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Background: Iranian Lizard Leishmania (I.L.L) is a nonpathogenic Leishmania strain. Due to its advantages, several recombinant proteins have been produced in this host. However, I.L.L shows a lower yield of recombinant protein expression compared to other commercial hosts. Considering the role of protease enzymes in protein digestion, we selected cysteine protease B (CPB) to investigate its impact on recombinant protein yield in I.L.L. Methods: we generated gene knockouts by utilizing homologous recombination (HR) and CRISPR methods. To assess the efficacy of the designed construct, we compared the yield of recombinant human factor VII (rhFVII) production between cells transfected with the pLEXSY-hyg2-FVII vector and the CMVpromoter-based construct (pF7cmvneo). Results: The knockout of a single CPB gene allele through the HR method or the complete knockout of all alleles through the CRISPR method led to cell death. This outcome suggests that even the deletion of a single CPB gene allele diminishes the protein to a level insufficient for the survival of I.L.L, indicating a critical dependency on the presence of this protein for the organism's viability. rhFVII exhibited a greater expression yield with the pLEXSY construct compared to the pF7cmvneo construct in I.L.L. The lower expression rate of pF7cmvneo may be influenced by epigenetic factors related to the CPC gene or the RNA polymerase used for the expression of that promoter. Conclusion: Therefore, considering alternative integration targets for CMVpromoter-based constructs and incorporating UTR sequences of I.L.L highexpression proteins in the vector may enhance recombinant protein expression rates. [ABSTRACT FROM AUTHOR]

The treatment of type 1 diabetes through islet cell transplantation is a complex process, facing challenges such as allograft rejections and a limited supply of donors. One potential solution is to utilize the liver as an alternative for natural insulin production, as hepatocytes can secrete proteins and respond to glucose levels. Recent research has shown promising results in using mesenchymal stem cells as a potential cure for diabetes. The study utilized a diabetic rat model, confirmed through blood sugar measurement. A plasmid vector was designed with specific genetic components, synthesized by biotech company, and then Inserted vector into a plasmid with resistance genes and bacterial origin. Bone marrow‐derived mesenchymal stem cells (BM‐MSCs) were cultured and transfected with the plasmid using Lipofectamine 3000. Polymerase chain reaction was employed to confirm successful transfection using specific primers. For the animal study, 30 male Wistar rats were divided into six groups, each comprising five rats. The control group did not receive any treatment, while the second group received MSCs via Portal Vein Injection. The third group received MSCs transfected with a specific construct via Portal Vein Injection. The fourth group was induced to develop diabetes through streptozotocin (STZ) injection, the fifth group developed diabetes and received untransfected MSCs via Portal Vein Injection, and the sixth group received MSCs transfected with the specific construct via Portal Vein Injection. To manage Pain, appropriate pain control was administered to the rats for 3 days after the surgery. Fixed liver tissues obtained from the euthanized rats were utilized for immunohistochemistry. In this study, immunohistochemical techniques were used to examine insulin expression in different groups of rats. The control groups showed high levels of insulin expression, while the diabetic groups exhibited lower expression. However, there was a significant difference between the diabetic groups treated with MSC and transgenic MSC cells. All groups had similar baseline glucose levels, but the diabetic groups showed a significant increase after STZ injection, whereas the control and MSC groups did not. Postintervention, both the control and MSC groups had similar glucose levels to the post‐STZ levels. However, diabetes‐induced groups experienced a significant decrease in glucose levels, with the transfected MSCs showing a greater decrease than the untransfected MSCs. The study suggested that treatment with MSCs, especially transfected ones, can effectively reduce glucose levels in rats with diabetes. In this research, rat BM‐MSCs were utilized to create insulin‐producing mesenchymal cells with glucose‐sensitive insulin expression. The cells were transferred to the liver of diabetic rats via portal vein injection, leading to an increase in insulin expression. This study proposes a novel approach for cell therapy and delivery in the treatment of type 1 diabetes. Significance Statement: Type 1 diabetes arises from autoimmune destruction of pancreatic β cells, leading to insulin deficiency. Cell therapy, presents a promising avenue. cells can be genetically engineered to produce insulin in response to glucose fluctuations. Mesenchymal stem cells are potential candidates for generating insulin‐producing cells. This study employed a novel approach, genetically engineered using a plasmid vector with glucose‐responsive elements in bone marrow‐derived mesenchymal stem cells and cell transfer to rat liver through portal vein injection. Differing from conventional methodologies, this research utilized undifferentiated rat BM‐MSCs. The hypothesis revolved around the potential of rat BM‐MSCs to migrate into the rat liver via the Portal Vein Injection method, offering a distinctive perspective on diabetes treatment. [ABSTRACT FROM AUTHOR]

Background: A lizard Leishmania has been isolated from a lizard (Agama agilis) in Iran. Its genome sequence has not been determined, so far. Methods: The study was done at Shahid Beheshti University of Medical Sciences, Tehran, Iran in 2017-2023. Leishmania promastigotes were cultured in RPMI1640 culture medium and collected at logarithmic phase by centrigugation. Parasite RNA was extracted by the Qiagene standard kit and its quantity and quality was determined and sequenced by NGS method with Illumina PE machine at BGI Company (China). Results: The number of 8316 mRNA, 83 tRNA, 63 rRNA, 83 ncRNA, 5 snRNA, 1039 snoRNA, 36 region, and 3 repeat regions, 8343 CDS, 9597 Exon and 9292 Genes were identified in promastigote of Iranian lizard Leishmania. Conclusion: Genomic elements of Iranian lizards Leishmania (with unique characteristics) were determined and identified by NGS system. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]