Decrease of activated lymphocytes four and nine hours after a subcutaneous injection of a Viscum album L. extract in healthy volunteers.

The immunomodulatory substance, VaQuFrF (an aqueous extract of Viscum album L. of the oak tree) is used as an adjuvant and as monotherapy in the treatment of cancer and AIDS. After subcutaneous injection, there is a local inflammatory reaction at the injection site and systemic elevation of activated lymphocytes. The immunomodulatory effect of VaQuFrF in the first 24 h after subcutaneous injection on blood leukocyte and lymphocyte subpopulation was investigated. Because a significant natural circadian variation of these cellular parameters exist, the influence was studied in regard to this. In two groups of healthy volunteers, one group receiving VaQuFrF, the following parameters were measured every 2-3 h over a period of 24 h: leukocytes, band form, segmented and eosinophilic granulocytes, monocytes, total lymphocytes and CD4-, CD8-, CD3/25- and CD8/38-positive lymphocytes in count and percentage. In regard to the natural circadian variation 24 h after injection of VaQuFrF, a statistically significant fall in the absolute numbers and percentage of CD3/ 25- and CD8/38-positive lymphocytes was observed. Also, monocytes in percent and absolute numbers show a transient fall 6-9 h, lymphocytes only in absolute and CD4-positive lymphocytes only in percentage 2 h after injection. The results demonstrate that there is increased extravasation of (activated) lymphocytes and monocytes after subcutaneous injection of 1 mg VaQuFrF.