Effects of immunostimulants in phototherapy for cancer treatment

It has long been established that exogenous immunostimulants can enhance the host defense system. The use of such immunoadjuvants in most cases has often been proven non-specific, hence limiting their capability in fighting against specific foreign invasion, particularly against tumor cells, which in most cases can easily evade the host immune surveillance system. However, when the non-specific immunological enhancement is combined with other direct intervention, the immune responses could be turned to be tumor-specific. Glycated chitosan (GC), a specially designed immunoadjuvant, has been used in combination with phototherapy for cancer treatment with promising outcomes in animal studies. Here we present our results of cellular studies on the functions of GC. When used by itself, GC was not toxic to normal cells as well as to tumor cells. When GC was incubated with macrophages, it could induce significant secretion of TNFα. Furthermore, when GC was used with laser irradiation, it has significantly enhanced tumor cell destruction and immune responses.