RT Journal Article SR Electronic T1 Localisation of CD10 to biliary canaliculi by immunoelectron microscopical examination. JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 654 OP 656 DO 10.1136/jcp.43.8.654 VO 43 IS 8 A1 Loke, S L A1 Leung, C Y A1 Chiu, K Y A1 Yau, W L A1 Cheung, K N A1 Ma, L YR 1990 UL http://jcp.bmj.com/content/43/8/654.abstract AB Common acute lymphoblastic leukaemia antigen (CALLA) was first characterised in lymphoid leukaemic cells. The antigen is present in different stages of lymphoid cell differentiation as well as in subsets of myeloid cells, and further studies have also shown its presence in non-lymphoid tissues. The recent cloning and sequencing of the gene permitted deduction of its amino acid sequence which is identical with the human membrane-associated enzyme, neutral endopeptidase. Strong immunostaining for CALLA was detected in the human liver with a canalicular pattern. Immunoelectron microscopy also confirmed that the antigen was localised only in the area of the bile canaliculi. Although the function of neutral endopeptidase in the canaliculi is unknown, this antigen may prove useful in the study of biliary function and diseases.