T cell responses to the purified major allergens from the house dust mite Dermatophagoides pteronyssinus.

Proliferation assays were used to determine peripheral blood T cell responses to affinity-purified Der p I, Der p II, and Der f II allergens. Patients studied were sensitive to the house dust mite (HDM) either alone or in combination with other allergens. Control subjects were both nonatopic and atopic non-HDM sensitive. In general, only HDM-sensitive patients responded to the mite allergens. Mean stimulation indices (SI) were 10.2 +/- 2.8 (SEM) for Der p I and 10.0 +/- 2.2 for Der p II in HDM-sensitive individuals, and 2.0 +/- 0.2 and 2.8 +/- 0.6 for non-HDM sensitive control subjects (p less than 0.001). Patients sensitive to HDM and other allergens had higher responses than subjects sensitive to HDM alone, and the degree of proliferation to Der p I and Der p II was well correlated in individual patients (r = 0.71; p less than 0.001). Total IgE levels were elevated in the allergic patients, and values were highly correlated with the SI for both Der p I and Der p II (p less than 0.001). Responses to Der p II and Der f II were equivalent in 82% of individuals; however, in 18%, there was a marked discordance with strong responses to Der p II only. SIs were compared between different clinical groups of patients, and patients with asthma had significantly higher values to both Der p I and Der p II than patients with rhinitis alone (17.0 +/- 5.4 versus 5.7 +/- 1.0 for Der p I, p less than 0.05; 14.3 +/- 6.8 versus 5.0 +/- 1.0 for Der p II, p less than 0.05).