Sensitization of Guinea Pigs to Cotton Linters and House Dust Extracts

Abstract

Since Cooke 1 first directed attention to the importance of house dust as a specific excitant of asthma, there have been many attempts to characterize a hypothetical dust allergen. Its existence, as an entity, was recently questioned by Walzer 2 on the basis of critical examination of available clinical data pertaining to dust sensitiveness. He found among these data evidence of reactions which he attributed to non-specific irritative principles in extracts of house dust or other dusty substances. Noted also was the fact that no one had succeeded in sensitizing experimental animals to house dust 3 nor to suspected parent substances, cotton linters, 4 kapok fiber dust, 5 or mold 6 (Aspergillus fumigatus).

Adaptation of the alum precipitation technic devised by Harrison 7 and employed by Caulfeild, Brown and Waters 8 in sensitizing guinea pigs to ragweed pollen extracts, has proved effective for establishing anaphylactic sensitiveness to water extracts of linters and house dust, respectively. Comparing anaphylactogenic properties of these extracts led to recognition of a non-specific factor in house dust extracts which induced anaphylactoid symptoms in unsensitized guinea pigs.

Two samples of clean, unused cotton linters were extracted with distilled water saturated with toluene. A 100 g sample was divided into 5 equal portions. To one 20 g portion sufficient solvent (100 ml) was added to saturate the fibers. After agitating for 48 hours, in a jar fixed on a rocking platform, the mixture was transferred to a Buchner funnel. The solution, recovered by suction and mechanical pressure, was made up to 100 ml with water and used in the same manner to extract in succession the 4 remaining portions of the sample.