Sorour Shojaeian; Amir Hassan Zamani; Mahmood Jeddi-Tehrani; Forouzandeh Fereidooni; Ebrahim Torkabadi; Mohammad Mehdi Akhondi; Akram Sadat Tabatabaei-Panah; Abdolamir Allameh
Volume 6, Issue 4 , December 2009, , Pages 174-185
Abstract
Background: Monoclonal antibodies (mAbs) are essential tools for many molecular im-munology investigations, epitope mapping and molecular modelling, clinical laboratory di-agnostic tests and immunotherapy. Humoral immune response of immunized animals largely depends on the nature of antigen and the immunization ...
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Background: Monoclonal antibodies (mAbs) are essential tools for many molecular im-munology investigations, epitope mapping and molecular modelling, clinical laboratory di-agnostic tests and immunotherapy. Humoral immune response of immunized animals largely depends on the nature of antigen and the immunization technique. Polysaccharides and heavily-glycosylated proteins are very elusive targets incapable of mounting long-lasting, high affinity antibody responses. Carcinoma antigen 125 (CA 125), a well known tumor marker of ovarian cancer, is a mucin type antigen consisting of repetitive units of heavily glycosylated moieties which render production of mAbs very difficult. Objective: To evaluate the efficacy of heterologous antigen preparations as a way of mouse immuniza-tion in the production of anti-CA 125 mAb. Methods: Two different protocols of immuni-zation were used for priming of NMRI mice. In the first method, mice conventionally im-munized by three intraperitoneal injections of purified CA 125 and boosted by the antigen three days before fusion. In the second approach, mice were primed by three intraperitoneal injections of living CA 125 positive cells of OVCAR-3 cell line, and boosted by intrave-nous injection of the purified extracellular domain of CA 125. Production of mAb was per-formed by standard hybridoma technology and mAbs were characterized by different im-munoassays. Results: The first method failed to produce stable clones despite six time fu-sion. A total of ten stable clones, however, were produced in the second approach. Some of the clones were characterized and found to have excellent immunoreactivity when tested by ELISA assay, western blotting, intracellular and surface immunofluorescent staining of OVCAR-3 cell line and immunohistochemical staining of ovarian cancer tissues. Conclusion: Altogether the results of the present study clearly showed that heterologous antigen preparation is the method of choice for immunization when production of mono-clonal antibody against highly glycosylated poorly immunogenic antigens is concerned.
Saeed Zarei; Mahmood Jeddi-Tehrani; Mohammad Mehdi Akhondi; Hojjat Zeraati; Tahere Kheirkhah; Morteza Ghazanfari; Fazel Shokri
Volume 4, Issue 2 , June 2007, , Pages 101-109
Abstract
Background: Immunization against diphtheria, tetanus and pertussis has been applied in Iran since 1950. WHO suggests periodical evaluation of effectiveness of the triple diphtheria-tetanus-whole cell pertussis (DTwP) vaccine, worldwide. Objectives: To determine the immunogenicity of locally manufactured ...
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Background: Immunization against diphtheria, tetanus and pertussis has been applied in Iran since 1950. WHO suggests periodical evaluation of effectiveness of the triple diphtheria-tetanus-whole cell pertussis (DTwP) vaccine, worldwide. Objectives: To determine the immunogenicity of locally manufactured DTwP vaccine administered to preschool children in a number of health centers of Tehran in 2006. Methods: In this prospective study, 350 children aged 4-6 years were injected with DTwP vaccine manu-factured by Razi Institute of Iran. Blood samples were collected before and 2-4 weeks after the vaccination. The immunogenicity of the vaccine was assayed by measurement of specific antibodies using enzyme-linked immunosorbent assay (ELISA) technique. Results: Of the 337 children who were vaccinated, 99.4% and 100% had protective anti-diphtheria and anti-tetanus antibody titers, respectively. The vaccine response and seroconversion for pertussis was achieved in 70.3% of the subjects. The geometric mean titers (GMT) of the antibodies produced against diphtheria, tetanus and pertussis by DTwP vaccine were 7.76, 9.37 IU/ml and 30.20 EU/ml after booster vaccine dose, respectively. Conclusions: Comparison of the results obtained from this study with those of previous studies performed in other countries reveals that immunogenicity of diphtheria and tetanus components is similar to other vaccines, but the immunogenicity of pertussis vaccine was less efficient. The lower immunogenicity of DTwP against pertussis may be related to the bacterial strain used or the formulation protocol adopted for the vaccine preparation.