Original Article
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.
Original Article
Fatemeh Vahedi; Naser Taiebi Meibody; Mahdi KianiZadeh; Mahmoud Mahmoudi
Volume 2, Issue 3 , September 2005, Pages 134-140
Abstract
Background: DNA immunization with plasmid DNA encoding bacterial, viral, parasitic and tumor antigens has been reported to trigger protective immunity. Objective: To evaluate the use of a DNA immunization strategy for protection against anthrax, a plasmid was constructed. Methods: The partialsequence ...
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Background: DNA immunization with plasmid DNA encoding bacterial, viral, parasitic and tumor antigens has been reported to trigger protective immunity. Objective: To evaluate the use of a DNA immunization strategy for protection against anthrax, a plasmid was constructed. Methods: The partialsequence of protective antigen of Bacillus anthracis, amino acids 175-764, as a potent immunogenic target was selected. The DNA encoding this segment was utilized in the construction of pcDNA3.1+PA plasmid. After intramuscular injection of rats with pcDNA3.1+PA plasmid, the expression of PA was assessed by RT-PCR and immunohistochemistry at RNA and protein levels, respectively. We also evaluated the presence of anti-PA antibodies in sera of immunized mice with pcDNA3.1+PA construct using immunoblotting. Results: The integrity of pcDNA3.1+PA construct was confirmed with restriction analysis and sequencing. The expression of PA was detected at RNA and protein levels. The presence of anti-PA antibodies in immunized mice with pcDNA3.1+PA construct was also confirmed. Conclusion: Our results indicate that pcDNA3.1+PA eukaryotic expressing vector could express PA antigen, induce antibody response and may be used as a candidate for DNA vaccine against anthrax.
Original Article
Mohammad Hasan Sheikhha; Mehdi Kalantar; Khalid Tobai; John A. Liu Yin
Volume 2, Issue 3 , September 2005, Pages 141-151
Abstract
Background: The glutathione S-transferase (GST) family of metabolising enzymes plays an important role in the detoxification of mutagens and carcinogens. The expression of many of these cancer susceptibility enzymes is genetically polymorphic. An increased frequency of GST-null genotypes has been associated ...
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Background: The glutathione S-transferase (GST) family of metabolising enzymes plays an important role in the detoxification of mutagens and carcinogens. The expression of many of these cancer susceptibility enzymes is genetically polymorphic. An increased frequency of GST-null genotypes has been associated with several malignancies. Objective: To investigate the rate of GSTT1 and GSTM1 null genotypes in AML patients and to determine its importance in prognosis of the disease. Methods: DNA was extracted by phenol/chloroform method from peripheral blood or bone marrow of 180 white Caucasian patients. A multiplex PCR method was used simultaneously to amplify regions of GSTM1, GSTT1, and b-globin genes in genomic DNA. The survival curves were analyzed by the Kaplan-Meier method and compared by the log-rank test (Mantel-Cox) using the SPSS software program. Results: Of the total of 180 patients, 23 cases (12.8%) showed null genotypes in both genes, while in 52 patients (28.9%) both genes were wild-types. GSTM1 null-GSTT1 wild-type was detected in 91 patients (50.6%) and GSTM1 wild-type-GSTT1 null genotype was detected in 14 patients (7.8%). These rates are within the upper limit of the rates detected in the normal European population. There was no significant difference in the overall survival and in disease free survival between different groups. Conclusion: These observations suggest that the inherited absence of the GSTT1 and GSTM1 carcinogen detoxification pathway may be related to carcinogenesis but it is not an important determinant of prognosis in AML.
Original Article
Sousan Farazmand; Dawar Amani; Zohair-Mohammad Hassan
Volume 2, Issue 3 , September 2005, Pages 152-157
Abstract
Background: Alteration in peripheral blood lymphocytes (PBLs) is usually investigated to provide an evidence of the host immune responses to tumor antigens. The tumor infiltrating NK cells interact most closely with the tumor cells and more accurately reflect tumor host interactions. Objective: To analyze ...
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Background: Alteration in peripheral blood lymphocytes (PBLs) is usually investigated to provide an evidence of the host immune responses to tumor antigens. The tumor infiltrating NK cells interact most closely with the tumor cells and more accurately reflect tumor host interactions. Objective: To analyze peripheral blood and tumor associated Natural Killer (NK) cells in patients with breast cancer by immunophenotyping. Methods: Twenty women suffering from breast cancer were examined; 12 of them were confirmed histologically to be invasive ductal carcinoma. PBL and tissue samples from patients and matched control group were processed for analysis by flow cytometry. Results: Results of PBL analysis indicated a significant (P<0.05) increase in both the total number and activated NK cells in invasive ducal carcinoma patients compared to normal controls. No significant differences were noticed in the percent of NK cells and their activation marker expression in intra tumor lesion of the invasive ductal carcinoma and other tumors compared to benign lesions, however a decrease in the total NK number and activated NK cells was observed with progression of the tumor. Conclusion: Data of this investigation conclude that the total and activated NK cell number increase in peripheral blood of patients with breast cancer. The relationship between peripheral blood and intratumor NK cells needs more clarification, however, a decrease in intratumor NK cell number and their activation status occurs with tumor progression.
Original Article
Hossein Abdolrahim-Zadeh; Niloufar Hakkakian; Reza Asadollahi; Behrouz Gharesifard; Jamal Sarvari; Eskandar Kamali-Sarvestani; Abdolrasoul Talei
Volume 2, Issue 3 , September 2005, Pages 158-165
Abstract
Background: IL-10 is an anti-inflammatory cytokine which is involved in tumorigenesis. Over production of IL-10 and elevated number of IL-10 generating mononuclear cells in breast tumor tissue has already been shown. Objective: To determine the association of IL-10 promoter polymorphisms with increased ...
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Background: IL-10 is an anti-inflammatory cytokine which is involved in tumorigenesis. Over production of IL-10 and elevated number of IL-10 generating mononuclear cells in breast tumor tissue has already been shown. Objective: To determine the association of IL-10 promoter polymorphisms with increased risk of breast cancer and its association with breast cancer prognostic factors. Methods: Peripheral blood samples from 275 female breast cancer patients and 320 cancer free controls were used to detect three single nucleotide polymorphisms in IL-10 promoter region ( -1082, -819, -592 ) by PCR method. Results: The frequency of genotypes and alleles of three mentioned regions of IL-10 promoter and their haplotypes (GCC, ATA, and ACC) showed no statistically significant difference between patients and controls. In the case of prognostic factors, progesterone receptor (PR) status exhibited significant relation with -1082 genotypes (P=0.03) and haplotypes (P=0.02). -1082 AA genotype was associated with negative PR expression whereas AG and GG genotypes of this site were positively associated with PR expression. Similarly GCC haplotype correlated with positive PR expression and ATA and ACC with negative PR expression. Conclusion: The data of this study showed that IL-10 promoter gene polymorphisms may not be considered as one of the risk factors for breast cancer in Iranian patients.
Original Article
Tahereh Mousavi; Nahid Asadi; Majid Tebyanian
Volume 2, Issue 3 , September 2005, Pages 166-171
Abstract
Background: The incidence of allergic and asthmatic diseases has been continuously increased in both industrial and developing countries. Extracts from various known allergens are used for the diagnostic and therapeutic purposes. Objective: To investigate the effects of an extract prepared from Chenopodium ...
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Background: The incidence of allergic and asthmatic diseases has been continuously increased in both industrial and developing countries. Extracts from various known allergens are used for the diagnostic and therapeutic purposes. Objective: To investigate the effects of an extract prepared from Chenopodium album (Ch.A.) pollen to induce allergic asthma in BALB/C mice. Methods: BALB/C mice were sensitized by i.p. injection of Ch.A. extract and alum, and an intratracheal instillation of the extract. The bronchoalveolar lavage (BAL) fluids were obtained by cannulating the trachea and lavaging the lungs and examined for eosinophilia. Splenocytes were incubated with Ch.A. extract and cell supernatants were examined for IL-4 and IL-5 by ELISA. Results: We demonstrated that Ch.A. extract treatment in mice increased serum levels of specific IgE and production of IL-4 and IL-5 from splenocytes. An airway eosinophilia was also demonstrated in mice. Conclusion: These results suggest that Ch.A. allergen extract is a potential agent in inducing characteristics of allergic asthma in a mouse model useful in investigational studies.
Original Article
Abbasali Pourazar; Mansoor Salehi; Aabollah Jafarzadeh; Mohammad Kazemi Arababadi; Farzad Oreizi; Keivan Shariatinezhad
Volume 2, Issue 3 , September 2005, Pages 172-176
Abstract
Background: The risk of infection by transfusion-transmitted viruses has been reduced remarkably. However, a zero-risk blood supply is still desirable. The screening for antibody to HBc (anti-HBc) has been shown as an alternative test for the detection of HBV infection. Objective: The main aim of this ...
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Background: The risk of infection by transfusion-transmitted viruses has been reduced remarkably. However, a zero-risk blood supply is still desirable. The screening for antibody to HBc (anti-HBc) has been shown as an alternative test for the detection of HBV infection. Objective: The main aim of this study was to evaluate HBV infection markers and the potential value of anti-HBc testing of blood donors to detect HBV infection. Methods: In this descriptive cross-sectional study, 545 blood samples were collected and tested for HbsAg using ELISA method. Then all HBsAg negative samples were tested for anti-HBc by the same method. To detect HBV infection, all HBsAg negative and anti-HBc positive samples were tested by PCR for HBV DNA. Results: All blood samples were HBsAg negative of which, 43 (8%) were anti-HBc positive. From those which were positive for anti-HBc, five samples were also positive for HBV DNA. Conclusion: Occult HBV infection is a clinical form of HBV infection in which HBsAg is not expressed by HBV and blood samples cannot be screened by ELISA method, therefore more sensitive techniques are needed. Our results demonstrate that a complementary test such as PCR, for detecting HBV DNA, is essential to ensure safety of blood samples.
Original Article
Gholamreza Hatam; Azra Shamseddin; Farhoud Nikouee
Volume 2, Issue 3 , September 2005, Pages 177-181
Abstract
Background: Toxoplasmosis is a parasitic disease caused by protozoan, Toxoplasma gondii. Infections of human are common and are usually asymptomatic. The infection may be serious if is transmitted to the fetus during pregnancy. Prophylactic measures, early detection of the infection and treatment can ...
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Background: Toxoplasmosis is a parasitic disease caused by protozoan, Toxoplasma gondii. Infections of human are common and are usually asymptomatic. The infection may be serious if is transmitted to the fetus during pregnancy. Prophylactic measures, early detection of the infection and treatment can avoid congenital toxoplasmosis and many long term effects. Objective: Seroepidemiological study in young girls is useful to determine the prevalence of infection and to design prevention policies for them after marriage and during their pregnancy. This study was carried out in the years 2000-2001 in the region of Fasa of Fars province in the South of Iran, as a descriptive, analytic and cross sectional study. Methods: Serum Samples of 947 students were collected from high school girls of Fasa and studied by enzyme linked immunosorbant assay (ELISA). The positive and negative controls were also used. Results: The seroprevalance rate of toxoplasmosis ranged from 1 to 21 Percent in different parts of Fasa and 10% in all groups. Some variables including age, nutritional habits and contact with domestic cats were studied. Conclusion: The seroprevalence of toxoplasmosis in girls of various high schools of Fasa is different and it may be related to the level of hygiene in different parts of Fasa. Water and food contamination with cat stool in regions with high contact with domestic cats can play an important role in infection rates. People of such areas should eat well-cooked meat to reduce infection.
