Meredith Moore1, Mark Tucker, Tom Grier, James Quinn. 1. Department of Allergy/Immunology (Wilford Hall Medical Center), San Antonio Uniformed Services Health Education Consortium, Lackland AFB, Texas 78236, USA. meredith.moore@us.af.mil
Abstract
BACKGROUND: Allergen extracts can degrade when exposed to temperatures significantly beyond the optimum storage recommendation of 4 degrees C. Many allergen extracts are mailed to their final destinations throughout the year with exposure to varied environmental conditions. OBJECTIVE: To evaluate the effect of summer mailing on the in vitro and in vivo potency of timothy grass extract. METHODS: Standardized timothy grass extracts, 10,000 and 100,000 BAU/mL, were mailed round-trip between San Antonio, Texas, and Phoenix, Arizona, during August 2007. In-transit temperatures were recorded using a portable temperature logger. After mailing of the extracts, we performed quantitative in vitro enzyme-linked immunosorbent assay inhibition and in vivo ID50 EAL (Intradermal Dilution for 50-mm Sum of Erythema Determines Bioequivalent Allergy Units) analysis. RESULTS: Measured extract exposure temperatures were greater than 20 degrees C for 11 days and 30 degrees C for 6 hours during standard mailing in weather temperatures exceeding 38 degrees C. Enzyme-linked immunosorbent assay inhibition results for the 100,000- and 10,000-BAU/mL control samples were 97,900 and 10,580 BAU/mL, respectively, and for the mailed extracts were 96,800 and 7830 BAU/mL, respectively. These measurements fell within the current Food and Drug Administration lot release limits (67%-149%) and stability limits (50%-200%) relative to the standardized reference. The ID50EAL determinations of the control vs mailed extracts were 12.98 vs. 12.28, 12.66 vs. 12.32, and 11.97 vs 11.70 for the 3 patients. These differences were not statistically significant. CONCLUSIONS: Mailing of timothy grass extract produced no significant reductions in in vitro relative potencies or in vivo skin test reactivity in 3 sensitive patients.
BACKGROUND: Allergen extracts can degrade when exposed to temperatures significantly beyond the optimum storage recommendation of 4 degrees C. Many allergen extracts are mailed to their final destinations throughout the year with exposure to varied environmental conditions. OBJECTIVE: To evaluate the effect of summer mailing on the in vitro and in vivo potency of timothy grass extract. METHODS: Standardized timothy grass extracts, 10,000 and 100,000 BAU/mL, were mailed round-trip between San Antonio, Texas, and Phoenix, Arizona, during August 2007. In-transit temperatures were recorded using a portable temperature logger. After mailing of the extracts, we performed quantitative in vitro enzyme-linked immunosorbent assay inhibition and in vivo ID50 EAL (Intradermal Dilution for 50-mm Sum of Erythema Determines Bioequivalent Allergy Units) analysis. RESULTS: Measured extract exposure temperatures were greater than 20 degrees C for 11 days and 30 degrees C for 6 hours during standard mailing in weather temperatures exceeding 38 degrees C. Enzyme-linked immunosorbent assay inhibition results for the 100,000- and 10,000-BAU/mL control samples were 97,900 and 10,580 BAU/mL, respectively, and for the mailed extracts were 96,800 and 7830 BAU/mL, respectively. These measurements fell within the current Food and Drug Administration lot release limits (67%-149%) and stability limits (50%-200%) relative to the standardized reference. The ID50EAL determinations of the control vs mailed extracts were 12.98 vs. 12.28, 12.66 vs. 12.32, and 11.97 vs 11.70 for the 3 patients. These differences were not statistically significant. CONCLUSIONS: Mailing of timothy grass extract produced no significant reductions in in vitro relative potencies or in vivo skin test reactivity in 3 sensitive patients.