Changes in the levels of house dust mite specific IgG4 during immunotherapy in asthmatic children


Lai-Chen Tsai, Department of Medical Research, Veterans General Hospital, Taipei, Taiwan, R.O.C.


Serum levels of IgG subclass and house dust mite (Dermatophagoides pteronyssinus, Dpt) specific IgG4 were evaluated during immunotherapy in asthmatic children. Asthmatic children undergoing long-term immunotherapy (more than 2 years) posed a mean value of total serum IgG4 or Dpt-specific IgG4 antibodies significantly higher than that of patients prior to receiving immunotherapy, asthmatic (placebo) controls, or patients undergoing short-term immunotherapy (less than 1 year) (P < 0.05). The mean levels of serum Dpt-specific IgG4 in all asthmatic groups were also significantly higher than in the non-allergic controls (P < 0.01). Moreover, the mean level of Dpt-specific IgG4 tended to increase during immunotherapy. A significant correlation between total serum IgG4 and Dpt-specirk IgG4 antibodies was noted (r= 0.6243; P < 0.001). Serial follow-up reveals that Dpt-specific IgG4 levels usually rose significantly with clinical improvement in asthmatic children during immunoiherapy. These results suggest that the anti-mite-specific IgG4 antibody may serve as an indicator for clinical outcome of mite allergy during immunotherapy.