en Immunology Immunology Original Research: Basic Science in Medicine Original Research: Basic Science in Medicine Serum opsonic capacity against B. pertussis was studied by using quantitative chemiluminescence (CL), a method known to have several advantages over conventional methods in evaluating opsonization and phagocytosis. Sera from unvaccinated infants was shown not to contain opsonins against B. pertussis and in unvaccinated infants suffering from whooping cough, no opsonins were detected. In adults fully vaccinated during childhood, antibody titers decreased with time. Therefore, antibody transfer to infants is negligible. The CL assay is simple, rapid, and reproducible, offering new possibilities to evaluate humoral immune mechanisms and phagocytosis in whooping cough. 65 67 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-465&slc_lang=en&sid=1 A A. ISAIAN 20031947532846005464 20031947532846005464 Yes From the Department of Immunology and Allergy, Tehran University of Medical Sciences, Tehran, Islamic Republic of Iran. A FARHOUDI 20031947532846005465 20031947532846005465 No