Lymphocyte subsets in tumour patients during subcutaneous mistletoe therapy

Objective: In order to exclude the possibility that mistletoe therapy may r esult in immunosuppression, as indicated by a significant reduction of defi ned lymphocyte subsets, Patients and Methods: peripheral blood cells of 23 tumour patients were treated subcutaneously with increasing concentrations of aqueous mistletoe extracts (Helixor(R)). Results and Conclusions: Within an observation period of 7 months, the relative amount of lymphocytes and the number of natural killer (NK) cells increased while the number of lymph ocyte subsets (i.e. CD19+ B cells, CD4+ T helper cells, CD8+ CD28- suppress or cells, CD8+ CD28+ cytotoxic cells) and the proportion of CD25+ (activate d) cells within T cells showed a statistically remarkable trend; due to the multiple test problem of statistical evaluation this trend is not allowed to be termed significant The leucocytes decreased insignificantly within th e observation period. However, we were unable to verify a suggested increas e of defined lymphocyte subsets within 23 months after the onset of mistlet oe treatment. Nevertheless, for the parameters CD19+ B cells, CD4+ T helper cells, CD8+ cells, CD8+ CD28+ cytotoxic cells and CD16+/CD56+ NK cells we observed statistically remarkable peaks within die 2nd and 3rd month of the rapy, confirming the hypothesis. The responses to the extracts were obvious ly interindividually different; the immune responses especially of patients with a lower number of peripheral T cells were less significant as compare d to those of patients with adequate T cell numbers. Surprisingly, even an increase of the drug concentration >3 ng mistletoe lectin (as determined wi thin the whole plant extract) per kg body weight enhanced the number of CD4 + T helper cells. A decreased immunological reaction on mistletoe extracts was shown especially for patients with a reduced number of peripheral T cel ls, whereas patients with normal T-cell number were more reactive.