To investigate the mechanisms responsible for the late-phase response in patients with
allergies, we measured four biochemical mediators (
histamine, tosyl-
L-arginine methyl ester [
TAME]-esterase,
kinin, and
prostaglandin D2) in nasal secretions after nasal challenge with pollen
antigen in 12 patients with
allergy. Nine patients had an immediate response and a recurrence of symptoms 3 to 11 hours after challenge. The clinical symptoms during recurrence were accompanied by a second increase in levels of
histamine,
TAME--esterase, and
kinin over base-line values, although
kinin levels were lower than during the immediate response. In contrast, although the levels of
prostaglandin D2 were significantly increased during the immediate response, they did not increase above base line during the late response. Rechallenge with
allergen 11 hours after the initial provocation, however, was associated with reappearance of all four biochemical mediators, including
prostaglandin D2. We conclude that the late response to nasal challenge with
allergen is accompanied by a second increase in the concentrations of
histamine and
TAME--esterase but differs from the immediate response in the lack of
prostaglandin D2 production and in the amount of
kinin generated. Since
histamine is released only by mast cells and basophils and
prostaglandin D2 is not produced by basophils, we suggest that these cells are partly responsible for the late-phase response.