Abstract:
Eosinophilic leukocytes and mistletoe-lectin specific anti-ML-1-IgG subclasses were monitored in breast cancer patients during 24 months of treatment with a mistletoe extract (ABNOBAviscum Mali (R)) in an ambulatory oncologic setting and evaluated retrospectively. The aim is to provide a pool of data on these parameters and perform an explorative analysis.
During 24 months of treatment, all patients developed IgG antibodies against mistletoe lectin I (ML-1). The individual patterns of IgG-subclass distribution were highly variable and did not correlate with other parameters. The production of IgG1 and IgG3 began earlier than that of IgG4. IgG2 reached a maximum prevalence of only 18% and declined later. In a logarithmic model, the titer of IgG1and IgG4 increased significantly between the month 3 and month 24.
A significant positive correlation was found for the non-logarithmic mean of IgG1 with IgG4, IgG2 with IgG4 and IgG2 with IgG3 (p< 0,01). No significant correlation of IgG-subclass levels existed with eosinophils. The eosinophils themselves where significantly elevated in month 1 and month 24. Despite of a high immunogenic potential of the used mistletoe extract, no severe adverse reactions were observed. This study underlines the earlier described high potency of mistletoe extracts to induce anti-ML1-IgG and elevations in eosinophilic counts. Given the fact that the eosinophily occurs much earlier in the treatment course than the subsequent conversion for IgG2 and IgG4 antibodies, it is assumed that eosinophily is triggered by mechanisms of the unspecific immune system in response to mistletoe components. When using the IgG-subclass distribution to estimate the polarisation of the immune response to mistletoe, a co-stimulation of both Typ-1- and Typ-2- paths is observed within 24 months of treatment with mistletoe extracts. Further studies are needed to examine the significance of eosinophily and anti-ML1-IgG production during treatment with mistletoe extracts.