Abstract
OK-432, one of the so-called biological response modifiers (BRMs), has been reported to restore cellular and humoral immune responses in tumor-bearing individuals. However, since host immune responses in tumor-bearing individuals are modified by development of disease, by application of various forms of anticancer therapy, surgical operation, and by radiation therapy, it is sometimes impossible to evaluate accurately the effect of these nonspecific BRM restoring impaired immune response in patients with malignancy. Avoiding this problem, we studied the effect of BRM on host immune responses in the aged individuals without malignancy, who had shown decreased cellular immunity detected by PPD and PHA skin tests and in vitro blastoid transformation test of lymphocytes by PHA. Although OK-432 is used widely by intradermal or intramuscular injections, it is more convenient for the patients to receive oral administration than intramuscular injection having the side effects such as chill and fever.
Five KE or 20 KE of OK-432 was orally given three times a week for 1 month to the aged patients without malignancy who showed decreased skin responses to PPD and PHA. Oral adminstration of 5 KE of OK-432 evoked an increased skin response to PPD except 2 patients. PPD skin response was much more increased by the oral administration of 20 KE of OK-432, and the increased responsiveness was detected even 2 months after withdrawal of OK-432. There was same tendency in the skin response to PHA. The increased skin reaction to SuPS (lipopolysaccharide fraction of Streptococcus pyogenes Su strain) was observed in the one group of patients treated with 5 KE of OK-432, while there was no significant increased response by oral administration of 20 KE of OK-432.
It was concluded that the activation of non-specific host immune responses assessed by the skin tests used by us could be evoked by the oral administration of OK-432 as well as intramuscular injection.
