Cell Phagocytic Activity Research Articles

Potential of Mesenchymal Stem Cell-Derived Exosomes as a Novel Treatment for Female Infertility Caused by Bacterial Infections.

Neisseria gonorrhoeae and Chlamydia trachomatis are the most common causes of bacterial sexually transmitted diseases (STDs) with complications in women, including pelvic inflammatory disease (PID), ectopic pregnancy, and infertility. The main concern with these infections is that 70% of infected women are asymptomatic and these infections ascend to the upper female reproductive tract (FRT). Primary infection in epithelial cells creates a cascade of events that leads to secretion of pro-inflammatory cytokines that stimulate innate immunity. Production of various cytokines is damaging to mucosal barriers, and tissue destruction leads to ciliated epithelial destruction that is associated with tubal scarring and ultimately provides the conditions for infertility. Mesenchymal stem cells (MSCs) are known as tissue specific stem cells with limited self-renewal capacity and the ability to repair damaged tissues in a variety of pathological conditions due to their multipotential differentiation capacity. Moreover, MSCs secrete exosomes that contain bioactive factors such as proteins, lipids, chemokines, enzymes, cytokines, and immunomodulatory factors which have therapeutic properties to enhance recovery activity and modulate immune responses. Experimental studies have shown that local and systemic treatment of MSC-derived exosomes (MSC-Exos) suppresses the destructive immune response due to the delivery of immunomodulatory proteins. Interestingly, some recent data have indicated that MSC-Exos display strong antimicrobial effects, by the secretion of antimicrobial peptides and proteins (AMPs), and increase bacterial clearance by enhancing the phagocytic activity of host immune cells. Considering MSC-Exos can secrete different bioactive factors that can modulate the immune system and prevent infection, exosome therapy is considered as a new therapeutic method in the treatment of inflammatory and microbial diseases. Here we intend to review the possible application of MSC-Exos in female reproductive system bacterial diseases.

Клінічна ефективність фітоентеросорбенту в комплексному лікуванні хворих із вперше діагностованим деструктивним туберкульозом легень

Актуальність. Пошук патогенетичних методів лікування, що спрямовані на нормалізацію імунного статусу хворого на туберкульоз без призначення специфічних імуномодуляторів, залишається актуальним. Це стало основою для планування нашого дослідження. Ентеросорбенти є безпечними препаратами, що мають імуномодулюючі властивості, і ці властивості забезпечуються не прямим, а опосередкованим їх впливом на стан системного імунітету завдяки детоксикаційній дії. Мета дослідження — вивчити вплив фітоентеросорбенту на показники системного імунітету та ефективність застосування його в комплексному лікуванні хворих на вперше діагностований деструктивний туберкульоз легень. Матеріали та методи. У рандомізованому контрольованому дослідженні брали участь 125 пацієнтів. Це були хворі на лікарсько-чутливий туберкульоз органів дихання з розпадом легеневої тканини та без розпаду і 25 здорових добровольців. Вивчали стан гуморальної, клітинної ланок імунітету, нейтрофільного та моноцитарного фагоцитозу. А також проводили дослідження впливу використання фітоентеросорбенту в комплексній терапії хворих на туберкульоз на концентрацію протитуберкульозного препарату ізоніазиду в крові хворих. Результати. Використання в комплексній терапії хворих на лікарсько-чутливий вперше діагностований деструктивний туберкульоз легень фітоентеросорбенту не вплинуло на показники клітинного імунітету, але сприяло нормалізації показників його В-ланки — вірогідному зниженню кількості CD22+-лімфоцитів, рівня IgG, IgA та циркулюючих імунних комплексів у крові хворих, нормалізації фагоцитарної активності фагоцитуючих клітин. Використання фітоентеросорбенту в комплексному лікуванні хворих на туберкульоз не призвело до зниження концентрації протитуберкульозного препарату ізониазіду в крові хворих, а, навпаки, підвищило її и не сприяло появі побічних реакцій від прийому ізоніазиду. Висновки. Комплексне лікування хворих на лікарсько-чутливий вперше діагностований деструктивний туберкульоз легень з використанням фітоентеросорбенту призвело до підвищення ефективності лікування за темпами загоєння деструкцій на 21,4 %.

Dietary Agaricus blazei Spent Substrate Improves Disease Resistance of Nile Tilapia (Oreochromis niloticus) against Streptococcus agalactiae In Vivo

This study evaluated the effects of the feeding of spent mushroom substrate from Agaricus blazei on Nile tilapia (Oreochromis niloticus). The safety of 0–1000 μg/mL A. blazei spent substrate water extract (ABSSE) was demonstrated in the primary hepatic and splenic macrophages and the THK cell line (a cell line with characteristics of melanomacrophages) using a cytotoxicity assay. Here, 10 μg/mL of crude ABSSE promoted the phagocytic activity of macrophages and THK cells. Stimulating ABSSE-primed THK cells with lipopolysaccharides or peptidoglycan resulted in higher expression levels of four cytokine genes (e.g., interleukinz (IL)-1β, IL-12b, IL-8 and tumor necrosis factor α (TNFα)) and one cytokine gene (TNFα), respectively. An in vitro bacterial growth inhibition assay demonstrated that ABSSE could inhibit the growth of Streptococcus agalactiae. In the first feeding trial, Nile tilapia were fed with experimental feed containing 0, 1, or 5% of A. blazei spent substrate (ABSS) for seven and fourteen days followed by bacterial challenge assay. The best result was obtained when Nile tilapia were continuously fed for seven days on a diet containing 1% ABSS, with the survival rate being higher than in groups with 0% and 5% ABSS after challenge with S. agalactiae. In the second trial, fish were fed diets supplemented with 0% or 1% ABSS for seven days, and then all the groups were given the control feed for several days prior to bacterial challenge in order to investigate the duration of the protective effect provided by ABSS. The results showed that the protective effects were sustained at day 7 after the feed was switched. Overall, spent mushroom substrate from A. blazei is a cost-effective feed additive for Nile tilapia that protects fish from S. agalactiae infection.

Zoonotic Visceral Leishmaniasis: New Insights on Innate Immune Response by Blood Macrophages and Liver Kupffer Cells to Leishmania infantum Parasites.

Simple SummaryLeishmania infantum is a parasite that causes zoonotic visceral leishmaniasis, a disease that affects humans, wild and domestic animals, mainly domestic dogs. This parasite develops inside the macrophages and, concealed inside these cells, the parasite can invade the inner organs such as the spleen and liver, causing life-threatening disease. Therefore, a better understanding of the immune mechanisms exhibited by the macrophages when facing this parasite is needed to improve control strategies. Macrophages are cells of the immune system, existing in the peripheral blood and associated with different tissues in the mammal body, having the task to protect against microbiological threats. Interestingly, Leishmania can manipulate the macrophages into a non-active ghost-like state, allowing the parasite to stay in the host. The liver, which is a vital organ and a target for the parasite, has a resident population of macrophages designated as Kupfer cells. Thus, this study aims to evaluate the innate immune response exhibited by these two distinct cell populations—blood-macrophages and Kupfer cells—against Leishmania parasites. Our findings showed that Leishmania takes advantage of the natural disposition of blood macrophages to perform phagocytosis and facilitate parasite internalization, which rapidly subverts the immune mechanisms of macrophages. On the other hand, Kupfer cells are not extensively immune activated in the first contact with the parasite but seem to be more efficient in parasite infection, thus contributing to the ability of the liver to naturally restrain Leishmania dissemination.L. infantum is the aetiological agent of zoonotic visceral leishmaniasis (ZVL), a disease that affects humans and dogs. Leishmania parasites are well adapted to aggressive conditions inside the phagolysosome and can control the immune activation of macrophages (MØs). Although MØs are highly active phagocytic cells with the capacity to destroy pathogens, they additionally comprise the host cells for Leishmania infection, replication, and stable establishment in the mammal host. The present study compares, for the first time, the innate immune response to L. infantum infection of two different macrophage lineages: the blood macrophages and the liver macrophages (Kupffer cells, KC). Our findings showed that L. infantum takes advantage of the natural predisposition of blood-MØs to phagocyte pathogens. However, parasites rapidly subvert the mechanisms of MØs immune activation. On the other hand, KCs, which are primed for immune tolerance, are not extensively activated and can overcome the dormancy induced by the parasite, exhibiting a selection of immune mechanisms, such as extracellular trap formation. Altogether, KCs reveal a different pattern of response in contrast with blood-MØs when confronting L. infantum parasites. In addition, KCs response appears to be more efficient in managing parasite infection, thus contributing to the ability of the liver to naturally restrain Leishmania dissemination.

Effect of Methylmercury Exposure on Bioaccumulation and Nonspecific Immune Respsonses in Hybrid Grouper Epinephelus fuscoguttatus × Epinephelus lanceolatus.

Simple SummaryThe head kidney was primary organ that accumulated methylmercury in hybrid grouper. Muscle tissue had lower methylmercury content than the head kidney and liver. Nonspecific immune responses and bioaccumulation of methylmercury were linked to hybrid grouper health.Mercury (Hg) is a dangerous heavy metal that can accumulate in fish and is harmful when consumed by humans. This study investigated the bioaccumulation of mercury in the form of methylmercury (MeHg) and evaluated nonspecific immune responses such as phagocytic activity and superoxide anion (O2−) production in hybrid grouper (Epinephelus fuscoguttatus × E. lanceolatus). The hybrid grouper leukocytes were incubated with methylmercury chloride (CH3HgCl) at concentrations of 10–10,000 µg/L to determine cell viability, phagocytic activity, and O2− production in vitro. Subsequently, the grouper were exposed daily to CH3HgCl mixed in the experimental diets at concentrations of 0, 1, 5, and 10 mg/kg for 28 days. The bioaccumulation of MeHg in the liver, head kidney, and muscle tissue was measured, and the phagocytic activity and O2− production were evaluated. In vitro results indicated that cell viability was significantly lower than that of the control group at concentrations > 500 µg/L. The phagocytic rate and O2− production at concentrations ˃ 500 and ˃ 200 µg/L, respectively, were significantly lower than those of the control group. The dietary exposure demonstrated that MeHg accumulated more substantially in the liver and head kidney compared with the muscle tissue in the treatment groups. Moreover, the cumulative concentration significantly increased with higher concentrations and more days of exposure. The phagocytic rate and O2− production in the treatment groups were significantly lower than those in the control group from days 2 and 1, respectively. In conclusion, hybrid grouper accumulated significant MeHg in the liver and head kidney compared with the muscle tissue, and higher concentrations and more exposure days resulted in decreased cell viability, phagocytic activity, and O2− production.

Mesenchymal Stem Cells: Potential Role against Bacterial Infection

The worldwide spread of bacterial resistance makes finding new therapeutics to overcome this ongoing problem an urgent need. Mesenchymal stem cells (MSCs) exert potential inhibiting activity against bacterial infections. The antimicrobial activity of MSCs relies on direct and indirect effects by secreting paracrine factors with potential inhibiting activity against bacterial growth or stimulating the phagocytic activity of the immune cells. These effects appeared when MSCs or its secreted factors are administrated therapeutically. Therefore, MSCs based cell therapy could be considered as a novel promising strategy to enhance the antibiotic activity in multidrug resistant (MDR) infections.

Preclinical Studies into Specific Toxicity of a Candidate Drug Based on Complement C3 neodeterminant Recombinant Humanized Antibody for Treating Traumatic Brain Injuries

This study aims to assess the specific toxicity (allergenicity, immunotoxicity and reproduction toxicity) of a dosage form of complement C3 neodeterminant recombinant humanized antibody. The reactions of general anaphylaxis, active cutaneous anaphylaxis and delayed-type reaction demonstrated no drug-related signs of experimental animal sensitization and immediate or delayed hypersensitivity in the treated animals. It was found that, in doses exceeding significantly the expected human therapeutic dose, the drug has no effect on humoral and cell-mediated immune responses. In addition, the drug does not suppress the phagocytic cell activity thereby indicating the absence of immunotoxic effect. Moreover, the drug has no adverse effects on male and female reproduction, progeny embryonal development, as well as prenatal and postnatal progeny development. The obtained data can be used in future clinical studies of the drug safety.

Extracellular cardiolipin regulates select immune functions of astrocytes in a toll-like receptor (TLR) 4-dependent manner.

Cardiolipin (CL) is a mitochondrial phospholipid that may be released extracellularly from damaged or dying cells where it can act as a signaling molecule by interacting with the surrounding cells. Previous research demonstrates that extracellular CL regulates select immune functions of microglia in a toll-like receptor (TLR) 4-dependent manner. However, the effects of CL on astrocyte functions are unknown. Astrocytes are essential participants in diverse physiological brain functions; however, they become overactivated in chronic neuroinflammatory states, including Alzheimer's disease, contributing to damage and death of surrounding tissues and cells. Since astrocytes express TLR 4, we hypothesized that, by interacting with this receptor, extracellular CL modulates the secretion of cytokines and cytotoxins by astrocytes, as well as their phagocytic activity. We studied the effects of CL added to the culture media of primary murine astrocytes and human U118 MG astrocytic cells, which were used as astrocyte models. Fluorescent latex microspheres and synaptosomes were used to investigate the phagocytic activity of cells. The secretion of inflammatory cytokines was measured by the enzyme-linked immunosorbent assay or immunoblotting. U118 MG astrocyte supernatants were transferred to human SH-SY5Y neuronal cells to assess the secretion of cytotoxins. The expression of TLR 4 and glial fibrillary acidic protein (GFAP) by U118 MG astrocytic cells was quantified by immunostaining and immunoblotting, respectively. Extracellular CL alone upregulated the phagocytic activity of human U118 MG astrocytic cells and their secretion of monocyte chemoattractant protein (MCP)-1 and interferon (IFN)-β. Extracellular CL upregulated the phagocytic activity of primary murine astrocytes. TLR 4-specific antagonist TAK-242 inhibited CL-induced secretion of MCP-1 by human U118 MG cells. CL alone upregulated the cell-surface expression of TLR 4 by the same cell type. Extracellular CL inhibited the lipopolysaccharide (LPS)-induced increase in GFAP expression as well as the secretion of cytotoxins by U118 MG astrocytic cells. Extracellular CL may be used to modulate select functions of astrocytes, which become dysregulated in chronic neuroinflammatory states. Therefore, CL, or liposomes containing this phospholipid, could be used to ameliorate the chronic neuroinflammation and adverse astrocyte activation associated with Alzheimer's disease.

IL-1β, IL-17A, and IL-10: A Novel Axis Linked to Immunological Dysfunction May Pre-Empt Early Diagnosis of Sepsis after Cardiac Surgery

INTRODUCTIONSepsis caused by a dysregulated host response to infection, is a serious healthcare problem that results in very high mortality every year-round the globe. When left untreated, sepsis can potentially turn fulminant, making early diagnosis and intervention an essential component of the therapeutic strategy. Proinflammatory cytokines are necessary for initiating an effective inflammatory response against infection, whereas their excess production has been associated with tissue injury in multiple organ systems leading to increased mortality. In contrast, anti-inflammatory cytokines seem to be a prerequisite for controlling and down regulating the initial inflammatory response. But a sustained release of these biomolecules leads to a turn-down of immune activation within the host organism. In the clinical conundrums associated with sepsis, it was often observed that pathogen-responsive cells were exposed to a complex cytokine milieu. The excess production of proinflammatory cytokines is essential for the survival, replication and activation of phagocytic and cytotoxic immune cells. In conjunction with this proinflammatory activity, anti-inflammatory cytokines are also released which are involved in the occurrence of cellular anergy and impaired response to aetiologic agents, causing a compensatory anti-inflammatory response syndrome (CARS).Current practice in cardiac surgery is to review laboratory test results (CRP, PCT, blood culture) and clinical criteria (SOFA and STS) 48 h after surgery to diagnose sepsis. CRP and PCT lack sensitivity and specificity, whereas blood culture requires a long turnaround time and lacks sensitivity. Sepsis being an interplay between pro and anti-inflammatory response, the relative expression of immune biomarkers may provide a useful criterion for early diagnosis of sepsis. Thus, we aimed at investigating the variations in circulating levels of prominent cytokines and their potential use as a diagnostic marker of adult sepsis post cardiac surgery.MATERIALS AND METHODSIn this double-blinded cohort study, blood samples of adult patients undergoing cardiac surgery were collected before surgery (D -1), and on the post-operative day 1 (D +1) after the approval from the appropriate Institutional Ethics Committee. Patients who were deemed risky by EuroSCORE II risk stratification were included and immuno-compromised as well as patients with active infection before surgery were excluded. Plasma levels of IL-1β, IL-5, IL-6, IL-10, IL-17A and TNFα were determined using cytometric bead assay by flow cytometry and the results were analyzed using FCAP Array™ software. The data sets were analyzed (GraphPad Prism 5.02) and a p value of < 0.05 was considered statistically significant.RESULTSThe study was conducted with 34 patients (n=34) and un-blinded after retrieval of data. The cohort has 8 patients diagnosed with sepsis and 26 without sepsis based on STS criteria. Demographic details for both groups are summarized in Table 1. Cytokine and other biomarker expression levels before (D-1) and after (D+1) Surgery is summarized in Table 2. At D +1, IL-1β, TNF-α, IL-17A and IL-10 showed significantly higher concentration in sepsis group compared to non-sepsis group (Fig 1B). CRP, PCT, WBC and differential blood count were not showing any discriminatory potential between sepsis and non-sepsis patients at D +1. The ROC curves of the above four cytokine expression levels at D+1 was analyzed between sepsis and non-sepsis groups. A plasma IL-1β level of 0.25 pg/ml had a sensitivity of 87.5 % and a specificity of 53.8 % and a plasma IL-17A level of 1.78 pg/ml had a sensitivity of 75 % and specificity of 46.2 %. In addition, IL-10 level of 8.99 pg/ml in plasma showed a diagnostic sensitivity of 87.5 % and a specificity of 53.8% (Fig 1C). Based on the current observation we proposed a model of inflammatory cytokine dynamics involving IL-1β, IL-17A and IL-10 suggesting their role, which may lead to the development of sepsis (Fig 1D).CONCLUSIONWe identified a significant up regulation of circulating inflammatory cytokines at 24 h in patients who developed sepsis after cardiac surgery, earlier than any noticeable changes in conventional sepsis biomarkers. These results suggest the possibility of inflammatory cytokines as a diagnostic marker and may be a potential therapeutic target as well. The study needs to be validated further on a larger cohort of patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

PECULIARITIES OF THE WOUND PROCESS DEVELOPMENT IN PATIENTS WITH THERMAL INJURY WHEN USED SILVER PREPARATIONS IN BURN WOUNDS SURGICAL TREATMENT

Fundamental research in the field of burn wound development process highlights new pathogenetic mechanisms that underlie the improvement of medical practice, the main purpose of which is to create optimal conditions for early regeneration of the affected skin, as well as to eliminate the development of local and general complications. Irrational general and local treatment of wounds contribute to the slowing down of regenerative processes, thereby worsening the prognosis and consequences of thermal injury.&#x0D; It was found out that in patients of both study groups in the first period of the study the characteristics of the cellular composition of the wound impressions of the wound bottom of the area of thermal damage correspond to the degenerative type.&#x0D; In patients of the main group in the second term of the study in the area of thermal damage cells with high levels of functional and metabolic activity begin to appear, which increase antimicrobial resistance and reduce the risk of generalization of the infectious process which is the main source of burns.&#x0D; In patients of the main group, an increase in the activity of neutrophilic granulocytes in the induced test was found in the second term of the study, which, in our opinion, indicates the involvement of neutrophilic granulocytes with high functional and metabolic activity. Under conditions of significant activation of resident monocytes in response to injury in patients of the main group in the second and third term, the area of thermal damage migrates functionally effective monocytes. In patients of the main group the preservation of the activity of myeloperoxidase - the main enzyme of the oxygen-dependent phase of phagocytosis at the minimum subcompensated level, which leads to the preservation of the oxygen-dependent metabolic reaction of neutrophilic granulocytes in the subsequent study, Increases in the content of PAS-positive substances in neutrophilic granulocytes indicate the preservation of the functional reserve for activation and completion of the oxygen-independent phase of phagocytosis.&#x0D; The use of the developed treatment promotes the involvement of functionally active phagocytic cells in the burn wound, reduces the toxic load on monocytes and neutrophils, which helps to maintain their functional activity at the subcompensated level. These trends in patients of the main group reduce the risk of both local and general infectious complications of burn disease.&#x0D; It was found that the level of spontaneous functional activity in the HCT test is associated with the activity of resident monocytes. They form the primary barrier that protects the body from infection or harmful macromolecular complexes. Monocytes - "inflammatory", which constantly come from the free pool and their functional activity against microbial antigens is much higher than resident monocytes. An indicator of the activity of monocytes - "inflammatory" is an indicator of functional activity in the induced HCT test. The results of the study indicate that under conditions of significant activation of resident monocytes in response to injury in patients of the main group in the second and third terms of the area of thermal damage migrate functionally effective monocytes.

Human induced pluripotent stem cell-derived macrophages ameliorate liver fibrosis.

With an increasing number of patients with degenerative hepatic diseases, such as liver fibrosis, and a limited supply of donor organs, there is an unmet need for therapies that can repair or regenerate damaged liver tissue. Treatment with macrophages that are capable of phagocytosis and anti-inflammatory activities such as secretion of matrix metalloproteinases (MMPs) provide an attractive cellular therapy approach. Human induced pluripotent stem cells (iPSCs) are capable of efficiently generating a large-scale, homogenous population of human macrophages using fully defined feeder- and serum-free differentiation protocol. Human iPSC-macrophages exhibit classical surface cell markers and phagocytic activity similar to peripheral blood-derived macrophages. Moreover, gene and cytokine expression analysis reveal that these macrophages can be efficiently polarized to pro-inflammatory M1 or anti-inflammatory M2 phenotypes in presence of LPS + IFN-γ and IL-4 + IL-13, respectively. M1 macrophages express high level of CD80, TNF-α, and IL-6 while M2 macrophages show elevated expression of CD206, CCL17, and CCL22. Here, we demonstrate that treatment of liver fibrosis with both human iPSC-derived macrophage populations and especially M2 subtype significantly reduces fibrogenic gene expression and disease associated histological markers including Sirius Red, αSMA and desmin in immunodeficient Rag2-/- γc-/- mice model, making this approach a promising cell-based avenue to ameliorate fibrosis.

Effect of Electroactive Water Solutions on Homeostasis and Healing Processes of Intestinal Anastomosis Combined with Simulated Anemia in Wistar Rats.

Gastroduodenal bleeding is one of the most challenging issues in surgery nowadays. The crude mortality rate due to severe blood loss in gastrointestinal bleeding is very high. Therefore, the use of medications to prevent severe blood loss and protect cells from the harmful effects of hypoxia should be the focus of attention in these conditions. This experimental study was carried out to establish changes in blood parameters and humoral immunity in rats after intestinal anastomoses combined with acute blood loss after the application of catholyte and anolyte. The study included 45 male Wistar rats weighing 290-320 g that were divided equally (15 animals per group) into three groups of intact animals (group 1), animals exposed to the small bowel resection (1.5 cm) with the end-to-end anastomosis and simulated acute blood loss (group 2), and animals exposed to the small bowel resection with end-to-end anastomosis and simulated acute blood loss that were daily given catholyte in the postoperative period group (group 3). After the surgery, the rats were given a catholyte solution per os, and the operative wound was treated with an anolyte. The blood samples and the wall of the small intestine in the anastomotic zone were used as a biological substrate to study the effect of catholyte on changes in the body during the healing process. The experiment was conducted for 15 days, and the data were recorded in two intervals on the 5th and 15th days after starting the experiment. The analyzed materials evidenced that the use of catholyte and liquid with negative oxidoreduction potential (ORP) (minus 500-520 mV) resulted in positive changes in the blood cell count, humoral immunity, and phagocytic activity impaired after the small bowel resection and blood loss. The use of an anolyte disinfectant (liquid with positive ORP+710-770 mV) prevented bacterial contamination of the surgical wound. The obtained findings proved that the catholyte had a positive effect on humoral immunity and healing processes in the anastomotic zone. Furthermore, the anolyte prevented the development of purulent complications and inflammation in the area of the surgical wound, and therefore, promoted the healing processes.

CX3CL1(+) Microparticles-Induced MFG-E8 Enhances Apoptotic Cell Clearance by Alveolar Macrophages.

During the resolution phase of acute lung injury, apoptotic cells release CX3CL1 as a “find-me” signal to attract alveolar macrophage transmigration toward apoptotic cells for phagocytosis. However, it is still not clear whether CX3CL1 has pro-phagocytic activity on alveolar macrophage. In this study, we investigated the role of apoptotic NB4 cells-derived CX3CL1(+) microparticles (apo-MP) on the phagocytic activity of NR8383 cells. We demonstrate that exogenous CX3CL1 and apo-MP enhanced the phagocytic activity of NR8383 cells in a CX3 CR1-dependent manner. The apo-MP-enhanced phagocytic activity on NR8383 was attenuated when apo-MP and NR8383 cells were pre-treated with anti-CX3CL1 antibodies and anti-CX3CR1 antibody, respectively, before incubating both for phagocytic assay. Further studies demonstrate that exogenous CX3CL1 and apo-MP also enhanced NR8383 cells in their surface expression and release of MFG-E8 in a CX3CR1 dependent manner. The enhanced phagocytic activity of CX3CL1-treated NR8383 cells was attenuated when NR8383 cells were pre-treated with an anti-MFG-E8 antibody before CX3CL1 treatment. We conclude that apoptotic cell-derived CX3CL1(+) microparticles enhance the phagocytic activity of NR8383 cells by up-regulating their MFG-E8 as a bridge molecule, and these contribute to the formation of phagocytic synapses between apoptotic cells and alveolar macrophages for the subsequent phagocytic clearance of apoptotic cells.

Protective CD4+ Th1 cell-mediated immunity is reliant upon execution of effector function prior to the establishment of the pathogen niche.

Intracellular infection with the parasite Leishmania major features a state of concomitant immunity in which CD4+ T helper 1 (Th1) cell-mediated immunity against reinfection coincides with a chronic but sub-clinical primary infection. In this setting, the rapidity of the Th1 response at a secondary site of challenge in the skin represents the best correlate of parasite elimination and has been associated with a reversal in Leishmania-mediated modulation of monocytic host cells. Remarkably, the degree to which Th1 cells are absolutely reliant upon the time at which they interact with infected monocytes to mediate their protective effect has not been defined. In the present work, we report that CXCR3-dependent recruitment of Ly6C+ Th1 effector (Th1EFF) cells is indispensable for concomitant immunity and acute (<4 days post-infection) Th1EFF cell-phagocyte interactions are critical to prevent the establishment of a permissive pathogen niche, as evidenced by altered recruitment, gene expression and functional capacity of innate and adaptive immune cells at the site of secondary challenge. Surprisingly, provision of Th1EFF cells after establishment of the pathogen niche, even when Th1 cells were provided in large quantities, abrogated protection, Th1EFF cell accumulation and IFN-γ production, and iNOS production by inflammatory monocytes. These findings indicate that protective Th1 immunity is critically dependent on activation of permissive phagocytic host cells by preactivated Th1EFF cells at the time of infection.

The Paradox of a Phagosomal Lifestyle: How Innate Host Cell-Leishmania amazonensis Interactions Lead to a Progressive Chronic Disease.

Intracellular phagosomal pathogens represent a formidable challenge for innate immune cells, as, paradoxically, these phagocytic cells can act as both host cells that support pathogen replication and, when properly activated, are the critical cells that mediate pathogen elimination. Infection by parasites of the Leishmania genus provides an excellent model organism to investigate this complex host-pathogen interaction. In this review we focus on the dynamics of Leishmania amazonensis infection and the host innate immune response, including the impact of the adaptive immune response on phagocytic host cell recruitment and activation. L. amazonensis infection represents an important public health problem in South America where, distinct from other Leishmania parasites, it has been associated with all three clinical forms of leishmaniasis in humans: cutaneous, muco-cutaneous and visceral. Experimental observations demonstrate that most experimental mouse strains are susceptible to L. amazonensis infection, including the C57BL/6 mouse, which is resistant to other species such as Leishmania major, Leishmania braziliensis and Leishmania infantum. In general, the CD4+ T helper (Th)1/Th2 paradigm does not sufficiently explain the progressive chronic disease established by L. amazonensis, as strong cell-mediated Th1 immunity, or a lack of Th2 immunity, does not provide protection as would be predicted. Recent findings in which the balance between Th1/Th2 immunity was found to influence permissive host cell availability via recruitment of inflammatory monocytes has also added to the complexity of the Th1/Th2 paradigm. In this review we discuss the roles played by innate cells starting from parasite recognition through to priming of the adaptive immune response. We highlight the relative importance of neutrophils, monocytes, dendritic cells and resident macrophages for the establishment and progressive nature of disease following L. amazonensis infection.

Immunomodulatory effects of different molecular weight sporisorium reilianum polypeptides on LPS-induced RAW264.7 macrophages

Sporisorium reilianum is an edible fungus that contains polysaccharides, proteins, vitamins, and minerals. Although polysaccharides from S. reilianum have been shown to exert anti-inflammatory and anti-tumor effects, studies of other molecules are still scarce. This study was conducted to examine the immunomodulatory effects of different molecular weights of S. reilianum polypeptides (SRP) on lipopolysaccharide (LPS)-induced RAW264.7 macrophages. A neutral protease was used to prepare SRP, which was divided into different components based on their molecular weights (SRP1, SRP2, SRP3, and SRP4). Evaluation of the immunomodulatory effects of SRP on LPS-induced RAW264.7 macrophages showed that SRP enhanced cell viability and phagocytic activity, and effectively decreased the nitric oxide (NO) content. Furthermore, the SRP with the smallest molecular weight, SRP4 (500–1000 Da) exhibited the strongest effects compared to the other groups. Secretion of the pro-inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-6 was markedly decreased by SRP4 in a dose-dependent manner. Moreover, the mRNA expression levels of IL-1β, nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and toll-like receptor (TLR)-9 in RAW264.7 macrophages were also significantly downregulated by SRP4. Taken together, SRP, particularly SRP4, showed good immunomodulatory effects, indicating its potential as an immune-enhancing agent.

Porous particles and novel carrier particles with enhanced penetration for efficient pulmonary delivery of antitubercular drugs

This study aimed to design dry powder inhaler formulations using a hydrophilic polymeric polysaccharide, phytoglycogen (PyG), as a multi-functional additive that increases the phagocytic activity of macrophage-like cells and enhances pulmonary delivery of drugs. The safety and usefulness of PyG were determined using in vitro cell-based studies. Dry powder inhaler formulations of an antitubercular drug, rifampicin, were fabricated by spray drying with PyG. The cytotoxicity, effects on phagocytosis, particle size, and morphology were evaluated. The aerosolization properties of the powder formulations were evaluated using an Andersen cascade impactor (ACI). Scanning electron microscope images of the particles on each ACI stage were captured to observe the deposition behavior.PyG showed no toxicity in A549, Calu-3, or RAW264.7 cell lines. At concentrations of 0.5 and 1 g/L, PyG facilitated the cellular uptake of latex beads and the expression of pro-inflammatory cytokine genes in RAW264.7 cells. Formulations with outstanding inhalation potential were produced. The fine particle fraction (aerodynamic size 2–7 µm) of the porous particle batch reached nearly 60%, whereas in the formulation containing wrinkled carrier particles, the extra-fine particle fraction (aerodynamic particle size < 2 μm) was 25.0% ± 1.7%. The deposition of porous and wrinkled particles on individual ACI stages was distinct. The inclusion of PyG dramatically improved the inhalation performance of porous and wrinkled powder formulations. These easily inhaled immunostimulatory carrier particles may advance the state of research by enhancing the therapeutic effect and alveolar delivery of antitubercular drugs.

Readiness of periodontal cells to complete phagocytosis in patients with chronic coronary syndromes

Background and Aims: The connection between chronic coronary syndromes and periodontitis was shown in many studies, but the exact mechanism of this interaction are unknown. The aim of the study was to determine the state of phagocytic activity of the periodontium cells in patients with chronic coronary syndromes.

Developmental thyroid disruption causes long-term impacts on immune cell function and transcriptional responses to pathogen in a small fish model

Current evidence suggests thyroid hormones (THs) impact development of the immune system, but few studies have explored the connection between the thyroid and immune systems, especially in fish. This is important as some environmental contaminants disrupt TH homeostasis and may thus have negative impacts on the immune system. To determine the long-term consequences of early life stage (ELS) hypothyroidism on immune function, fathead minnows were exposed to the model thyroid hormone suppressant propylthiouracil (PTU) from < 1 to 30 days post hatch. Fish were transferred to clean water and raised to adulthood (5–7 months post hatch) at which time, several aspects of immune function were evaluated. Ex vivo assessment of immune cell function revealed significant decreases (1.2-fold) in the phagocytic cell activity of PTU-treated fish relative to the controls. Fish were also injected with Yersinia ruckeri to evaluate their in vivo immune responses across a suite of endpoints (i.e., transcriptomic analysis, leukocyte counts, spleen index, hematocrit, bacterial load and pathogen resistance). The transcriptomic response to infection was significantly different between control and PTU-treated fish, though no differences in bacterial load or pathogen resistance were noted. Overall, these results suggest that early life stage TH suppression causes long-term impacts on immune function at the molecular and cellular levels suggesting a key role for TH signaling in normal immune system development. This study lays the foundation for further exploration into thyroid-immune crosstalk in fish. This is noteworthy as disruption of the thyroid system during development, which can occur in response to chemicals present in the environment, may have lasting effects on immune function in adulthood.

Сучасний підхід до терапії атопічного дерматиту консервованими клітинами фетальної печінки (експериментальне дослідження)

One of the urgent problems of modern dermatology is atopic dermatitis (AD), which has multifactorial pathogenesis, the significant prevalence of the disease, the increased frequency of the complicated course, the lack of radical methods of therapy. The expediency to use cryopreserved fetal liver cells (cFLCs) for the treatment of AD is proved by a wide range of produced by them biologically active substances with immunomodulatory and anti-inflammatory activity. Disclosure of the mechanisms of the therapeutic action of biotherapeutic drugs in AD provides for the determination of the state of the cellular and humoral links of the immune system (IS). In this regard, the aim of the work was to assess the effectiveness of cFLCs injection by characteristic clinical and immunological parameters in rats with AD. The results of the study in rats with AD revealed disorders in the IS, manifested in a decrease in the total number of T-lymphocytes and their subpopulations in the spleen, in an increase in the level of circulating immune complexes and a number of immunoglobulins in the blood serum, and in a decrease in the phagocytic activity of the peritoneal cavity cells. Therapy with cFLCs, in contrast to the standard treatment with prednisolone, significantly improves the therapeutic effect, which is demonstrated by the restoration of the parameters of the cellular and humoral links of the immune system in animals with AD. The amplifying effect of the combined use of cFLCs and prednisolone on a number of parameters of the immune system in AD was shown.