A 5-Year Open-Label Follow-up of a Randomized Double-Blind Placebo-Controlled Trial of Intralymphatic Immunotherapy for Birch and Grass Allergy Reveals Long-term Beneficial Effects

BACKGROUND

Intralymphatic immunotherapy (ILIT) is a novel, faster alternative to conventional allergen immunotherapy (AIT). Few previous studies have evaluated its long-term effects. The objective of the present study was to complete a 5-year follow-up of a randomized double-blind placebo-controlled trial of ILIT for a combination of birch and grass allergens.

METHODS

Fifty-eight patients with allergic rhinitis were treated with either placebo or a combination of ALK Alutard Birch and Grass 1000 SQ-U administered in 3 intralymphatic injections at 1-month intervals. A year after the vaccination, the symptoms induced by nasal provocation were significantly reduced. After 5-6 years, 20 out of 26 actively treated patients were followed up with a nasal provocation test (NPT) and seasonal registration of the combined symptom and medications score (CSMS), IgE and IgG4 levels in blood, and immunological markers in blood and lymph nodes and compared with 13 unvaccinated controls.

RESULTS

The reduction in the NPT response with ILIT at year 1 could not be convincingly reproduced at year 5. The new CSMS scores were markedly lower among the previously treated patients than among the control group. Furthermore, grass-specific IgG4 was increased, grass-specific IgE decreased, FcεR1 on basophils was reduced, and the fraction of memory T-cells in lymph nodes increased.

CONCLUSION

The combination of seasonal clinical data and immunological parameters supports the notion of a long-lasting effect of ILIT. These data support the concept of ILIT as a good alternative to traditional AIT in pollen-induced allergic rhinitis.

Correlations of nasal responses to leukotriene D4 and histamine nasal provocation with quality of life in allergic rhinitis

Background

The symptoms of allergic rhinitis (AR) greatly affect the quality of life (QoL) in the patients with AR. The correlations of nasal response to leukotriene D4 (LTD4) and histamine nasal provocation with health related QoL in AR are not clear.

Objective

To evaluate the correlations of nasal response to LTD4 and histamine nasal challenge with QoL in AR.

Methods

Patients randomly underwent LTD4 and histamine nasal challenge tests, completed the rhinoconjunctivitis quality of life questionnaire (RQoLQ), and rating the symptom severity score (total symptom score 4, TSS4) in the previous week. The correlations between nasal challenge tests induced nasal responses and QoL in RQoLQ were analyzed.

Results

A total of 25 eligible AR patients enrolled and finished both LTD4 and histamine nasal challenge and completed the questionnaire of RQoLQ. Histamine nasal challenge induced sneezing, increased nasal resistant were correlated with most of the dimensions (general, practical, nasal, eye problems, and quality of sleep, p < 0.05), while LTD4 nasal challenge induced sneeze, increased nasal resistant only correlated with nasal and ocular problems. On the contrary, the severity of the sneeze assessed by TSS4, was not correlated with QoL, while the severity of rhinorrhea, congestion, and nasal pruritus were correlated with nasal and practical problems, and nasal congestion was also correlated with ocular problems (r = 0.60, p = 0.01).

Conclusion

LTD4 and histamine nasal challenge induced nasal responses were correlated with different clinical symptoms severity and QoL, which can be used as a good diagnosis and evaluation methods for the management of AR.

Recombinant allergen-based provocation testing

Over the last 25 years, recombinant allergens from all important allergen sources have been cloned and are now available as recombinant proteins. These molecules can be produced in practically unlimited amounts without biological or batch-to-batch variability. It has been shown in provocation tests that recombinant allergens have similar clinical effects as their natural counterparts. With the help of these tools it is possible to reveal the precise reactivity profiles of patients and to uncover and differentiate cross-reactivity from genuine sensitization to an allergen source. Although it has been shown some time ago that it would be possible to replace crude allergen extracts with recombinant allergens for skin prick testing, and even though the use of allergen components can improve routine diagnosis, these tools are still not available for clinical routine applications. The use of provocation tests is a crucial step in the development of new, hypoallergenic vaccines for therapy of allergic disease. Here we describe important provocation methods (skin prick test, intradermal test, atopy patch test, nasal provocation, colonoscopic provocation test) and give an overview of the clinical provocation studies which have been performed with recombinant allergens so far.