ABSTRACT
Low molecular weight factors, derived from head and neck carcinomas (H/N ca LMWFs), exert a serious inhibitory effect on monocyte chemotaxis both in vivo and in vitro. This effect can be neutralized by the treatment of the factors with three different monoclonal antibodies to P15E, one of the structural envelope proteins of murine leukemia virus (MuLV). In this study, we report the effect of the H/N ca LMWFs on the delayed type hypersensitivity responsiveness in mice: the factors significantly inhibited the 24 hour DNFB skin reaction. These effects of the H/N ca LMWFs were again neutralizable by antibodies to P15E. Additional experiments showed that the H/N ca LMWFs had equal suppressive effects on toxic skin reactions to croton oil, and this indicates that the P15E-like H/N ca LMWFs exert their effect by aspecific mechanisms.
Subject(s)
Carcinoma, Squamous Cell/immunology , Head and Neck Neoplasms/analysis , Hypersensitivity, Delayed/immunology , Neoplasm Proteins/immunology , Aged , Animals , Female , Humans , Male , Mice , Mice, Inbred C3H , Middle Aged , Neoplasm Proteins/analysis , Retroviridae Proteins/immunologyABSTRACT
We report on the effect of low molecular weight factors (LMWFs) derived from 14 different head and neck carcinomas on the chemotactic responsiveness of healthy donor monocytes, as measured by their polarization activity. The factors inhibited the polarization of the monocytes significantly (61.5% to 94.5% vs 12.5% to 29% in cases where the LMWF was derived from healthy oral mucosa). The inhibitory effect exerted by these LMWFs could be neutralized only by absorption with one of three different murine monoclonal antibodies or a rabbit polyclonal antibody to the murine retroviral envelope protein P15E. This shows that retroviral-related material is present in head and neck carcinomas and that this material is responsible for the observed defective polarization that probably underlies the earlier described defects on monocyte chemotactic responsiveness.
