1. ¹Department of Surgery, University of Adelaide, Royal Adelaide Hospital, North Terrace, Adelaide, South Australia 5000, Australia
2. ²Haematology/Immunology Research Group, University of Otago, Canterbury Health Laboratories, PO Box 151, Christchurch, New Zealand
3. ³Mater Medical Research Institute, Mater Hospital, Brisbane, Queensland 4101, Australia

Correspondence: Dr BJ Coventry, E-mail: brendon.coventry@adelaide.edu.au

Received 19 November 2001; Accepted 4 December 2001.

Abstract

Low CD1a-positive putative dendritic cell numbers in human breast cancer has recently been described and may explain the apparent 'poor immunogenicity' previously reported in breast cancer. Little attention has been given to dendritic cell activation within the tumour microenvironment, which is another reason why the in-situ immune response may be severely deficient. We have therefore examined CD1a expression as a marker for dendritic cells, together with CMRF-44 and -56 as markers of dendritic cell activation status, in 40 human breast cancers. The results demonstrate few or no CD1a-positive putative dendritic cells and minimal or no expression of the dendritic cell activation markers. Both dendritic cell number and dendritic cell activation appear substantially deficient in human breast cancers, regardless of tumour histological grade.