Clostridium perfringens Epsilon Toxin Mutant I51C as a Recombinant Vaccine Candidate Against Enterotoxemia.

BACKGROUND: Clostridium perfringens type B and D strains produce epsilon toxin (ETX), which can lead to enterotoxemia, an extremely lethal disease that has significant consequences for the farming of domestic ruminants, specifically sheep and goats. The bacterin-toxoids/toxoids enterotoxemia vaccines need time-consuming detoxification steps. Genetically derived toxoids (GTs) can be the alternative vaccines against ETX-associated enterotoxemia. This study was aimed to design, synthesize, and evaluate of five epsilon toxin mutants of C. perfringens by site-directed mutagenesis (SDM). METHODS: In this study, five ETX mutants (H106P, I51C, V56C, A114C, and F118C), as ETX-GTs, were designed and synthesized by SDM, which were then cloned in pET-26b (+) and expressed in Escherichia coli /BL21 (DE3). The expression of recombinant ETX-GTs was evaluated by SDS-PAGE, blotting, and ELISA and their toxicity was evaluated by the residual toxicity test based on BP Pharmacopoeia, 2021. RESULTS: The findings showed that the ETX-GTs could be considered alternative vaccine candidates against ETX-associated enterotoxemia. CONCLUSIONS: These data suggest that I51C mutant could form the basis of an improved recombinant vaccine against enterotoxemia.

Toll-like receptors and Streptococcus mutans: An updated review article.

It has been reported that toll-like receptors (TLRs) are the main innate immune receptors that recognize gram-positive pathogen-associated molecular patterns (PAMPs). The molecules can induce expression of the innate immune-related molecules that are essential against the bacteria. Streptococcus mutans (S. mutans) is a potential caries-associated pathogen, and innate immunity plays a key role in inhibiting its development and the progression of inflammatory responses. Recently, the roles played by TLRs against S. mutans and the induction of inflammatory responses were evaluated by several investigations. This review article discusses updated information regarding the roles played by TLRs and their potential therapeutic effects against S. mutans.

The Potential Roles Played by miR-2113 and miR-568 in the Severe SARS-CoV-2 Infection Pathogenesis.

BACKGROUND: Severe SARS-CoV-2 infection is significantly associated with over-expression of some immune-related molecules and inflammation. MicroRNAs are known to regulate the expression of various molecules, including those related to immune function. However, the specific roles played by miR-2113 and miR-568 in the pathogenesis of severe COVID-19 remain unclear. METHODS: In this project, levels of miR-2113 and miR-568 were explored in 70 severe COVID-19 patients in parallel with 70 healthy subjects using real-time PCR technique. RESULTS: The results showed that miR-2113 and miR-568 levels significantly increased in the severe COVID-19 patients in comparison to healthy controls. Age and gender had no correlations with expressions of miR-2113 and miR-568 in both severe COVID-19 patients and healthy controls. CONCLUSIONS: According to the results, miR-2113 and miR-568 might be involved in inducing the expression of molecules that are associated with acute inflammation during severe infections like COVID-19, regardless of age and gender.

Systematic levels of IL-29 and microRNA185-5p were not associated with severe COVID-19 in the Iranian population.

BACKGROUND: Increased systematic pro-inflammatory cytokines is the main cause of the inflammatory conditions of the hospitalized severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected patients. In this project, serum levels of IL-29 and whole blood levels of microRNA-185-5p (miR-185-5p) were evaluated in the hospitalized SARS-CoV-2 infected patients. METHODS: This project was performed on the 60 hospitalized SARS-CoV-2 infected patients and 60 healthy controls to evaluate IL-29 and miR185-5p expression levels. IL-29 expression was explored using enzyme linked immunoassay (ELISA), while miR185-5p was evaluated using Real-Time PCR techniques. RESULTS: The results demonstrated that neither IL-29 serum levels nor relative expressions of miR-185-5p were significantly different between patients and healthy controls. CONCLUSION: Due to the results that are presented here, systematic levels of IL-29 and miR-185-5p cannot be considered as the main risk factors for induction of inflammation in the hospitalized SARS-CoV-2 infected patients.

MicroRNA-155 is a main part of proinflammatory puzzle during severe coronavirus disease 2019 (COVID-19).

Genetic and epigenetic parameters play critical roles in determining the outcomes of the severe acute respiratory syndrome coronavirus type 19 (SARS-CoV-2) infection. MicroRNAs (miRNAs) are an important part of the epigenetic factors that regulate several functions of the immune cells and also viruses. Accordingly, the molecules can regulate expression of the immune cell proteins and virus in the host cells. Among the miRNAs, miRNA-155 (miR-155) is well-studied in patients suffering from severe coronavirus disease 2019 (COVID-19). It has been reported that the SARS-CoV-2 infected patients may be directed to induce a cytokine storm or severe proinflammatory responses. This review article discusses the pathological roles of miR-155 during COVID-19 infection.

MicroRNA-155 and 194 alter expression of Th17 and T regulatory-related transcription factors in the patients with severe coronavirus disease 2019 (COVID-19).

INTRODUCTION: It has been demonstrated that the patients with severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) suffer from severe inflammation. Due to the ethnics, the immune responses may be different. Additionally, microRNAs may alter immune responses in the patients. The current study was aimed to evaluate the expression of T helper subsets-related transcription factors, some T helper 17 (Th17) products, and two microRNAs, including miR-155 and miR-194, in the Iranian hospitalized patients. METHODS: In this study, T-box expressed in T cells (T-bet), GATA binding protein 3, The retinoid orphan receptor gamma t (RORγt), forkhead box P3 (FOXP3), interleukin (IL)-17A, IL-8, and CC ligand 20 (CCL20) mRNA levels and, miR-155 and miR-194 levels were evaluated in 70 patients suffered from severe coronavirus disease 2019 (COVID-19) and 70 healthy subjects using Real-Time qPCR technique. RESULTS: The findings showed that RORγt, and FOXP3 mRNA levels were significantly increased, while IL-17A, IL-8, and CCL20 mRNA levels were significantly decreased in the hospitalized SARS-CoV-2 infected patients. Although the levels of miR-155 and miR-194 were not different between groups, miR-194 has negative and positive correlations with RORγt and IL-17A in the Iranian healthy controls. CONCLUSION: This study reports although RORγt was up-regulated, IL-17A, IL-8, and CCL20 mRNA levels were significantly decreased in the hospitalized SARS-CoV-2 infected patients. It may be concluded that up-regulation of FOXP3, via development of T regulatory lymphocytes suppresses Th17 functions and neutralizes Th17 activities. MiR-194 may play crucial roles in regulation of RORγt and IL-17A expression in healthy people, the phenomenon that is disrupted in the severe SARS-CoV-2 infected patients.

Effect of Royal Jelly on Gene Expression of Toll-like Receptors 1-9 in Patients with Hepatitis B.

BACKGROUND: By damaging the liver, hepatitis B can result in acute and chronic diseases, such as cirrhosis or hepatocellular carcinoma. Viable treatments for such diseases using natural products and determinative biomarkers have been proposed but require evaluation to improve their effects. Therefore, this study aims to examine how effectively a specific natural product (namely, royal jelly) protects the body from the copy number of the virus, as well as TLR1 to TLR9 gene expressions. METHODS: The effectiveness of royal jelly was tested by giving it (orally) to 30 hepatitis B patients for one month. HBV copy number and mRNA levels of TLRs were explored using Real Time PCR technique, and liver enzymes were evaluated too. RESULTS: Orally treatment with royal jelly led to a significant decrease in HBV-DNA copy number, down-regulation of TLR2 and TLR8, and up-regulation of TLR3. However, mRNA levels of the TLRs were not altered in the female, while TLR1, TLR2, and TLR5 were significantly decreased in the male participants. CONCLUSIONS: It seems that royal jelly has anti-viral and anti-inflammatory roles in the in vivo conditions in a dependent manner in TLR3, TLR2, and TLR8. Therefore, it can be suggested as a safe complementary agent for patients with hepatitis B.

Retinoic acid-inducible gene 1 (RIG-1) and IFN-ß promoter stimulator-1 (IPS-1) significantly down-regulated in the severe coronavirus disease 2019 (COVID-19).

INTRODUCTION: Retinoic acid-inducible gene 1 (RIG-1) and melanoma differentiation-associated protein 5 (MDA5) are the well-known cytoplasmic sensors that recognize microbial DNA or RNA and active down-stream molecules, including IFN-ß promoter stimulator-1 (IPS-1) and receptor interacting protein 1 (RIP1). The roles played by the networked molecules on the infection with SARS-CoV-2 needs more investigations. MATERIAL AND METHOD: In this project MDA5, RIG-1, IPS-1 and RIP1 mRNA levels were evaluated in 45 hospitalized patients suffering from coronavirus disease of 2019 (COVID-19) and 45 healthy subjects using Real Time-qPCR technique. RESULT: The results showed significant decreased RIG-1 and IPS-1 in the SARS-CoV-2 infected patients when compared to healthy cases. MDA5 and RIP1 did not change when compared two groups. Male patients had similar expression of MDA5, RIG-1, IPS-1 and RIP1 when compared to female patients. CONCLUSION: Based on the results, it seems that RIG-1 and its signaling molecule, IPS-1, play key roles in the peripheral blood immune cells against SARS-CoV-2 and, their down-regulation may be induced by the virus to escape from immune responses.

Upregulation of Toll-Like Receptors 2, 5, 7, and 9 in the Cervical Epithelial Cells of Iranian Women Infected with High-Risk Human Papilloma Virus.

BACKGROUND: Toll-like receptors (TLRs) play dual roles against viruses, including defense against the viruses and induction of the viral-related cancers. High risk human papilloma viruses (HPVs) play key roles in induction of HPV-related cancers. The molecules that are upregulated by the high-risk viruses can be considered as the candidate to induce the cancers. This project was designed to evaluate expression of TLR1-9 in the women infected with HPV-high risk genotypes. METHODS: This project was performed on 40 women infected with high-risk HPV genotypes and 40 healthy controls. Infections with HPV-high risk genotypes and relative expressions of TLR1-9 were explored using real-time PCR technique. RESULTS: Relative expressions of TLR2, TLR5, TLR7, and TLR9 were significantly higher in the HPV-high risk genotype infected participants when compared to non-infected cases. CONCLUSIONS: Due to the results, it appears that TLR2, TLR5, TLR7, and TLR9 are more important than other TLRs in the pathogenesis of cancers in the Iranian women, who are infected with HPV-high risk genotypes.

TLR9 in the Human Papilloma Virus Infections: Friend or Foe?

Immune system plays dual roles during human papilloma virus (HPV) infections, from defense against the virus to induction or stimulation of the HPV-related cancers. It appears that various differences within the immune-related genes and the functions of the immunological parameters of the patients are the main factors responsible for the roles played by immune system during HPV infections. Toll-like receptors (TLRs) play key roles in the recognition of viruses and activation of immune responses. The molecules also can alter the target cell intracellular signaling and may participate in the transformation of the infected cells. TLR9 is the unique intracellular member of TLRs that recognize foreign DNA, including viral DNA. Thus, TLR9 may play significant roles in the defense against HPV and its related cancers. This review article discusses TLR9 antiviral and pathological roles during HPV infection.

TLR2, as a Pathogen Recognition Receptor, Plays Critical Roles in Hepatitis B Outcome.

The immune system of active and inactive chronic hepatitis B, as prolonged forms of hepatitis B, is unable to eradicate hepatitis B virus (HBV) from the infected hepatocytes completely. Toll-like receptors (TLRs) play key roles in the viral recognition and promotion of appropriate immune responses. The molecules also participate in the alteration of the target cell functions and transformation. TLR2 is the unique molecule that makes either homodimer or heterodimer with TLR1 and 6 and shows variable roles against viral infections. Therefore, it has been hypothesized that TLR2 may participate in both immune response against HBV and induction of the virus-related hepatic complications. The studies confirm the hypothesis and revealed that TLR2 is not only one of the main molecules altering the course of HBV infection, but also plays key roles in induction of hepatocellular carcinoma (HCC) and liver cirrhosis. However, recent studies demonstrated that the molecule can fight against HCC and liver cirrhosis. Collectively, it appears that nutrition habits, TLR2 gene polymorphisms, gut microbiome, HBV antigens, and activation of other receptors may play key roles in the determination of TLR2 functions.

CC and CXC chemokines play key roles in the development of polyomaviruses related pathological conditions.

It has been reported that polyomaviruses are the microbes which can be a cause of several human pathological conditions including cancers, nephropathy, progressive multifocal leukoencephalopathy and gynaecological disease. Although investigators proposed some mechanisms used by the viruses to induce the disorders, the roles played by chemokines in the pathogenesis of polyomaviruses infections are yet to be clarified. This review article investigated recent studies regarding the roles played by chemokines in the pathogenesis of the polyomaviruses infections. The research in the literature revealed that CXC chemokines, including CXCL1, CXCL5, CXCL8, CXCL9, CXCL10, CXCL11, CXCL12 and CXCL16, significantly participate in the pathogenesis of polyomaviruses. CC chemokines, such as CCL2, CCL5 and CCL20 also participate in the induction of the pathological conditions. Therefore, it appears that CXC chemokines may be considered as the strategic factors involved in the pathogenesis of polyomaviruses.

Up-regulation of AIM2 and TLR4 and down-regulation of NLRC4 are associated with septicemia.

PURPOSE: Innate immunity receptors play key roles in recognition of bacterial associated molecular patterns. Inflammasomes and toll like receptors (TLRs) are the important innate immunity receptors. In this project transcription levels of TLR4, a TLR member, absent in melanoma 2 (AIM2) and NLR family CARD domain-containing protein 4 (NLRC4), as inflammasomes, in the patients suffering from septicemia. METHODS: AIM2, NLRC4 and TLR4 mRNA levels were evaluated in the 40 patients suffering from septicemia and 40 healthy controls using Real-Time PCR technique. RESULTS: Data analysis revealed that, although NLRC4 expression decreased, TLR4 and AIM2 levels significantly increased in the patients suffering from septicemia. Gender and infection with various bacteria did not affect expression of AIM2, NLRC4 and TLR4. CONCLUSIONS: It appears that septicemia can be limited by immune responses in AIM2 and TLR4 dependent manner. The potential roles played by bacteria to down-regulation of NLRC4 need to be evaluated by further investigations.

Gut Microbiota and IL-17A: Physiological and Pathological Responses.

IL-17A is a cytokine which is produced by several immune and non-immune cells. The cytokine plays dual roles from protection from microbes and protection from pro-inflammatory based diseases to induction of the pro-inflammatory based diseases. The main mechanisms which lead to the controversial roles of IL-17A are yet to be clarified. Gut microbiota (GM) are the resident probiotic bacteria in the gastrointestinal tracts which have been introduced as a plausible regulator of IL-17A production and functions. This review article describes the recent information regarding the roles played by GM in determination of IL-17A functions outcome.

Association of BK Virus Infection with CXCL11 Gene Expression and Protein Levels in Kidney Transplant Patients.

OBJECTIVES: It has been hypothesized that BK polyomavirus infection leads to nephropathy in kidney transplant patients via various plausible mechanisms, such as stimulation of chemokines. The CXCL11 gene may also play a role in BK polyomavirus-associated nephropathy. Our aim was to compare expression levels of CXCL11 in BK polyomavirus-infected versus noninfected kidney transplant patients with nephropathy and healthy controls. MATERIALS AND METHODS: We performed a cross-sectional study of 58 kidney transplant patients with the risk of BK polyomavirus infection; these patients were subgrouped as BK polyomavirus-infected (23 patients) and noninfected (35 patients). We also enrolled 30 healthy patients as controls in this study. The BK polyomavirus genome load was evaluated using a quantitative real-time polymerase chain reaction protocol in kidney transplant patients. We analyzed CXCL11 gene expression and protein levels using in-house SYBR green real-time polymerase chain reaction and enzyme-linked immunosorbent assay protocols. RESULTS: The expression level of the CXCL11 gene was increased 22.37 ± 23.1-fold in BK polyomavirus-infected kidney recipients and 12 ± 24-fold in noninfected patients versus that shown in controls. CONCLUSION: From these results, we concluded that BK polyomavirus infection can induce CXCL11 gene expression in kidney transplant patients compared with that shown in patients without BK infection and healthy patients. However, further studies are needed to determine the accurate counteraction between BK polyomavirus infection and CXCL11 in kidney transplant patients.

Toll-like receptor 2 and its roles in immune responses against Legionella pneumophila.

Legionella pneumophila (L. pneumophila) is an intracellular bacterium which can be survived in the human macrophages phagosomes. The infectious agent is cleared in some cases and survived in others. The main mechanisms responsible for survival of L. pneumophila are yet to be clarified. It has been reported that innate immunity plays key roles in limitation and also eradication of bacterial infections. Toll like receptor 2 (TLR2) is an important cell membrane receptor which recognizes a wide range of bacterial antigens entitled pathogen associated molecular patterns (PAMPs). The aim of the current review article is to present recent data regarding the roles of TLR2 in induction of immune responses and consequently eradication of L. pneumophila. Additionally, the main mechanisms used by L. pneumophila to overcome TLR2 dependent immune responses are discussed in this review article.

Seroprevalence of Anti-Toxoplasma Gondii Antibodies in Healthy Voluntary Blood Donors from Mashhad City, Iran.

OBJECTIVE: The present investigation aims to evaluate the prevalence of IgM and IgG anti-T. gondii antibodies and the associated risk factors among healthy blood donors in Mashhad city, Razavi Khorasan province, Iran. METHODS: We screened a total of 500 serum samples by census method from apparently healthy blood donors of the Mashhad Blood Transfusion Organization (MBTO) for IgG and IgM anti-T. gondii antibodies by enzyme linked immunosorbent assay (ELISA). RESULTS: We found that 29.6%, 25%, 1.4%, and 3.2% of tested donors were positive for anti-T. gondii antibodies, only IgG antibody, both IgM and IgG, and IgM antibody alone, respectively. Several risk factors which were significantly related to T. gondii seropositivity in the univariate analysis at P < 0.05 included female gender (OR = 3.222, P < 0.001), age more than 40 years (P = 0.026), and sausage/hot dog consumption (OR = 4.472, P < 0.001). CONCLUSIONS: The results of this study can be a warning for blood transfusion organizations to pay special attention to toxoplasmosis among blood donors and also design screening programs for prevention of transfusion-transmitted toxoplasmosis.

Pseudomonas aeruginosa quorum sensing modulates immune responses: An updated review article.

Pseudomonas aeruginosa is an opportunistic bacterium which induces some complications in immunocompromised patients. Pseudomonas aeruginosa is a quorum-sensing using bacterium which regulates its genes expression. The bacterium uses two famous pathways for quorum sensing entitled LasI/LasR and RhlI/RhlR systems. It has been documented that the bacteria which use quorum sensing are able to overcome immune responses. This review article aims to present recent information regarding the effects of Pseudomonas aeruginosa quorum sensing systems on the host immune responses.

Tumor growth factor-ß is an important factor for immunosuppression and tumorgenesis in Polyoma BK virus infection; a systematic review article.

Polyoma BK virus (PBK) is a prevalent human specific virus and the cause of several malignancies in human. The main mechanisms used by PBK to induce/stimulate human cancers are yet to be clarified but it has been proposed that PBK may use several mechanisms to induce/stimulate cancers in human including attenuation of immune responses via up-regulation of immunosuppressor molecules. Transforming growth factor beta (TGF-ß) is a key multifunctional factor from modulation of immunosurveillance to angiogenesis. The key roles of TGF-ß in the progression of Th17 and T regulatory subsets, the most important immune cells involved in development of cancers, have been demonstrated. Thus, this review article aims to describe the mechanisms used by PBK in induction/stimulation of human cancers in TGF-ß dependent manner..

IL-2 and polyoma BK virus infection; A systematic review article.

It has been demonstrated that IL-2 plays a dual role in induction/suppression of immune responses via activation of conventional and regulatory T lymphocytes, respectively. IL-2 contacts complete IL-2 receptor (IL-2R) which contains CD25 (α chain) on the antigen specific activated T helper and cytotoxic lymphocytes and also T regulatory cells. Additionally, previous investigations revealed that polyoma BK virus (PBK) reactivation and induction of PBK associated nephropathy (PBKAN) is a main complication following renal transplantation. Based on the important dual roles played by IL-2 in the immune responses, it may be hypothesized that IL-2/IL-2R interaction could be considered a potential mechanism against/toward PBK reactivation and also PBKAN. Accordingly, the aim of the current review article is to determine the roles of IL-2 IL-2/IL-2R interaction in PBK reactivation and PBKAN complications.