Spontaneous in vitro IgE synthesis: modifications induced by immunotherapy

In this study, we used an in vitro experimental model with peripheral mononuclear cells (PBMCs) capable of synthesizing IgE to study the possible parallelism between in vitro IgE synthesis and the findings obtained in vivo showing changes in serum IgE values during immunotherapy (IT).

Blood samples were extracted from 10 healthy subjects and 39 allergic patients for lymphocyte culture. Allergic patients were classified into five groups according to the time of IT. After incubation for 7 days at 37 degrees C, IgE values were assessed by means of a radioimmunoassay technique modified for low values. Likewise, total serum IgE was assessed. Spontaneous in vitro production of IgE in control individuals (G0) was significantly lower (p < 0.001) than the mean production in allergic patients (GA). When patients were grouped according to the time of IT, we observed that IgE values decreased during the course of IT.

The significant differences found between allergic patients and control individuals eventually disappeared from the third year of treatment. We found a statistically significant positive correlation (r = 0.575, p < 0.001) between total serum IgE values and in vitro IgE production in all subjects. We conclude that IT induces a series of variations in lymphocyte IgE production in vitro, which consists of a significant decrease in IgE production from the second year of IT compared with that of patients without IT. IgE production eventually reaches levels similar to those in healthy subjects.

The symptomatic recovery shown by all patients was associated with evident immunological changes, which confirms the clinical utility of this treatment in allergic diseases and the importance of its long-term effects.

CITATION  J Investig Allergol Clin Immunol. 1993 Jul-Aug;3(4):178-81