Forough Golsaz Shirazi; Mohammad Mehdi Amiri; Hamed Mohammadi; Ali Ahmad Bayat; Azam Roohi; Jalal Khoshnoodi; Amir Hassan Zarnani; Mahmood Jeddi-Tehrani; Gholam Ali Kardar; Fazel Shokri
Volume 10, Issue 3 , September 2013, , Pages 127-138
Abstract
Background: The antibody response to hepatitis B surface antigen (HBsAg) controls hepatitis B virus infection. The "a" determinant of HBsAg is the most important target for protective antibody response, diagnosis and immunoprophylaxis. Mutations in this area may induce immune escape mutants and affect ...
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Background: The antibody response to hepatitis B surface antigen (HBsAg) controls hepatitis B virus infection. The "a" determinant of HBsAg is the most important target for protective antibody response, diagnosis and immunoprophylaxis. Mutations in this area may induce immune escape mutants and affect the performance of HBsAg assays. Objectives: To construct clinically relevant recombinant mutant forms of HBsAg and assessment of their reactivity with anti-HBs monoclonal antibodies (MAbs). Methods: Wild type (wt) and mutant (mt) HBsAg genes were constructed by site directed mutagenesis and SEOing PCR. The amplified genes were inserted into pCMV6-neo plasmid and transfected in CHO cell line. The expression of wt- and mtHBsAg was assessed by commercial ELISA assays and stable cells were established and cloned by limiting dilution. The recombinant mutants were further characterized using a panel of anti-HBs monoclonal antibodies (MAbs) and the pattern of their reactivity was assessed by ELISA. Results: Ten HBsAg mutants having single mutation within the "a" determinant including P120E, T123N, Q129H, M133L, K141E, P142S, D144A, G145R, N146S and C147S together with a wt form were successfully constructed and expressed in CHO cells. Reactivity of anti-HBs MAbs with mtHBsAgs displayed different patterns. The effect of mutations on antibody binding differed depending on the amino acid involved and its location within the ‘‘a’’ determinant. Mutation at amino acids 123 and 145 resulted in either complete loss or significant reduction of binding to all anti-HBs MAbs. Conclusion: Our panel of mtHBsAgs is a valuable tool for assessment of the antibody response to HBV escape mutants and may have substantial implications in HBV immunological diagnostics.
Mohammad Jafar Mahmoudi; Maryam Mahmoudi; Fereydoon Siassi; Fazel Shokri; Mohammad Reza Eshraghian; Amir Hassan Zamani; Reza Chahardoli; Mona Hedayat; Jalal Khoshnoodi; Hashem Nayeri; Nima Rezaei; Ali-Akbar Saboor-Yaraghi
Volume 8, Issue 1 , March 2011, , Pages 27-33
Abstract
Background: Atherosclerosis, a chronic inflammatory disease of the vessel wall is characterized by local and systemic immune responses to a variety of antigens. Oxidized low-density lipoprotein (oxLDL) is considered as an important determining factor in the pathogenesis of atherosclerosis. Objective: ...
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Background: Atherosclerosis, a chronic inflammatory disease of the vessel wall is characterized by local and systemic immune responses to a variety of antigens. Oxidized low-density lipoprotein (oxLDL) is considered as an important determining factor in the pathogenesis of atherosclerosis. Objective: The purpose of this study was to investigate the degree of peripheral blood mononuclear cells (PBMC) vulnerability to in vitro oxLDL-induced cytotoxicity from atherosclerotic patients in comparison to healthy individuals. Methods: Thirty patients with atherosclerotic lesions, confirmed by angiography, and 30 matched healthy individuals were investigated. PBMC was prepared from individuals' blood samples which were further stimulated with low dose (1 μg/mL) and high dose (50 μg/mL) of extensively oxidized LDL. MTT assay was utilized to measure cell viability and proliferation. Stimulation index (SI) was calculated as mean ratio of optical density (OD) of the stimulated cells divided by OD of untreated cells. Results: Low dose oxLDL treatment caused no significant proliferative or cytotoxic effect in the control group; however, similar treatment caused significant cytotoxic effect in the patient group compared to the controls (p=0.026). High dose oxLDL treatment induced more significant cytotoxicity in the patient compared to the control group (p=0.006). Comparison of the SI between the two groups of patients and controls showed significantly lower index by either the low (p=0.03) or the high dose (p<0.001) oxLDL in the patients compared to the controls. Conclusions: PBMC from patients with atherosclerosis showed increased susceptibility to oxLDL-induced cytotoxicity. Our results imply that prolonged exposure to elevated levels of circulating oxLDL could weaken the cellular defense mechanisms by progressive depletion of the pool of antiapoptotic proteins, rendering the cells more vulnerable to oxLDL-induced cell death.
Hossein Asgarian Omran; Mahdi Shabani; Tahereh Shahrestani; Abdolfattah Sarafnejad; Jalal Khoshnoodi; Parvaneh Vossough; Mohammad Faranoush; Ramzan A. Sharifian; Mahmood Jeddi-Tehrani; Hodjatallah Rabbani; Fazel Shokri
Volume 4, Issue 1 , March 2007, , Pages 15-25
Abstract
Background: Immunophenotypic characterization of the leukemic cells has been widely used as a tool for diagnosis, classification, stratification and prognosis of leukaemia. Objective: To investigate the immunophenotypic subtype profiles of Iranian patients with acute lymphoblastic leukemia (ALL) and ...
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Background: Immunophenotypic characterization of the leukemic cells has been widely used as a tool for diagnosis, classification, stratification and prognosis of leukaemia. Objective: To investigate the immunophenotypic subtype profiles of Iranian patients with acute lymphoblastic leukemia (ALL) and its association to disease outcome. Methods: In this study, a total of 60 Iranian patients with ALL were immunophenotyped by flow cytometry using a panel of monoclonal antibodies specific for CD2, CD3, CD5, CD10, CD13, CD14, CD19, CD20, CD33, CD34, CD45, HLA-DR and TdT molecules. Results: The samples were initially categorized into T-ALL (n=9), B-ALL (n=50) and mixed lineage (n=1) based on the expression patterns of CD3 and CD19 molecules. B-ALL patients could further be classified into four subtypes, including Pro-B (n=7, 11.7%), Pre-B I (n=28, 46.7%), Pre-B II (n=13, 21.7%) and immature/mature B cells (n=2, 3.3%) on the basis of expression of CD10, CD19, CD20, HLA-DR and TdT. Clinical manifestations and laboratory findings of the patients did not reveal association with immunophenotypic sub-types of ALL, with the exception of mediastinal mass and WBC count at the time of diag-nosis which were found to be significantly higher in patients with T-ALL compared with B-ALL (p=0.001 and 0.014), respectively. Conclusion: Our results indicate that overall the immunophenotypic profile of Iranian ALL patients is similar to previous reports and it might be used for monitoring of minimal residual disease and prognosis.
Hossein Asgarian; Mahdi Shabani; Parvaneh Vosoogh; Ramazan Ali Sharifian; Soheila Gharagozlou; Jalal Khoshnoodi; Tahereh Shahrestani; Mahin Kordmahin; Abdolfattah Sarrafnejad; Mahmood Jeddi Tehrani; Hodjatallah Rabbani; Fazel Shokri
Volume 2, Issue 4 , December 2005, , Pages 182-190
Abstract
Background: The Wilm’s tumor gene 1 (WT1) encodes a zinc finger transcription factor that is inactivated in a subset of Wilm’s tumors. It plays a crucial role in growth, proliferation and development of some embryonic and adult organs. WT1 is expressed as a tumor associated antigen (TAA) ...
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Background: The Wilm’s tumor gene 1 (WT1) encodes a zinc finger transcription factor that is inactivated in a subset of Wilm’s tumors. It plays a crucial role in growth, proliferation and development of some embryonic and adult organs. WT1 is expressed as a tumor associated antigen (TAA) in various types of solid and hematopoietic malignancies and can be employed as a useful marker for targeted immunotherapy and monitoring of minimal residual disease (MRD). Objective: To investigate the profile of WT1 gene expression in Iranian patients with acute myeloblastic leukemia. Methods: RT-PCR method was used to determine the WT1 gene expression in bone marrow (BM) and/or peripheral blood (PB) samples from 11 patients with AML and PB samples of 36 normal subjects. Isolated cells from all patients were immunophenotyped by flow cytometry. Results: The leukemic cells from 10 patients (91%) were found moderately or strongly positive for WT1 expression whereas only 3 out of 36 normal subjects expressed WT1 at very low levels. A highly significant correlation was observed for WT1 expression between paired BM and PB samples of the AML patients. Conclusion: Our results indicate that WT1 is expressed in the majority of Iranian AML patients and may be employed for screening and monitoring of minimal residual disease in these patients.
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.
