Y. Ohashi et al., SEASONAL RISE IN INTERLEUKIN-4 DURING POLLEN SEASON IS RELATED TO SEASONAL RISE IN SPECIFIC IGE FOR POLLENS BUT MOT FOR MITES, Acta oto-laryngologica, 118(2), 1998, pp. 243-247
Since IL-4 plays a key role in inducing and increasing the generation
of not only primary polyclonal but also secondary specific IgE respons
es by B lymphocytes, a seasonal increase in IL-4 is likely to be invol
ved in such seasonal rises in specific IgE in seasonal allergic rhinit
is. The first aim of this study was to investigate the possible season
al increase in serum IL-4 in patients with seasonal allergic rhinitis
due to Japanese cedar pollens. If serum IL-4 increases in response to
seasonal pollen exposure and is responsible for the seasonal increase
in pollen-specific IgE in sera, this increase in IL-4 might theoretica
lly affect specific IEE synthesis for other allergens. The second aim
was to investigate the effect of natural pollen exposure on serum conc
entrations of house dust mite-specific IgE in patients who have season
al allergic rhinitis and concurrent perennial allergic rhinitis due to
house dust miles. This study included 55 adult patients with seasonal
and perennial allergic rhinitis due to Japanese cedar pollens and Der
matophagoides farinae (D. farinae). Venous blood was collected twice f
rom each patient, before and during the cedar pollen season 1996, to d
etermine IL-4, cedar pollen-specific IgE and D. farinae-specific IgE i
n sera. Both IL-4 and pollen-specific IgE in sera were significantly i
ncreased during the pollen season, and the seasonal increase rate in p
ollen-specific IgE was significantly correlated with the seasonal incr
ease rate in IL-4. By contrast, D. farinae-specific IgE was not change
d during the pollen season in these patients. In conclusion, an elevat
ion of IL-4 in sera during the pollen season may play an important par
t in the seasonal rise in pollen-specfic IgE, and enhancement of speci
fic IgE synthesis is likely to need not only an increase in IL-4 but a
lso an increase in the number and/or capacity of specific IgE-secretin
g B cells.