Proteinase Activity of Rat Lymph Nodes †

Proteolytic activity in extracts of lymphatic tissue has been described in the older literature,11 gelatin, casein, and serum albumin having been used as substrates. More recently bovine tonsils were reported to contain a protease that cleaves serum albumin.7 Rothschild and Junqueirae found proteolytic activity in lymph node homogenates, using globin as substrate. In the present investigation, an attempt was made to characterize the proteolytic activity of rat lymph nodes by using both synthetic and protein substrates, and to relate the proteolytic activity of this tissue to that previously described for enzymes derived from bovine spleen."'8