Two-color flow cytometric analysis of the expression of MAC and MHC class II antigens on macrophages during tumor growth.
Tumor-bearing host (TBH) macrophages (M phi) exhibit immune dysfunction that is concomitant with phenotypic changes. We examined M phi subpopulations by changes in the expression of surface antigens Mac-1, -2, -3, and Ia on normal and TBH peritoneal and splenic M phi. M phi were double-labeled and analyzed by flow cytometry to observe multiple expression of surface antigens. Tumor growth alters the multiple expression of these M phi markers. Peritoneal and splenic M phi had different Mac+ and Mac+Ia+ population percentages. In TBH, peritoneal M phi had decreased percentages of Mac-1+2+, Mac-1+3+, Mac-2+3+, and Mac+Ia+ M phi. This decrease correlated with functional changes in TBH M phi. In contrast, there was an increase in Mac-2-Ia- TBH peritoneal M phi. Previously undiscovered Mac-1+2-3- and Mac-1-2-3+ populations were found. In contrast to peritoneal M phi, there was an increase in the percentage of Mac-1+2+, Mac-1+3+, and Mac-2+3+ splenic TBH M phi but, like peritoneal M phi, there was a decrease in the percentage of Mac+Ia+ M phi. Also, TBH splenic M phi showed a smaller but more uniform antigen density than normal host splenic M phi. Tumor growth modulated phenotypic alterations in peritoneal and splenic M phi subpopulations. Combined with earlier functional studies of M phi subpopulations, these data suggested a relationship between changes in M phi phenotype and tumor-induced dysfunction of M phi-modulated immune activity.
Department of Biology, Virginia Polytechnic Institute and State University, Blacksburg 24061.
A D
AD
Yurochko
C J
CJ
Burger
K D
KD
Elgert
D000818:Animals; D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation / Q000096:biosynthesis*; D000954:Antigens, Surface / Q000096:biosynthesis*; D005354:Fibrosarcoma / Q000276:immunology*; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis*; D016177:Macrophage-1 Antigen; D008264:Macrophages / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010529:Peritoneal Cavity / Q000166:cytology; D010641:Phenotype; D016028:Receptors, Leukocyte-Adhesion / Q000096:biosynthesis*; D013154:Spleen / Q000166:cytology
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000954:Antigens, Surface; D000949:Histocompatibility Antigens Class II; D016177:Macrophage-1 Antigen; D016028:Receptors, Leukocyte-Adhesion