Epidemiologic evidence links Th2 cytokine responses to the pathogenesis of atopy/asthma. It is hypothesized that certain immunizations may induce/amplify Th2 cytokine responses. The objective of this study was to determine whether Th cytokine responses to immunization with tetanus toxoid differ in AR and non-AR adults.

Thirty subjects were enrolled (15 with allergic rhinitis and 15 without allergic rhinitis as confirmed by history and allergy skin testing). Blood was collected before (day 0) and on days 3, 7, 14 and 28 following immunization with tetanus toxoid. PMNCs were purified and cultured with either PHA or tetanus toxoid for 2 or 6 days, respectively. Supernatants were harvested and assayed for IFN-γ and IL-13 levels by EIA. Results were normalized by log transformation and analyzed by step-wise regression.

Baseline (day 0) cytokine values were similar in both groups. PHA and tetanus-induced IFN-γ were increased (p<0.05) in non-AR (3.2 ± 0.3 and 1.4 ± 0.3 on day 7, and 3.5 ± 0.2 and 1.9 ± 0.2 on day 14, respectively) as compared to AR subjects (2.3 ± 0.3 and 0.9 ± 0.3 on day 14, and 2.7 ± 0.3 and1.2 ± 0.3 on day 14, respectively). PHA-induced, but not tetanus-induced, IL-13 production was increased (p<0.05) in non-AR as compared to AR subjects on day 7 (p<0.05). PHA-induced IL-13 production was 3.1 ± 0.2 in non-AR and 2.6 ± 0.3 in AR subjects on day 7.

These results demonstrate differential Th cytokine responses in AR and non-AR subjects following immunization with tetanus toxoid. Future studies in this area are warranted and may result in the identification of potential prevention/treatment strategies for atopy/asthma.