sepharose and Mast-Cell-Sarcoma

The effects of macrophage adherence to plastic on tumoricidal activity were investigated. In order to do so, an agarose culture system was developed to provide a means for maintaining non-adherent macrophages in vitro. We were not able to show any effects of adherence on tumour cell lysis by activated macrophages. On the other hand, in vitro activation of non-adherent macrophages was possible only if adherence was replaced by another triggering signal. This requirement was more significant in the A/J mouse strain, where non-adherent macrophages required longer activation periods. Hence we propose that adherence might provide a second signal for the in vitro induction of tumour killing. The biological significance of adherence that is relevant to tumour killing is discussed.

Topics: Animals; Cell Adhesion; Cells, Cultured; Cytotoxicity, Immunologic; Female; Macrophage Activation; Macrophages; Male; Mast-Cell Sarcoma; Mice; Mice, Inbred A; Mice, Inbred C3H; Sepharose; Tumor Cells, Cultured

Histidine decarboxylase (EC 4.1.1.22) from a mouse mastocytoma has been purified by chromatography on charged and non-charged n-alkyl derivatives of agarose. The former was represented by the coupling product of CNBr-activated agarose and alkylmonoamines (alkylamino-agarose), the latter by the coupling of agarose and alkylglycidyl ehters (alkyl agarose). The choice of fractionation medium was restricted by the enzyme stability; excessively high ionic strength media could not be used. Under the conditions investigated, the best result was obtained with the non-charged ocytl agarose. The enzyme was adsorbed to this gel at a relatively high ionic strength, and on stepwise decrease in ionic stength of the eluting buffer it was desorbed with a total recovery of 80%. There was an approx. 10-fold increase in specific activity. The histidine decarboxylase, thus purified, retained 90-100% of its activity for 10 days or more at 6-8 degrees C. Some general comments on protein fractionation on charged and non-charged alkyl derivatives of agarose are given. The complexity of protein interaction with the charged alkyl derivatives is illustrated by experiments with a colored protein, phycoerythrin.

Topics: Animals; Carboxy-Lyases; Chromatography, Affinity; Histidine Decarboxylase; Mast-Cell Sarcoma; Mice; Neoplasms, Experimental; Sepharose