Figure 4.

HLA-I expression patterns in biphasic and poorly differentiated SS.

Antibody staining specific for HLA-A and HLA-B/C on tumour sections of biphasic SS (a-e) and poorly differentiated SS (f). a) Absent staining of HLA-A on SS46. b) Low, focal expression of HLA-A on SS15. c-e) Heterogeneous expression of HLA-A on SS34 (c) and HLA-B/C on SS23 (d) and SS24 (e) with the biphasic component of the tumour demonstrating clear up regulation of HLA-I compared to the spindle cell compartment that lies in between the biphasic parts. Note that HLA-I is elevated on the epithelial-like ducts in SS24 (e). f) SS50, demonstrating heterogeneous expression of HLA-A on a poorly differentiated SS.Scale bars a-c, e-f: 50 µm; d: 100 µm.