Neutrophil extracellular traps formation: effect of Leishmania major promastigotes and salivary gland homogenates of Phlebotomus papatasi in human neutrophil culture.

BACKGROUND: Leishmaniasis as a neglected tropical disease (NTD) is caused by the inoculation of Leishmania parasites via the bite of phlebotomine sand flies. After an infected bite, a series of innate and adaptive immune responses occurs, among which neutrophils can be mentioned as the initiators. Among the multiple functions of these fighting cells, neutrophil extracellular traps (NETs) were studied in the presence of Leishmania major promastigotes and salivary gland homogenates (SGH) of Phlebotomus papatasi alone, and in combination to mimic natural conditions of transmission. MATERIAL & METHODS: The effect of L. major and SGH on NETs formation was studied in three different groups: neutrophils + SGH (NS), neutrophils + L. major (NL), neutrophils + L. major + SGH (NLS) along with negative and positive controls in 2, 4 and 6 h post-incubation. Different microscopic methods were used to visualize NETs comprising: fluorescence microscopy by Acridine Orange/ Ethidium Bromide staining, optical microscopy by Giemsa staining and scanning electron microscopy. In addition, the expression level of three different genes NE, MPO and MMP9 was evaluated by Real-Time PCR. RESULTS: All three microscopical methods revealed similar results, as in NS group, chromatin extrusion as a sign of NETosis, was not very evident in each three time points; but, in NL and especially NLS group, more NETosis was observed and the interaction between neutrophils and promastigotes in NL and also with saliva in NLS group, gradually increased over times. Real-time reveals that, the expression of MPO, NE and MMP9 genes increased during 2 and 4 h after exposure, and then decreased at 6 h in most groups. CONCLUSION: Hence, it was determined that the simultaneous presence of parasite and saliva in NLS group has a greater impact on the formation of NETs compared to NL and NS groups.

Hypoxia and programmed cell death-ligand 1 expression in the tumor microenvironment: a review of the effects of hypoxia-induced factor-1 on immunotherapy.

One useful cancer treatment approach is activating the patient's immune response against the tumor. In this regard, immunotherapy (IT) based on immune checkpoint blockers (ICBs) has made great progress in the last two decades. Although ITs are considered a novel approach to cancer treatment and have had good results in preclinical studies, their clinical success has shown that only a small proportion of treated patients (about 20%) benefited from them. Moreover, in highly progressed tumors, almost no acceptable response could be expected. In this regard finding the key molecules that are the main players of tumor immunosuppression might be helpful in overcoming the possible burdens. Hypoxia is one of the main components of the tumor microenvironment (TME), which can create an immunosuppressive microenvironment in various ways. For example, hypoxia is one of the main factors of programmed cell death ligand-1 (PD-L1) upregulation in tumor-infiltrating Myeloid-Derived Suppressor Cells (MDSCs). Therefore, hypoxia can be targeted to increase the efficiency of Anti-PD-L1 IT and has become one of the important issues in cancer treatment strategy. In this review, we described the effect of hypoxia in the TME, on tumor progression and immune responses and the challenges created by it for IT.

Toxoplasma gondii profilin induces NLRP3 activation and IL-1ß production/secretion in THP-1 cells.

Toxoplasma gondii is a highly prevalent protozoan that infects a broad spectrum of warm-blooded animals. Profilin is a critical protein that plays a role in the movement and invasion of T. gondii. In the current study, we assessed how profilin stimulates inflammasomes and how it induces transcription and secretion of IL-1ß. For this purpose, we assessed the level of TLR 2, 4, 5, and 9 expressions in a THP-1 cell line treated with profilin from T. gondii (TgP). In addition, we analyzed the expression levels of various inflammasomes, as well as IL-1ß, and IL-18 in THP-1 cells treated with the NLRP3 inhibitor MCC950. TgP significantly increased the expression of TLR5 but the expression of TLR2, 4, and 9 was not significantly increased. In addition, TgP did not significantly increase the level of inflammasomes after 5 h. Treatment with MCC950 significantly reduced NLRP3 and IL-1ß on both transcription and protein levels. Although the transcription level of NLRP3 was reduced 5 h after treatment with TgP, western blot analysis showed an increase in NLRP3. The western blot and ELISA analysis also showed that TgP increased both pro- and mature IL-1ß. In summary, our study showed that NLRP3 most probably plays a pivotal role in the expression and production levels of IL-1ß during the interaction between TgP and macrophages.

Altered expression of leukemia inhibitory factor (LIF), LIFR, gp130, and IL11 in the embryo implantation site of rat model with prenatal androgen-induced polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that represents infertility in many reproductive-age women. Reduced implantation of blastocyst was proposed as an etiology for infertility in this syndrome. In this regard, many candidate genes such as leukemia inhibitory factor (LIF), LIF receptor (LIFR), glycoprotein 130 (gp130), and interleukin 11 (IL11) were proposed to be disrupted. Investigation of these genes is not ethically approved in pregnant women with PCOS. In this study, we aimed to compare the expression of LIF, LIFR, gp130, and IL11 before and during different gestational days in uterine tissues of prenatally-androgenized rat models of PCOS with control rats. The rat model of polycystic ovary syndrome was created by the injection of testosterone during prenatal life. RNA extraction and cDNA synthesis from uterine tissues were performed in both prenatal induced PCOS and control rats. Expression of LIF, LIFR, gp130, and IL11 genes was compared before pregnancy (GD0) and during pregnancy on GD0.5, GD4.5, GD5.5, and GD8.5 between two study groups (n = 6 each group) using SYBR Green real-time PCR. The expression of the LIF mRNAs significantly decreased on GD4.5, 5.5, and 8.5 in the PCOS rats compared to the controls (P-values: 0.0483, 0.0152, and 0.0043). Additionally, decreased expression of LIFR and gp130 was observed on GD0.5 to 8.5 in PCOS rats compared to controls (P-values: 0.022, 0.0480, 0.0043, 0.0022 for LIFR and 0.0189, 0.0022, 0.0087, 0.0022 for gp130). Moreover, IL-11 mRNA levels decreased in the PCOS group compared to their controls both before (P-value:0.0362) and during the gestational period (P-values:0.0085, 0.0043, 0.0389, 0.0087). Reduced expression of LIF, LIFR, gp130, and IL11 in the rats with PCOS indicates a possible disruption in the implantation and decidualization stages in this syndrome.

Evaluation the reactivity of a peptide-based monoclonal antibody derived from OmpA with drug resistant pulsotypes of Acinetobacter baumannii as a potential therapeutic approach.

BACKGROUND: Acinetobacter baumannii is an opportunistic and antibiotic-resistant pathogen that predominantly causes nosocomial infections. There is urgent need for development nonantibiotic-based treatment strategies. We developed a novel monoclonal antibody (mAb) against a peptide of conserved outer membrane protein A (OmpA) and evaluated its reactivity with different pulsotypes of A. baumannii. METHODS: Peptide derived from A. baumannii OmpA was conjugated to keyhole limpet hemocyanin and injected into BALB/c mice. Splenocytes of immunized mice were fused with SP2/0 myeloma cells followed by selection of antibody-producing hybridoma cells. After screening of different hybridoma colonies by ELISA, one monoclone was selected as 3F10-C9 and the antibody was tested for reaction with five different Acinetobacter pulsotypes that were resistant to carbapenem antibiotics. The affinity constant was measured by ELISA. The ELISA, western blotting, indirect immunofluorescence (IFA), and in vitro opsonophagocytosis assays were used to evaluate the reactivity of generated mAb. RESULTS: The anti-OmpA antibody reacted with the immunizing peptide and had a high affinity (1.94 × 10-9 M) for its antigen in the ELISA. Specific binding of mAb to OmpA was confirmed in Western blot. IFA assays revealed that mAb recognized specific OmpA on the pulsotypes. Opsonophagocytosis assays showed that the mAb increased the bactericidal activity of macrophage cells. The antibody function was higher in the presence of serum complement. CONCLUSIONS: The peptide-based mAb demonstrated optimal performance in laboratory experiments which may be appropriate in investigation on OmpA in Acinetobacter pathogenesis and development of passive immunization as a novel therapeutic approach.

Release of Interleukin-1ß evaluation among mineral oil mist-exposed workers.

Exposure to aerosols has been found to be linked to respiratory impairment. Although the effects of both indoor and outdoor exposures to particulates have been extensively reported, exposures to mists are less studied. Herein, we reported a survey of mineral oil mist toxicity in an occupational exposure scenario. For the purpose of this study, 65 lathe workers of the metal processing industry, as mineral oil mist-exposed population, were studied. Thereafter, the participants' age, smoking habits and work experience were matched with those of the control workers (n = 65) who were not occupationally exposed to mist. Thereafter, air samples were evaluated from the breathing zone of the workers using NIOSH method 5026. Plasma Interleukin-1ß as a pro-inflammatory indicator was assessed in all the studied subjects. Mean ± standard deviation of mineral oil mist time-weighted average exposure in lathe workers was 7.10± 3.49 mg/m3. IL-1ß cytokine levels were significantly higher in the lathe groups compared to the control group. The mean level of Interleukin-1ß in the control subjects (2922 pg/L) was selected as the cut-off point of the inflammation effect. Based on this pro-inflammatory point, the results of monitoring showed that 60% of the exposed were affected. A Spearman correlation was also found between mineral oil mist exposure and inflammation in the affected subjects. Our findings highlighted the immunological potential of mineral oil mist in occupational exposure. Overall, the results of this study suggested that Interleukin-1ß evaluation in mineral oil mist exposure could be considered as both an acute and chronic inflammation marker.

Soluble total antigen derived from Toxoplasma gondii tachyzoites increased the expression levels of NLRP1, NLRP3, NLRC4, AIM2, and the release of mature form of IL1ß, but downregulated the expression of IL1ß and IL18 genes in THP-1cell line.

Toxoplasma gondii (T. gondii) is an intracellular parasitic protozoan infecting homoeothermic animals and about a third of the world's population. Inflammasomes are intracellular multi-protein complex, which are activated by many factors. Inflammasomes are activated during toxoplasmosis; however, there are a lot of obscure aspects. THP-1 monocyte cells were converted to M0 macrophages by PMA and treated by 100 µg/mL soluble total Ag (STAg) derived from T. gondii strain RH for two time points 3 h and 24 h. After total RNA extraction and cDNA synthesis, the expression pattern of NLRP1, NLRP3, NLRC4, AIM2, IL1ß, and IL18 was evaluated by relative real-time PCR. In addition, the cytokine release of IL1ß and TNFα was evaluated in the supernatant of each well. The results showed statistically significant time-dependent overexpression of inflammasomes. NLRP1 and NLRP3 showed the higher and lower expression, respectively, during 3 h and 24 h after exposure. Both IL1ß and IL18 downregulated 3 h after exposure. IL18 presented statistically significant upregulation after 24 h, but IL1ß showed statistically significant downregulation after 24 h. The release of IL1ß increased after 3 h, but it slightly decreased during 24 h after exposure. The concentration of TNFα showed an insignificant decrease compared to control, while it increased during 24 h after exposure. Taken together, this study suggested that T. gondii STAg induces NLRP1 more than NLRP3, NLRC4, and AIM2. Our findings also proposed that T. gondii STAg downregulates the gene expression of IL1ß, but increases the release of this cytokine. It seems that Toxoplasma STAg probably increase the release of IL1ß via activating NLRPs and AIM2 to cleave pro-caspase 1 to caspase 1 that leads to conversion of pro IL1ß to mature IL1ß.

High prevalence of benign mammary tumors in a rat model of polycystic ovary syndrome during postmenopausal period.

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders in reproductive-age women. Significant associations between PCOS and benign breast diseases (BBD) and a possibly potential association between PCOS and breast cancer have been reported. The etiology of these events of mammary glands in PCOS remains unclear. Animal models that show BBD and breast cancer may contribute to further understanding about these diseases. We aimed to examine the spontaneous occurrence of mammary tumors, their prevalence, and type in our rat model of PCOS. Prenatal androgen-induced PCOS rats and controls were examined in later life. Benign mammary tumors were observed in 75% and 33.33% of PCOS rats and controls during the postmenopausal period, respectively (p = .0158). Mammary tumors were non-invasive, margins of excision were normal and tumors were freely movable, in both groups. After microscopic evaluations of tumors, proliferative breast lesions and adenomas with a tubular growth pattern were observed in both groups. However, in PCOS rats, of benign tumors two had a mixed pattern of fibroadenoma/fibroma and cysts. High prevalence of benign mammary tumors was observed in our rat model of PCOS during the postmenopausal period, possibly due to hormonal imbalances during their reproductive lifespan; this model may contribute to current data available regarding the events of mammary glands in PCOS.

Effects of Chlorella vulgaris on tumor growth in mammary tumor-bearing Balb/c mice: discussing association of an immune-suppressed protumor microenvironment with serum IFNγ and IgG decrease and spleen IgG potentiation.

PURPOSE: Chlorella vulgaris (CV) has exhibited immune-enhancing and protective activities against cancer and infections. However, there is an increasing concern about the use of Chlorella species in human, regarding its various molecules with antigenic features found in infectious microorganisms. Our goal was to investigate the impact of higher concentrations of CV on tumor growth in spontaneous mouse mammary tumor (SMMT) models. METHODS: Balb/c mice were daily given CV powder at doses of 0, 200, or 300 mg/kg for 42 days (CONTROL, CV200, and CV300 groups, respectively; n = 6/group). On day 14, the SMMT was inoculated. Tumor volume (TV) and body weight (BW) were monitored on 5-day intervals following tumor challenge. On day 43, blood, spleen, lungs, and tumor tissues were collected. Histopathological examinations on lungs and tumor tissues were performed following hematoxylin-eosin staining. Intratumor expression of 27 genes was assessed by real-time PCR. Total IgG, IFNγ, and IL-4 levels in serum and spleen culture supernatant were measured by ELISA. RESULTS: The TV/BW index showed significant increase in the CV200 group compared to the CONTROL (p = 0.047). The CV200 tumors exhibited more malignant phenotype, higher angiogenesis rate, and lower peritumoral neutrophil and macrophage-to-lymphocyte infiltration ratio compared to the CONTROL. Serum concentrations of IFNγ, IL-4, and IgG were declined, and the spleen IFNγ and IgG production was higher in the CV200 compared to the CONTROL. The IL-1ß, IL-10, TGFß1, FOXP3, HO-1, Gr1, CD11b, PCNA, LCN2, iNOS2, VEGFR2, CD31, and CD105L expressions were markedly increased in the CV200 tumors compared to the CONTROL (p = 0.001, 0.002, 0.006, 0.021, 0.004, 0.030, 0.016, 0.031, 0.025, 0.008, 0.014, 0.022, and 0.037, respectively). The changes in cytokine, IgG and gene expression values considerably correlated with tumor size, as well as with each other. CONCLUSIONS: Our data provided evidence that C. vulgaris at a specific dose (200 mg/kg) promoted tumor growth in a mammary tumor model. This consequence might reflect an immune derangement in favor of developing a protumor microenvironment. However, this hypothesis needs to be further investigated in future.

Reduction toxicity of Amphotericin B through loading into a novel nanoformulation of anionic linear globular dendrimer for improve treatment of leishmania major.

Amphotericin B (A) as an antileishmanial drug has limited clinical application owing to severe side-effects and low-water solubility. This is the first study reported using Anionic Linear Globular Dendrimer (ALGD) as A carrier for the increase of A solubility rate, decrease its toxicity, and improve its therapeutic effects. ALGD was synthesized and A was loaded into nanoparticles for the first time with the drug-loading efficiency of 82%. Drug loading was confirmed using characterization methods. The drug solubility rate was increased by 478-folds. The results of the study showed that the A toxicity was significantly decreased by 95% in vitro and in vivo environments, which was confirmed by pathology findings and enzymatic evaluation. Furthermore, the nanodrug caused that mortality rate was reached to zero. Moreover, the nanodrug was as potent as the free drug and glucantime (GUL) in reducing the parasite burden and parasite number. These findings indicated the potency of ALGD to decrease the drug side-effects, increase the drug solubility rate, and improve the drug efficacy. Moreover, the nanoformulation was a non-toxic and cost-effective formulation. The conformity between in vitro and in vivo results suggested that the A-loaded ALGD could be considered as a promising candidate in reducing the side-effects of A in leishmaniasis treatment.

Spontaneous mouse mammary tumor cell lysates induce IgG production in spleen mononuclear cells of healthy and tumor-bearing mice.

BACKGROUND: We hypothesized that Tumor cell lysate (TCL) prepared from spontaneous mouse mammary tumor (SMMT) may elicit IgG production by spleen mononuclear cells (SMCs) in ex vivo. METHODS: The SMCs from healthy mice (HM, n = 6) and four-week SMMT-bearing mice (TBM, n = 6) was cultured in presence of TCL and mitogen for 42 hr at 37°C, separately. Serum and SMCs culture supernatant levels of IFNγ, IL-4, and total IgG were measured using special ELISA kits. RESULTS: Serum IgG level of TBM was significantly higher than that of HM group (P = 0.019), while serum IFNγ and IL-4 did not differ between two groups (P > 0.05). Mitogen significantly induced ex vivo production of both IFNγ (P = 0.013) and IL-4 (P = 0.015) by SMCs from HM group, and only IL-4 (P = 0.049) by SMCs from TBM group. In contrast, TCL increased ex vivo production of IgG by SMCs from both HM (P = 0.034) and TBM (P = 0.016) groups. The ex vivo IgG revealed a moderate positive correlation with tumor size (r = 0.578, P = 0.422). CONCLUSION: It seems that TCL prepared from SMMT are potent inducers of IgG production. This may propose TCL as a potential tool for monitoring of humoral immunity in animal models.

Syphacia obvelata: A New Hope to Induction of Intestinal Immunological Tolerance in C57BL/6 Mice.

The ability of nematodes to manipulate the immune system of their host towards a Th2 and T regulatory responses has been proposed to suppress the inflammatory response. Clinical trials have proposed a useful effect of helminth infections on improvement of inflammatory disorders. In this study, we investigated the immunomodulatory effect of Syphacia obvelata infection to induce intestinal tolerance in C57BL/6 mice. Mice were infected through the cagemates with self-infected BALB/c mice. Four weeks post-infection, expression levels of IFN-γ, TNF-α, IL-17, and IL-10 were assessed in the supernatant of mesenteric lymph node (MLN) culture. Foxp3+Treg were measured in MLN cells by flow cytometry. In the S. obvelata-infected group, the percentage of Tregs (5.2±0.4) was significantly higher than the control (3.6±0.5) (P<0.05). The levels of IL-10 (55.3±2.2 vs 35.2±3.2), IL-17 (52.9±3.8 vs 41±1.8), IFN-γ (44.8±4.8 vs 22.3±2.3) and TNF-α (71.1±5.8 vs 60.1±3.3) were significantly increased in infected mice compared to the control group (P<0.05). The above results showed the potential effects of S. obvelata to induce intestinal tolerance. Therefore, it seems that S. obvelata may increase the immunological suppressive function in the intestinal tract.

Identification of antigens from nosocomial Acinetobacter baumannii clinical isolates in sera from ICU staff and infected patients using the antigenome technique.

Nosocomial infections with a bacterial origin are considered one of the most dangerous threats to global health. Among the causes of these infections, Acinetobacter baumannii is playing a significant role, and the present study aimed to determine the immunogenic proteins of this bacteria. Clinical isolates of A. baumannii were obtained from positive sputum cultures of intensive care unit (ICU) patients confirmed by Polymerase chain reaction (PCR) of the OXA-51 gene, and sera was obtained from 20 colonized patients. In addition, 20 and 30 serum samples were collected from ICU nurses and healthy controls, respectively. All the samples were screened in the presence of antibodies against A. baumannii by enzyme-linked immunosorbent assay (ELISA). IgG purified from the serum samples by affinity chromatography was used to isolate the bacteria by the Magnetic-activated cell sorting (MACS) procedure. After the bacteria were cultured, the identified antigen proteins were studied by western blotting and Mass spectrometry (MS). The MS results were analyzed with MASCOT software and revealed a 35 KD protein, which corresponds to outer membrane protein A (OmpA) of A. baumannii, a 25 KD band, which is a carbapenem-associated resistance protein precursor, and a 60 KD protein band, identified as a stress-induced bacterial acidophilic repeat motif protein. According to the properties of immunogen antigens and bio informatics tools, the outer membrane proteins (OMPs) can be used as a vaccine candidate in animal models.

The effects of low-level laser irradiation on cellular viability and proliferation of human skin fibroblasts cultured in high glucose mediums.

Delayed wound healing is one of the most challenging complications of diabetes mellitus (DM) in clinical medicine. This study has aimed to evaluate the effects of low-level laser therapy (LLLT) on human skin fibroblasts (HSFs) cultured in a high glucose concentration. HSFs were cultured either in a concentration of physiologic glucose (5.5 mM/l) or high glucose media (11.1 and 15 mM/l) for either 1 or 2 weeks after which they were subsequently cultured in either the physiologic glucose or high concentration glucose media during laser irradiation. LLLT was carried out with a helium-neon (He-Ne) laser unit at energy densities of 0.5, 1, and 2 J/cm(2), and power density of 0.66 mW/cm(2) on 3 consecutive days. HSFs' viability and proliferation rate were evaluated with the dimethylthiazol-diphenyltetrazolium bromide (MTT) assay. The LLLT at densities of 0.5 and 1 J/cm(2) had stimulatory effects on the viability and proliferation rate of HSFs cultured in physiologic glucose (5.5 mM/l) medium compared to their control cultures (p = 0.002 and p = 0.046, respectively). All three doses of 0.5, 1, and 2 J/cm(2) had stimulatory effects on the proliferation rate of HSFs cultured in high glucose concentrations when compared to their control cultures (p = 0.042, p = 0.000, and p = 0.000, respectively). This study showed that HSFs originally cultured for 2 weeks in high glucose concentration followed by culture in physiologic glucose during laser irradiation showed enhanced cell viability and proliferation. Thus, LLLT had a stimulatory effect on these HSFs.

Protective role of stem cells in POI: Current status and mechanism of action, a review article.

Premature ovarian insufficiency (POI) has far-reaching consequences on women's life quality. Due to the lack of full recognition of the etiology and complexity of this disease, there is no appropriate treatment for infected patients. Recently, stem cell therapy has attracted the attention of regenerative medicine scholars and offered promising outcomes for POI patients. Several kinds of stem cells, such as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) have been used for the treatment of ovarian diseases. However, their potential protective mechanisms are still unknown. Undoubtedly, a better understanding of the therapeutic molecular and cellular mechanisms of stem cells will address uncover strategies to increase their clinical application for multiple disorders such as POI. This paper describes a detailed account of the potential properties of different types of stem cells and provides a comprehensive review of their protective mechanisms, particularly MSC, in POI disorder. In addition, ongoing challenges and several strategies to improve the efficacy of MSC in clinical use are addressed. Therefore, this review will provide proof-of-concept for further clinical application of stem cells in POI.

Advances in nanotechnology for improving the targeted delivery and activity of amphotericin B (2011-2023): a systematic review.

Amphotericin B (AmB) is a broad-spectrum therapeutic and effective drug, but it has serious side effects of toxicity and solubility. Therefore, reducing its toxicity should be considered in therapeutic applications. Nanotechnology has paved the way to improve drug delivery systems and reduce toxicity. The present study, for the first time, comprehensively reviews the studies from 2011 to 2023 on reducing the in vitro toxicity of AmB. The findings showed that loading AmB with micellar structures, nanostructured lipid carriers, liposomes, emulsions, poly lactide-co-glycolide acid, chitosan, dendrimers, and other polymeric nanoparticles increases the biocompatibility and efficacy of the drug and significantly reduces toxicity. In addition, modified carbon nanoparticles (including graphene, carbon nanotubes, and carbon dots) with positively charged amine groups, PEI, and other components showed favorable drug delivery properties. Uncoated and coated magnetic nanoparticles and silver NPs-AmB composites had less cytotoxicity and more antifungal activity than free AmB. Citrate-reduced GNPs and lipoic acid-functionalized GNPs were also effective nanocarriers to reduce AmB cytotoxicity and improve anti-leishmania efficacy. In addition, zinc oxide-NPs and PEGylated zinc oxide-NPs showed favorable antifungal activity and negligible toxicity. According to a review study, carbon-based nanoparticles, metal nanoparticles, and especially polymer nanoparticles caused some reduction in the toxicity and improved solubility of AmB in water. Overall, considering the discussed nanocarriers, further research on the application of nanotechnology as a cost-effective candidate to improve the efficiency and reduce the cytotoxicity of AmB is recommended.

Chemical exposure and alveolar macrophages responses: 'the role of pulmonary defense mechanism in inhalation injuries'.

Epidemiological and clinical studies have indicated an association between particulate matter (PM) exposure and acute and chronic pulmonary inflammation, which may be registered as increased mortality and morbidity. Despite the increasing evidence, the pathophysiology mechanism of these PMs is still not fully characterised. Pulmonary alveolar macrophages (PAMs), as a predominant cell in the lung, play a critically important role in these pathological mechanisms. Toxin exposure triggers events associated with macrophage activation, including oxidative stress, acute damage, tissue disruption, remodelling and fibrosis. Targeting macrophage may potentially be employed to treat these types of lung inflammation without affecting the natural immune response to bacterial infections. Biological toxins, their sources of exposure, physical and other properties, and their effects on the individuals are summarised in this article. Inhaled particulates from air pollution and toxic gases containing chemicals can interact with alveolar epithelial cells and immune cells in the airways. PAMs can sense ambient pollutants and be stimulated, triggering cellular signalling pathways. These cells are highly adaptable and can change their function and phenotype in response to inhaled agents. PAMs also have the ability to polarise and undergo plasticity in response to tissue damage, while maintaining resistance to exposure to inhaled agents.

Study the effect of recombinant leukemia inhibitory factor on maintenance of pregnancy and frequency of regulatory T cells in abortion-prone mice.

Recurrent spontaneous abortion (RSA) can have a significant impact on a woman's quality of life. Understanding the mechanisms behind abortion is crucial for developing potential treatments. Among various models of abortion, the CBA/J(♀) × DBA/2J(♂) model stands out as the most extensively studied. This model reveals the influence of an altered immune system on resorption during pregnancy. The leukemia inhibitory factor (LIF) holds considerable importance as a secretory glycoprotein essential for successful implantation. Regulatory T cells (Tregs) have been found to produce high levels of LIF in both mice and humans. LIF plays a vital role in the development of Tregs by upregulating the expression of the Foxp3 transcription factor while downregulating the expression of RORγt. To investigate the impact of recombinant LIF (rLIF) on pregnancy maintenance and Treg cell frequency in abortion-prone (AP) mice, a specific recombinant protein was used in this study. The AP group consisted of CBA/J(♀) × DBA/2J(♂) mice, while the control group comprised CBA/J(♀) × BALB/c(♂) mice. Intraperitoneal injections of rLIF were administered to the AP group on the third day of pregnancy, and its effects on Treg cell frequency and pregnancy maintenance were examined during this period. Following rLIF injections on the fourteenth day of pregnancy, the expression of Foxp3 significantly increased in AP mice (p = 0.02,0.008). Additionally, AP mice injected with rLIF demonstrated a significant reduction in resorption rate (p = 0.01) and a notable increase in birth rate (p = 0.01,0.0005). These findings provide new insights into the potential benefits of LIF in treating RSA patients.

Dysregulation of Immunity in Pulmonary Fibrosis is Associated with Increased Myeloid-specific Triggering Receptor-1 and Transforming Growth Factor-beta1 Expression.

Fibrosing pneumonia (FP) is classified into usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP), each having its own etiology and prognosis. Both types of FP are progressive and chronic conditions with distinct etiologies. Cytokines and inflammatory mediators play critical roles in the pathogenesis of FP. Among them, the role of transforming growth factor beta-1 (TGF-ß1) and modulators triggering fibrosis are not well understood. In this study, the expression of triggering receptor expressed on myeloid cells-1 (TREM-1) as a stimulator for the production of TGF-ß1 and also CD4+CD25+Foxp3+ regulatory cells were investigted in FP patients. Sixteen UIP, 14 NSIP and 4 pulmonary fibrosis following Mycobacterium tuberculosis (TB) infection patients, were compared with 12 healthy controls. The frequency of blood CD14+TGF-ß1+ and CD14+TREM1+-gated monocytes and CD4+CD25+Foxp3+ regulatory T cells (Treg), as well as the plasma levels of TGF-ß1 and IL­10 were measured. Fibrosis patients compared to healthy controls had a greater frequency of CD14+TGF-ß1+ [15.9 (0.2-88.2) vs. 0.6 (0.2-11.0)] and CD14+TREM1+ [21.1 (2.3-91.2) vs. 10.3 (3.1-28.6)]-gated monocytes, and CD4+CD25+Foxp3+ [1.2 (0.3-3.6) vs. 0.2 (0.1-0.4)]-gated lymphocytes. Plasma TGF-ß1 were also significantly increased in patients with fibrosis compared to healthy controls [9316.2 (±5554.4) vs. 3787.5 (±2255.6)]. These results confirm the importance of TGF-ß1 and TREM1 in pulmonary fibrosis. It seems that this reciprocal cycle in healthy people is modulated by the production of IL­10 by Treg cells, thus limiting fibrosis, as observed in patients following TB infection. Further investigations are recommended to evaluate possible immunomodulatory mechanisms defects in pulmonary fibrosis.

Serum Level of Antibodies Against Novel Acinetobacter Baumannii OmpA-selected Peptides in ICU Staff: Promise for the Future of Vaccine Development.

Extensively drug-resistant Acinetobacter baumannii is considered one of the most dangerous threats to global health, requiring novel therapeutic interventions. The outer membrane protein A (OmpA) is an immunogenic agent that triggers immune responses. The current study evaluated serum antibody levels against previously determined immunogenic OmpA peptides from A baumannii in ICU staff. Serum samples were collected from 62 ICU staff members (representing the exposed group), healthy controls (representing the nonexposed group), and patients with systemic lupus erythematosus (SLE) (as controls for nonspecific antibody reactions). After excluding the cross-reactive antibodies via Escherichia coli lysate pretreatment, all the samples were assessed in the vicinity of A baumannii lysate by enzyme-linked immunosorbent assay (ELISA). All the positive samples were assessed for interaction with previously designed and selected peptides using ELISA. The protective potential of positive serum antibodies was surveyed in vitro using an opsonophagocytic study. The most antibody positive samples against one of the dominant peptides were determined in the ICU personnel (75%).  SLE serum samples did not react with candidate peptides. The strongest positive reaction was observed in serum treatment with one of the OmpA peptides (No. 5) with significant differences compared to other designed peptides. Our findings showed that ICU samples have substantially higher antibody levels than the nonexposed group; Positive samples show strong results in the opsonophagocytosiis assay. This study demonstrates A baumannii colonization at human mucosal surfaces, especially in exposed healthy workers. Novel OmpA-derived peptides could be used to identify immunogenic vaccine candidates. Therefore, more studies are needed  before this peptide and antibody levels are used in diagnosis, prevention, or treatment.