KROK 1 2007 – Question 76 · KROK (Medicine) · Microbiology, Virology, and Immunology
In order to estimate toxigenity of diphtheria agents obtained from patients the cultures were inoculated on Petri dish with nutrient agar on either side of a filter paper strip that was put into the centre and moistened with antidiphtheric antitoxic serum. After incubation of inoculations in agar the strip-like areas of medium turbidity were found between separate cultures and the strip of filter paper. What immunological reaction was conducted?
- A. Coomb’s test
- B. Rings precipitation reaction
- C. Opsonization reaction
- D. Agglutination reaction
- E. Precipitation gel reaction
Hint
Think about what forms when a soluble toxin diffusing from the colonies meets antibody diffusing from the paper strip, in the proper proportion, inside a semisolid medium.
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