Restoration of E-rosette formation by levamisole and its abrogation by autochthonous serum from cattle with squamous cell carcinoma of horn.

The effect of levamisole on the erythrocyte rosette (E-rosette) forming capacity of peripheral blood lymphocytes from eight horn cancer affected and an equal number of unaffected control animals was studied in vitro. There was an appreciable increase (from 38.75 +/- 2.91 to 56.90 +/- 2.37) in the number of E-rosette forming cells when peripheral blood lymphocytes from horn cancer affected animals were treated with levamisole. However, no significant variation in E-rosette values was noticed when peripheral blood lymphocytes from control animals were treated with this drug. This restorative effect of levamisole on E-rosetting capacity of peripheral blood lymphocytes was abrogated (mean value 39.50 +/- 3.07) when peripheral blood lymphocytes were first treated with levamisole and then incubated in the presence of 50 per cent autochthonous horn cancer serum.