Host-tumor relationship XXXIII. Inhibitor of hyaluronidase in blood serum of cancer patients.

Inhibiting activity of blood serum was determined from the decrease of N-acetyl-hexosamine end groups of hyaluronic acid products released by testicular hyaluronidase. Maximum inhibition was observed within the region of pH from 6.5 to 6.8. Correlation between the serum concentration and its inhibiting effect on hyaluronidase was found within the range of the final dilution of serum (in the reaction mixture) from 9 to 45 X. Blood sera of cancer patients showed statistically significant increase of hyaluronidase inhibitor as compared with that of health people.