Navid Dashti; Forough Golsaz-Shirazi; Mahmood Jeddi-Tehrani; Amir-Hassan Zarnani; Mohammad Mehdi Amiri; Fazel Shokri
Abstract
Background: Since the outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several vaccine candidates have been developed within a short period of time. Although the potency of these vaccines was evaluated individually, their comparative potency was not comprehensively ...
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Background: Since the outbreak of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), several vaccine candidates have been developed within a short period of time. Although the potency of these vaccines was evaluated individually, their comparative potency was not comprehensively evaluated.Objective: To compare the immunogenicity and neutralization efficacy of four approved COVID-19 vaccines in Iran, including: PastoCovac Plus, Sinopharm, SpikoGen, and Noora in BALB/c mice.Methods: Different groups of female BALB/c mice were vaccinated with three doses of each vaccine. The serum levels of antibodies against the viral receptor binding domain (anti-RBD) and spike (anti-spike) protein as well as the vaccine formulation (anti-vaccine) were evaluated using enzyme-linked immunosorbent assay (ELISA). The neutralization efficacy of these four vaccines was assessed through four neutralization assays: conventional virus neutralization test (cVNT), pseudotype virus neutralization test (pVNT), surrogate virus neutralization test (sVNT), and inhibition flow cytometry.Results: All four vaccines induced seroconversion in vaccinated animals. All vaccines successfully induced high levels of anti-vaccine antibody; however, PastoCovac Plus and Sinopharm vaccines induced significantly higher levels of anti-RBD antibody titer compared to Noora and SpikoGen. Moreover, the results of the antibody response were corroborated by the virus neutralization tests, which revealed very weak neutralization potency by Noora and SpikoGen in all tests.Conclusion: Our results indicate significant immunogenicity and neutralization efficacy induced by PastoCovac Plus and Sinopharm, but not by Noora and SpikoGen. This suggests the need for additional comparative assessment of the potency and efficacy of these four vaccines in vaccinated subjects.
Masoud Hassanzadeh Makoui; Maryam Mobini; Jalal Khoshnoodi; Tannaz Bahadori; Forough Golsaz-Shirazi; Hedieh Moradi Tabriz; Zahra Madjd; Mahmood Jeddi-Tehrani; Amir-Hassan Zarnani; Mohammad Mehdi Amiri; Fazel Shokri
Abstract
Background: Ki67 and P53 are important diagnostic and prognostic biomarkers expressed in several cancers. The current standard method for evaluating Ki67 and P53 in cancer tissues is immunohistochemistry (IHC), and having highly sensitive monoclonal antibodies against these biomarkers is necessary for ...
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Background: Ki67 and P53 are important diagnostic and prognostic biomarkers expressed in several cancers. The current standard method for evaluating Ki67 and P53 in cancer tissues is immunohistochemistry (IHC), and having highly sensitive monoclonal antibodies against these biomarkers is necessary for an accurate diagnosis in the IHC test.Objective: To generate and characterize novel monoclonal antibodies (mAbs) against human Ki67 and P53 antigens for IHC purposes.Methods: Ki67 and P53-specific mAbs were produced by the hybridoma method and screened by enzyme-linked immunosorbent assay (ELISA) and IHC techniques. Selected mAbs were characterized using Western blot and flow cytometry, and their affinities and isotypes were determined by ELISA. Moreover, using the IHC technique in 200 breast cancer tissue samples, we assessed the specificity, sensitivity, and accuracy of the produced mAbs.Results: Two anti-Ki67 (2C2 and 2H1) and three anti-P53 mAbs (2A6, 2G4, and 1G10) showed strong reactivity to their target antigens in IHC. The selected mAbs were also able to recognize their targets by flow cytometry as well as Western blotting using human tumor cell lines expressing these antigens. The specificity, sensitivity, and accuracy calculated for clone 2H1 were 94.2%, 99.0%, and 96.6%, and for clone 2A6 were 97.3%, 98.1%, and 97.5%, respectively. Using these two monoclonal antibodies, we found a significant correlation between Ki67 and P53 overexpression and lymph node metastasis in patients with breast cancer.Conclusion: The present study showed that the novel anti-Ki67 and anti-P53 mAbs could recognize their respective antigens with high specificity and sensitivity and therefore can be used in prognostic studies.
Hamzeh Sarvnaz; Sahar Asadi-Asadabad; Mohammad Mehdi Amiri; Mojgan Ghaedi; Ulrike Protzer; Mahmood Jeddi-Tehrani; Forough Golsaz-Shirazi; Fazel Shokri
Abstract
Background: Human polyclonal plasma-derived hepatitis B immunoglobulin (HBIG) is currently used for immunoprophylaxis of HBV infection. The development of virus-neutralizing monoclonal antibodies (MAbs) requires the use of optimized cell culture systems supporting HBV infection.Objective: This study ...
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Background: Human polyclonal plasma-derived hepatitis B immunoglobulin (HBIG) is currently used for immunoprophylaxis of HBV infection. The development of virus-neutralizing monoclonal antibodies (MAbs) requires the use of optimized cell culture systems supporting HBV infection.Objective: This study aims to optimize the hepatitis B virus infectivity of NTCP-reconstituted HepG2 (HepG2-NTCP) cells to establish an efficient system to evaluate the HBV-neutralizing effect of anti-HBs MAbs.Methods: Serum-derived HBV (sHBV) and cell culture-derived HBV (ccHBV) were simultaneously used for the optimization of HBV infection in HepG2-NTCP cells by applying different modifications.Results: Our results for the first time showed that in addition to human serum, monkey serum could significantly improve ccHBV infection, while fetal and adult bovine serum as well as duck and sheep serum did not have a promotive effect. In addition, sHBV and ccHBV infectivity are largely similar except that adding 5% of PEG, which is commonly used to improve in vitro infection of ccHBV, significantly reduced sHBV infection. We showed that a combination of spinoculation, trypsinization, and also adding human or monkey serum to HBV inoculum could significantly improve the permissivity of HepG2-NTCP cells to HBV infection compared with individual strategies. All anti-HBs MAbs were able to successfully neutralize both ccHBV and sHBV infection in our optimized in vitro system.Conclusion: Our study suggests different strategies for improving ccHBV and sHBV infection in HepG2-NTCP cells. This cell culture-based system allows assessment of HBV neutralizing MAbs and may also prove to be valuable for the analysis of other HBV neutralizing therapeutics.
Sayed Mahdi Marashi; Shima Izadi; Seyed Reza Najafizadeh; Ahmad Nejati; Majid Teymoori-Rad; Shohreh Shahmahmoodi; Forough Golsaz-Shirazi; Fazel Shokri
Abstract
Background: Systemic lupus erythematous (SLE) is a multisystem autoimmune disorder. While studying the pathogenesis of SLE is prevalent, both infectious and non-infectious elements are regarded to exert an important impact on the disease's development. Objective: To explore the overall status of EBV, ...
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Background: Systemic lupus erythematous (SLE) is a multisystem autoimmune disorder. While studying the pathogenesis of SLE is prevalent, both infectious and non-infectious elements are regarded to exert an important impact on the disease's development. Objective: To explore the overall status of EBV, TLR7, TLR9, and IFN-α gene expression in 32 patients suffering from SLE and 32 healthy controls. Methods: Plasma and PBMCs were separated from fresh whole blood. To measure EBV DNA load and mRNA levels of IFN-a, TLR-7 and9 in PBMCs, molecular techniques were employed. The production of IFN-α, ds-DNA IgG antibody, and EBNA-1 IgG levels were also measured in plasma by ELISA. Results: SLE patients showed significantly higher EBV load (p=0.001) and transcriptional levels of TLR7 (p=0.0001), IFN-α (p=0.0001), and TLR9 (p=0.0001) than controls. Moreover, the plasma levels of IFN-α (p=0.0002) and EBNA-1specific IgG antibodies (p=0.01) were significantly higher in SLE patients. Conclusion: The results stressed on the potential role of EBV infection and TLRs in SLE patients although more research is needed to determine the global impact that EBV infection can have on immune signature in patients with SLE.
Fatemeh Hajighasemi; Soheila Gharagozlou; Nasrin Moheghi; Roya Ghods; Jalal Khoshnoodi; Fazel Shokri
Volume 2, Issue 3 , September 2005, , Pages 125-133
Abstract
Background: There are two subclasses of human IgA (IgA1 and IgA2) that differ in antigenic properties and in chemical composition. The constant domains of α1 and α2 heavy chains have >95% sequence homology though major structural differences exist in the hinge region. Quantitation of IgA ...
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Background: There are two subclasses of human IgA (IgA1 and IgA2) that differ in antigenic properties and in chemical composition. The constant domains of α1 and α2 heavy chains have >95% sequence homology though major structural differences exist in the hinge region. Quantitation of IgA subclass levels depends on the availability of monoclonal antibodies (MAbs) specific for conserved conformational or linear epitopes restricted to each subclass. Objective: To produce, select and characterize monoclonal antibodies specific for human IgA2. Methods: Splenocytes from BALB/C mice immunized with a human IgA2 myeloma protein were fused with SP2/0 myeloma cells. Fused cells were grown in hypoxanthine, aminopterine and thymidine (HAT) selective medium and cloned by limiting dilution assay. Antibody (Ab) secreting cells were screened by enzyme-linked immunosorbent assay (ELISA) and the specificity of secreted MAbs was further analyzed, using a panel of purified myeloma proteins and some animal sera by ELISA and immunoblotting. The affinity constant (Kaff) was also determined by ELISA. Results: Four murine hybridoma clones designated 2F20G5, 2F20B5, 3F20E3 and 6F20H11 were obtained that secreted MAbs specific for the human IgA2. 2F20G5 and 6F20H11 MAbs react with linear epitope(s) while 2F20B5 and 3F20E3 react with conformational epitope(s) located to human IgA2 subclass. 2F20G5 MAb displays a weak cross-reactivity with monkey and rabbit sera and a strong cross-reactivity with cat and dog sera while the other three MAbs showed no cross-reactivity with the animal sera tested. Conclusion: These MAbs, especially 6F20H11 with high affinity constant (6.03 ×109 M-1) are useful tools for quantitation of human IgA2 subclass levels in various diseases. Cross-reactivity of 2F20G5 MAb with some animalsera suggests phylogenic conservation ofthe epitope recognized by this MAb.
Abdollah Jafarzadeh; Jalal Khoshnoodi; Shayesteh Ghorbani; Saleh Mohaghegh Hazrati; Babak Faraj Mazaheri; Fazel Shokri
Volume 1, Issue 2 , September 2004, , Pages 98-104
Abstract
Objective: To compare immunogenicity of a recombinant hepatitis B (HB) vaccine in two groups of neonates born in two cities of Iran with different geographic and ethnic backgrounds. Materials and Methods: Ten micrograms of a recombinant HB vaccine was administered under field condition to Iranian ...
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Objective: To compare immunogenicity of a recombinant hepatitis B (HB) vaccine in two groups of neonates born in two cities of Iran with different geographic and ethnic backgrounds. Materials and Methods: Ten micrograms of a recombinant HB vaccine was administered under field condition to Iranian healthy neonates at 0, 1.5 and 9 months intervals. The subjects consisted of two groups of 290 and 231 neonates selected from two cities located at north-west (Urmia) and south-east (Kerman) of Iran, respectively. The level of anti-HBs antibody was quantitated in serum 2-4 weeks after administration of the last vaccine dose, by sandwich ELISA. Results: A higher seroprotection rate (anti-HBs> 10 IU/L) (98.3% vs. 96.1%) and significantly increased serum anti- HBs antibody titer (11869 vs. 6104 IU/L) (P<0.001) were induced in vaccinated neonates from Urmia city, compared to those born in Kerman. Conclusion: These findings suggest contribution of ethnic and/or environmental factors in the antibody response to recombinant HB vaccine in human.
