T Lymphocytes in Histiocytic Sarcomas of Flat-Coated Retriever Dogs.
Flat-Coated Retriever dogs are predisposed to the development of histiocytic sarcoma (HS), a poorly differentiated, highly malignant neoplasm. The authors have previously documented a significant lymphocytic infiltrate in such tumors. The objective of this study was to examine the presence and expression of regulatory T cells in HS tumor samples. Forty tumors were included in this study. All tumors were immunolabeled for CD3, CD79a, CD25, CD45RA, and FOXP3. The proportion of positive cells was compared between tumors presenting as a localized primary soft tissue mass (soft tissue origin HS) and disseminated HS affecting viscera, especially the spleen (splenic origin HS). By immunohistochemistry, 95% of infiltrating T cells were positive for Foxp3 in all sections, suggesting the presence of regulatory T cells. The proportion of cells positive for FOXP3 was higher in the tumors arising in soft tissues, whereas the proportion of CD45RA-positive cells was higher in the splenic origin HS. Canine HS has an aggressive clinical behavior and is uniformly fatal. The difference in the proportion of tumor-infiltrating lymphocytes positive for these 2 markers in the 2 locations may represent differences in tumor microenvironment between the 2 sites.
['Marcinowska|A|A|', 'Constantino-Casas|F|F|', 'Williams|T|T|', 'Hoather|T|T|', 'Blacklaws|B|B|', 'Dobson|J|J|']
D000818:Animals D017252:CD3 Complex D051925:CD79 Antigens D004283:Dog Diseases D004285:Dogs D005260:Female D051858:Forkhead Transcription Factors D054747:Histiocytic Sarcoma D053645:Interleukin-2 Receptor alpha Subunit D017493:Leukocyte Common Antigens D008297:Male D050378:T-Lymphocytes, Regulatory D059016:Tumor Microenvironment
histiocytic sarcoma Flat-Coated Retriever regulatory T cells tumor-infiltrating lymphocytes tumor microenvironment cancer immunology hematologic neoplasms