Avicenna Journal of Medical Biotechnology
Year:2017 | Volume:9 | Issue:2|Papers Count:9

Islamic Iran, on the Horizon of the 2025 Outlook Document, should obtain first regional rank in economic, social, scientific, and cultural domains. Country’s noticeable growth in scientific production and dynamic movement of Iranian scientists and specialists in scientific frontiers resulted in the country earning first rank in regional scientific production, leaving behind Turkey, in the year 2011, 14 years ahead of the Horizontal Outlook prediction.

Cartilage is an avascular, aneural, and alymphatic connective tissue with a limited capacity caused by low mitotic activity of its resident cells, chondrocytes. Natural repair of full thickness cartilage defects usually leads to the formation of fibrocartilage with lower function and mechanical force compared with the original hyaline cartilage and further deterioration can occur. Tissue engineering and regenerative medicine is a promising strategy to repair bone and articular cartilage defects and rehabilitate joint functions by focusing on the optimal combination of cells, material scaffolds, and signaling molecules. The unique physical and topographical properties of nanofibrous structures allow them to mimic the extracellular matrix of native cartilage, making an appropriate resemblance to induce cartilage tissue regeneration and reconstruction. To improve simulation of native cartilage, the incorporation of nanofibrous scaffolds with suitable corresponsive cells could be effective. In this review article, an attempt was made to present the current state of cartilage tissue engineering using nanofibrous scaffolds and stem cells as high proliferative immune privilege cells with chondrogenic differentiation ability. The comprehensive information was retrieved by search of relevant subject headings in Medline/Pubmed and Elsevier databases.

Background: Silymarin is a flavonolignan that has been the subject of research to evaluate the beneficial properties for decades. Silymarin has been known for its potent cytoprotective, hepatoprotective and antioxidant activities. The goal of the present study was to gain a deeper understanding of possible molecular mechanisms of apoptosis of the injuries induced by silymarin on BALB/c mice fetuses.Methods: The present experimental study was carried out in virgin female BALB/c mice. The animals were divided randomly into 4 groups. Three test groups were injected intraperitoneally with silymarin at doses of 50, 100 and 200mg/kg/day during gestational days 6-15. The control group received the solvent by the same route at equivalent volume. Western blot analysis was conducted to determine the levels of caspase-3 and caspase-8 in fetal heart, kidney, lungs and brain tissue.Results: The results of this study showed that silymarin administration during organogenesis at doses of 50, 100 and 200mg/kg can significantly increase the protein levels of caspase-3 and 8 in heart, kidneys and brain tissues of mice fetuses compared with control group (p<0.001). Silymarin exposure could not change the level of apoptotic markers in fetal lung tissue.Conclusion: According to the results, programmed cell death, especially via the intrinsic pathway, plays a pivotal role in the pathogenesis of silymarin-induced malformations in some tissue including heart, kidneys and brain. More studies are needed to determine other molecular mechanisms underlying silymarin- induced embryo toxicity.

Background: Autophagy as a cellular pathway facilitates several immune responses against infection. It also eliminates invading pathogens through transferring content between the cytosol and the lysosomal vesicles and contributes to the cross-presentation of exogenous antigens to T lymphocytesvia MHC class I pathway. Autophagy induction is one of the main targets for new drugs and future vaccine formulations.Nanoparticles are one of the candidates for autophagy induction. Cysteine Peptidase A (CPA) and Cysteine Peptidase B (CPB) are two members of papain family (Clan CA, family C1) enzyme that have been considered as a virulence factor of Leishmania (L.) major, making them suitable vaccine candidates. In this research, Leishmania major cysteine peptidase A and B (CPA and CPB) conjugation to alpha alumina nanoparticle was the main focus and their entrance efficacy to macrophages was assessed.Methods: For this purpose, CPA and CPB genes were cloned in expression vectors. Related proteins were extracted from transformed Escherichia coli (E. coli) and purified using Ni affinity column. Alpha alumina nanoparticles were conjugated to CPA/CPB proteins using Aldehyde/Hydrazine Reaction. Autophagy induction in macrophages was assessed using acridine orange staining.Results: CPA/CPB protein loading to nanoparticles was confirmed by Fourier Transform Infrared Spectroscopy.α-alumina conjugated CPA/CPB antigen uptake by macrophages at different concentrations was confirmed using fluorescence microscope and flow cytometry. Highly efficient CPA/CPB protein loading toα-alumina nanoparticles and rapid internalization to macrophages introduced these nanocarriers as a delivery tool. Acridine orange staining demonstrated higher autophagy induction in CPA/CPB protein conjugated withα-alumina nanoparticles.Conclusion: a-alumina nanoparticles may be a promising adjuvant in the development of therapeutic leishmania vaccines through antigen delivery to intracellular compartments, induction of autophagy and cross presentation to CD8 lymphocytes.

Background: Lipase enzymes have applications in a wide range of industries. A crucial determining factor of industrial prices of these enzymes is the culture media composition that is constantly under review by researchers. In this work, for maximum lipase production byBacillus sp. ZR-5, culture media compositions were optimized using "one variable at a time" strategy.Methods: For this purpose, the culture medium parameters such as low and high cost carbon and nitrogen sources, substrates and incubation times were evaluated.Results: Maximum lipase activity was achieved after 24 hr of incubation with 1.5% of glucose syrup (1600±69.1u/mg), 1% of fish powder (1238±36.7 u/mg) and olive oil (1407±2.1u/mg) as low cost carbon and nitrogen sources and substrate, respectively.Conclusion: Our results show a significant increase in lipase activity with usage of low cost sources; this could help in reducing the media prices for industrial application of lipase enzyme.

Background: During the last twenty years, the extraction of specific egg yolk (IgY) antibodies from the immunized chickens has been accepted as a useful alternative to the immunization of mammals. The aim of the present study was immunizing the chickens with Human Umbilical Cord Serum (HUCS) and the extraction of specific anti-human globulins (IgG, C3b, and C3d) antibodies from egg yolk in order to obtain polyspecific Coombs reagent.Methods: The novelty of this work was the achievement of a polyclonal reagent through a very cheap alternative method in accordance with all ethical regulations required for obtaining it. Three Leghorn hens (21 weeks old) were immunized four times for a period of 66 days with 20uL of HUCS mixed with PBS/FCA or FIA each time. The extraction of IgY antibodies was performed according to the method of lipid precipitation of yolk and using water soluble fraction as the reagent material. The resulting IgY antibody was characterized by SDS-PAGE and immunoelectrophoresis and tested for the presence of hetero-agglutinins by means of direct agglutination using human erythrocytes of all blood groups treated with 0.1% papain and for indirect Coombs-test to evaluate its specificity to fractions (C3b, C3d, C4d) of human complement and human IgG, respectively.Results: Our findings show, that, the reagent obtained contains IgY and other 3 proteins (SDS-PAGE), and reacts specifically with plasma proteins, that migrate inβ andϒregions. In immunoelectrophoresis, in addition, there is the presence of low heteroagglutinins levels in IgY-preparation (3 lots), and the possibility to produce high amount (more than 500ml/egg) of polyspecific Coombs-reagent in chickens is also discussed.Conclusion: IgY-preparation (3 lots), and the possibility to produce high amount (more than 500ml/egg) of polyspecific Coombs-reagent in chickens with the originality to achieve a polyclonal reagent through a very cheap alternative method in accordance with all ethical regulations required for obtaining it, was also discussed.

Background: The aim of this study was to examine the interaction of dietary food groups and genetic variants of APOA1/APOC3, relative to Metabolic Syndrome (MetS) risk in adults.Methods: In this matched nested case-control study, 414 MetS subjects and 414 controls were selected from among participants of Tehran Lipid and Glucose Study. Dietary intake was assessed with the use of a valid and reliable semi-quantitative food frequency questionnaire. Single Nucleotide Polymorphisms (SNPs), APOA1 (rs670, -75G>A and rs5069, +83C>T/APOC3 rs5128 C3238>G) were genotyped by the conventional polymerase chain reaction and restriction fragment length polymorphism.Results: The mean (SD) of age was 40.7 (13) and 41.2 (13) years in male cases and controls versus 44.0 (11) and 44.0 (12) years in female case and controls. A significant interaction between intake quartiles of the sugar group and APOA1 combined group (GA+AA/CT+TT) SNPs was found; The ORs for these genotype carriers were (1, 0.44, 0.36, 0.23; P trend<0.001) in quartiles of intake, relative to other combined genotypes (P interaction=0.02). MetS risk appeared to be increased significantly in higher quartiles of sweet beverages and fish intakes in the GA+AA/CT+TT/CC genotypes of APOA1/APOC3 SNPs, compared to other genotypes (P interaction=0.01). The combined effect of genotypes of APOC3/APOA1 showed further decrease in MetS risk in higher quartiles of sugar group intakes (OR: 1, 0.24, 0.26, 0.14, P trend=0.001) relative to other combinations (P interaction=0.008).Conclusion: Results obtained demonstrate that some dietary food groups (sugar, fish, and sweet beverages) modulate the effect of APOA1/APOC3 SNPs in relation to MetS risk.

Background: Acute Promyelocytic Leukemia (APL) is a subclass of acute myeloid leukemia. The chromosomal aberration in 95% of APL cases is t (15; 17) (q22; q21), which prevents cell differentiation. Characterization of the underlying molecular lesion is valuable in determining optimal treatment strategy. The goal of this study was to develop a new and powerful Flow- FISH technique to detect the long isoform (L) of PML-RARa fusion transcript in NB4 cell line.Methods: To achieve the best condition for fixation, two different fixatives including 2% paraformaldehyde and 75% ethanol were used.0.2% Triton X-100 and 0.2% saponin were used for the permeabilization step.In hybridization, a wide range of times and temperatures were used and probe was designed in FRET system. Results were confirmed by fluorescent microscope assay and reverse transcription PCR.Results: In the present study, a novel technique was successfully optimized that combines in situ hybridization with flow cytometry to detect the presence of PML-RARa transcript. Using standard fixation and permeabilization protocol of 2% PFA and 0.2% saponin gave the best fluorescent results in flow cytometry. Also, results indicated that the optimum time and temperature for hybridization was 2hr at 42°C. The results of reverse transcription PCR and fluorescent microscopy confirmed the presence of PML-RARa transcript.Conclusion: The concordance between the results of Flow-FISH and those of two other techniques including reverse transcription PCR and FISH indicated that this method would be applicable as a diagnostic test for APL in clinical samples and MRD monitoring.

Background: Among diverse protein purification systems, affinity chromatography is the most attractive one in the purification process of coagulation factors. Coagulation factor VII is a plasma serine protease that has a significant role in natural human hemostasis and its recombinant form such as AryoSevenTM, has been applied in clinical treatment of bleeding disorders. Immunoaffinity chromatography is the purification method of choice that is currently applied in the development of coagulation factor VIIa products. Aptamers as nucleic acid based affinity ligands are more promising than monoclonal antibodies. In addition, DNA aptamers are more acceptable than RNA ones in this regard.Methods: In this study, two of the aptameric DNA oligonucleotides that showed acceptable affinities for purification of coagulation factor VIIa from plasma, were selected to evaluate their affinity against Aryoseven. A serial dilution of fluorescence labeled aptamers was incubated against the concentration of 1nM from Aryoseven.Then, a fluorescence index was calculated according to the fluorescence intensity data measured from test and control samples. The dissociation constant of aptamers was calculated according to the fluorescence index using Prism5 software.Results: Results showed that the binding affinity of the 44 nucleotide aptamer was more than 81 nucleotide aptamer sequence. As a result, this aptamer could be optimized in order to develop aptamer based affinity chromatography process for this form of recombinant coagulation factor VIIa.Discussion: Aptamers with shorter length of sequence could show higher affinity in target binding, as they could adapt more easily to suitable conformation according to target interaction. However, it should be considered that the selectivity of affinity ligands is also important for target purification and analytical applications.