the downregulation of PD-L1 and elicits T cell-mediated anti-cancer responses, overcoming PD-L1-mediated immunotherapy resistance of cisplatin. Therefore, maltol can be considered as an effective therapeutic agent against melanoma.

Influence of microbial polyamines on the IL-10 production by peripheral blood leukocytes of healthy donors

As is known, bacterial polyamines, which include cadaverine and putrescine, are capable of influencing the activity of immunocompetent cells in many ways. In particular, this situation is observed in long-term inflammatory diseases, especially with intensive reproduction of microorganisms capable of producing polyamines. It is of interest to study the production of one of the main anti-inflammatory cytokines, IL-10, under the influence of bacterial polyamines. For research, a population of mononuclear leukocytes was isolated from the peripheral blood of healthy donors by gradient centrifugation. The cell suspension was placed in a round-bottomed plates with preliminarily added polyamines at concentrations of 5, 25, 50, 75, and 100 mmol/L. Wells not containing polyamines were used as a control. After incubation for 72 h at 37 °C and 5% CO2, the supernatants were harvested and used to determine the concentration of IL-10. We used a kit for determining the concentration of IL-10 using the enzyme immunoassay method (Russia). Statistical analysis was performed using the Statistica 6.0 software package. In the case of a distribution close to normal, Student’s t-test was used; in the rest, the Mann–Whitney test was used to assess the significance of differences. Studies have shown that leukocytes in the presence of concanavalin A produce IL-10 at a concentration of 17.13±6.08 pg/mL. It has been established that under the influence of polyamines of bacterial origin, the production of IL-10 is enhanced only if putrescine and cadaverine are at concentrations of 50 mmol/L and higher. At low concentrations of polyamines, no significant increase in IL-10 production was detected. Since IL-10 is an anti- inflammatory cytokine, for which the analgesic effect is also known, it should be expected that with an increase in its concentration in the focus of invasion of opportunistic bacteria, the inflammatory process will develop latently, when the symptoms are mild. In general, it can be expected that polyamine-producing bacteria will contribute to the maintenance of few symptomatic inflammation.

117 The Impact of Cell Passage Number on Elucidating Toxicological Mechanisms in Vitro

Abstract Cell passage number is of high importance in experimental design and can cause biochemical, genetic, and/or morphological changes to a cell. This project aimed to understand the impact of increasing cell passage number on the structure and function of epithelial cells from different organs. Two epithelial cell types were studied, NCI-H441 lung cells (type II alveolar cells), and HepG2 liver cells. Predefined ranges of 11-20, 21-30, 31-40, and 41-50 were studied. Cells were exposed to 1µg/mL tumour necrosis factor α (TNFα) and 15µM hydrogen peroxide (H2O2) via submerged or quasi-air liquid interface, according to GIVIMP guidelines. Endpoints tests included cytotoxicity (lactate dehydrogenase (LDH) release), cell death (BCL2, BAX, FAS), (pro-) inflammatory mediators (IL6 &amp; IL8), oxidative stress (SOD1) and genetic toxicology (DNA damage (p21 &amp; p53)). In addition, confocal microscopy was used to observe any changes to cell morphology. Preliminary data indicates the NCI-H441 epithelial cell passage range has an effect on the secretion of (pro-)inflammatory mediators, with an increase in IL8 and IL6 in higher passage ranges (41-50) compared to lower passage ranges (11-20) when stimulated with TNFα as a positive control. In HepG2 cells there is also an increase in IL8 production across passage range, however, it is considerably less than NCI-H441 cells. In addition, IL6 production in HepG2 cells was negligible across all passage ranges. LDH assay showed minimal variation between cell type and passage number. Data obtained suggests passage range, depending on cell type, has an influence on the effect level of the end point measured.

Immunopathogenesis of Campylobacter jejuniinfection in a small animal model

Abstract We set out to develop and characterize a small animal model of Campylobacter jejuni(CJ) infection that recapitulates human campylobacteriosis. Adult C57BL/6J mice are rendered susceptible to colonization and disease by pre-treatment with a zinc deficient diet and a broad-spectrum antibiotic cocktail. We have established this model with four strains with diverse capsular serotypes and flagellar groups, two key virulence factors for CJ pathogenesis. We measured colonization, weight loss, diarrhea, fecal inflammatory markers, and cytokine production by mesenteric lymphocytes and splenocytes. Diarrhea containing visible mucous and/or blood and degree of weight loss vary in severity depending on the strain and dose. Interestingly, we identified an inverse relationship between inoculum dose and levels of fecal inflammatory markers, with lower inoculum doses inducing significantly higher inflammation. We also observed production of IFNγ and IL-17 at day 9 post infection and despite no decrease in CJ colonization, IFNγ and IL-17 levels decreased by day 21 with a subsequent increase in IL-10 production. We also observed higher levels of IFNγ and IL-17 in mice challenged with strain CG8486 relative to those challenged with strain 81–176 pointing to potential strain differences. These differences observed were more striking in mesenteric lymphocytes versus splenocytes, indicating that local cellular responses differed from systemic responses. We have developed a model of inflammatory diarrhea in adult mice that exhibits hallmarks of CJ infection and further identified significant shifts in cytokine expression associated with the duration of infection, bacterial strain utilized, and therapeutic treatment. Research reported in this presentation is supported by Navy work unit number: 6000.RAD1.DA3.A0308 and CARB-X. CARB-X’s funding for this project is sponsored by the Cooperative Agreement Number IDSEP160030 from ASPR/BARDA and by awards from Wellcome Trust, the UK Global Antimicrobial Resistance Innovation Fund (GAMRIF) funded by the UK Government Department of Health and Social Care (DHSC) and the Bill &amp; Melinda Gates Foundation. The content is solely the responsibility of the authors and does not necessarily represent the official views of CARB-X or any of its funders. Disclaimers: The views expressed in this work are those of the authors and do not necessarily reflect the official policy or position of the Department of the Navy, Department of Defense, nor the U.S. Government. F. Poly is an employee of the U.S. Government. This work was prepared as part of official duties. Title 17 U.S.C. §105 provides that ‘Copyright protection under this title is not available for any work of the United States Government.’ Title 17 U.S.C. §101 defines a U.S. Government work as a work prepared by a military service member or employee of the U.S. Government as part of that person’s official duties.The animal study protocol was reviewed and approved by the Naval Medical Research Center IACUC in compliance with all applicable Federal regulations governing the protection of animals in research.

Allogeneic Mesenchymal Stem Cells and Its Conditioned Medium as a Potential Adjuvant Therapy for COVID-19

Recent research has demonstrated that mesenchymal stem cells (MSCs) potentially benefit and enhance coronavirus disease (COVID-19) recovery. This benefit occurs via a mechanism that promotes viral clearance by phagocytes and macrophages. This action occurs through the innate (increase in IL-10 production and decrease in TNF-α and IL-12 production) and the adaptive immune system (decrease in IL-17 production, promote regulatory T cell proliferation and inhibit effectors T cell proliferation). MSCs are expected to act as an anti-inflammatory in the hyper-inflammatory state of COVID-19. MSCs enhance immune cell replacement that have been overwhelmed or have been lost due to cytokine storm. Although vaccines are the answer to this pandemic, MSCs can improve COVID-19 patients, especially in patients with chronic illnesses. The focus on keeping death-rates low is a great opportunity for MSCs-based therapy for severe or critically ill patients. MSCs and conditioned medium have the potential to serve as adjunctive therapy in preventing the body's overactive defense response or the so-called cytokine storm caused by COVID-19.Keywords: adjuvant therapy, COVID-19, mesenchymal stem cells, secretome

Healthcare workers exposed to COVID-19 patients present an inflammatory status and Th2/Th17/Th22 immune profile: findings from before vaccine application in Brazil

Healthcare workers present an increased risk of contagion for the SARS-CoV-2 virus due to their labor exposure. Here, we describe the clinical, laboratory, and immunological characteristics of healthcare workers, before vaccine application, exposed to SARS-CoV-2-infected patients. We collected sociodemographic, clinical, and laboratory information from 50 professionals who worked during the COVID-19 pandemic at the Clinical Hospital of the Northwest in Brazil. The results showed that most workers are women, over 50 years old, and worked as nursing technicians. Approximately 56% of workers were positive for a previous infection by RT-PCR and/or anti-SARS-CoV-2-immunoglobulin tests. Increased levels of hematocrit, neutrophils, NK lymphocytes, and fibrinogen, were found in positive healthcare workers, suggesting a light inflammatory status. The immunological findings showed an increase in IL-17 production and a Th2/Th17/Th22 profile followed by high serology for anti-SARS-CoV-2 IgM and IgG. Those data reveal the importance of studies with healthcare workers to investigate if the continuous exposition to the virus may result in chronic activation of the immune system and/or pulmonary inflammation in this target group.

Copaiba Oil Resin Exerts an Additive Effect to Babassu Oil on Behavioral Changes in Human Endometriotic Cell Cultures.

Current drugs for the treatment of endometriosis are not able to completely cure the condition, and significant side effects hinder the continuation of treatment. Therefore, it is necessary to search for new drug candidates. In the present paper, the use of plant extracts is highlighted. Babassu oil and Copaiba oil resin have several therapeutic properties. We investigated the in vitro effects of two nanoemulsions containing oil extracted from Babassu (Orbignya speciosa) nuts (called SNEDDS-18) and/or oil resin extracted from Copaiba trunk (Copaifera langsdorffii) (called SNEDDS-18/COPA) on cultured human eutopic endometrium stromal cells from endometrial biopsies of patients without (CESC) and with (EuESC) endometriosis as well as human stromal cells from biopsies of endometriotic lesions (EctESC). CESC, EuESC, and EctESC were taken and treated with SNEDDS-18 and SNEDDS-18/COPA to evaluate their effects on cytotoxicity, cell morphology, proliferation, and signaling pathways. After 48 h of incubation with SNEDDS-18 and SNEDDS-18/COPA, cell viability and proliferation were inhibited, especially in EctESC. The lowest concentration of both nanoemulsions reduced cell viability and proliferation and broke down the cytoskeleton in EctESCs. After 24 h of treatment a decrease in IL-1, TNF-α, and MCP-1 was observed, as well as an increase in IL-10 production. Both nanoemulsions can affect endometriotic stromal cell behaviors, thus revealing two potential candidates for new phytotherapeutic agents for the management of endometriosis.

Chagas cardiomyopathy is associated with a high susceptibility to T. cruzi infection in monocyte-derived macrophages and a predominance of CD4+CD45RO+ T-cells with immunoregulatory patterns

The pathogenesis of Chronic Chagas Cardiomyopathy (CCC) is still not fully understood, and the persistence of the parasite in tissues seems to be essential for the onset and progression of heart disease, tissue destruction, and chronic inflammation. It is clear that the polarity found between the asymptomatic (IND) and cardiac clinical forms refers mainly to the mechanisms involved in the regulation of the host's immune response. Thus, to elucidate aspects of the susceptibility of host phagocytes to T. cruzi infection, the present study explored novel aspects of innate immune response, integrating data on susceptibility to infection and intracellular replication, using monocyte-derived macrophages from CCC patients, together with memory CD4+ T-cells (CD45RO+). The isolation of PBMC was conducted by means of in vitro infection assay with T. cruzi trypomastigotes and flow cytometry analysis of the intracytoplasmic cytokine production by CD4+T-cells. Our findings indicated that monocytes derived from individuals with CCC are more susceptible to the infection and replication of intracellular amastigotes. Moreover, the stimulation of CD4+ T-cells from CCC patients, together with T. cruzi trypomastigotes, induces a predominance of a regulatory response over a type 1 response, demonstrated by an increase in IL-10 production and a reduction in the IFN-γ and IFN-γ/IL-10. Suppression of the function of monocyte-derived macrophages, from CCC patients, to control trypomastigote infection and intracellular replication sheds light on a potential susceptibility of these cells isolated from peripheral blood, which may reflect the ineffectiveness of parasite control by phagocytes in cardiac tissues, which can subsequently result in serious heart disease.

Preventive Effect of Vitamin C on Dextran Sulfate Sodium (DSS)-Induced Colitis via the Regulation of IL-22 and IL-6 Production in Gulo(-/-) Mice.

Reactive oxygen species (ROS), which are exceptionally high in IBD lesions, are known to cause abnormal immune responses to inflammatory reactions in inflammatory bowel diseases (IBD) through damage to the intestinal mucosal linings. Moreover, they are theorized to be an agent of IBD development. Vitamin C is widely known to be an effective antioxidant for its ability to regulate inflammatory responses through its ROS scavenging effect. Therefore, we examined vitamin C’s influence on the development and progression of IBD in Gulo(−/−) mice, which cannot synthesize vitamin C like humans due to a defect in the expression of L-gulono-γ–lactone oxidase, an essential enzyme for vitamin C production. First, we found extensive oxidative stress and an inflammation increase in the colon of vitamin C-insufficient Gulo(−/−) mice. We also found decreased IL-22 production and NKp46(+) cell recruitment and the impaired activation of the p38MAPK pathway. Additionally, comparing vitamin C-insufficient Gulo(−/−) mice to vitamin C-sufficient Gulo(−/−) mice and wild-type mice, the insufficient group faced a decrease in mucin-1 expression, accompanied by an increase in IL-6 production, followed by the activation of the STAT3 and Akt pathways. The results suggest that vitamin C insufficiency induces severe colitis, meaning vitamin C could also take on a preventative role by regulating the production of cytokines and the induction of inflammation.