Evaluation of RAST inhibition as a method for standardization of ragweed pollen extracts.

The RAST inhibition technique was evaluated as a method for standardization of ragweed pollen extracts. Seven different ragweed extracts were examined. There was no relationship between the RAST inhibition results and the commonly used parameters of extract potency including weight/volume, PNU and total protein measurements. Intradermal skin test end point titration was variable in different patients and could not correlated with RAST inhibition results. However, RAST inhibition potency did correlate with the antigen E content of the extract and this finding suggests that RAST inhibition might provide a method for better standardization of allergen extracts.