Characterization of inflammatory infiltrates in chronic chagasic myocardial lesions: presence of tumor necrosis factor-alpha+ cells and dominance of granzyme A+, CD8+ lymphocytes.
The inflammatory infiltrates in the heart lesions of chronic chagasic cardiomyopathy are composed predominantly of small lymphocytes with admixed macrophages, plasma cells, and segmented leukocytes. The phenotypes of the lymphoid cells in these infiltrates of human Chagas' disease have not been previously detailed. We used a panel of monoclonal and polyclonal antibodies to immunohistochemically characterize the inflammatory cells in frozen and fixed cardiac tissues from autopsied patients with severe chronic chagasic cardiomyopathy. In all cases, the inflammatory lesions were dominated by CD8+ lymphocytes, many of which expressed granzyme A. A few macrophage-like cells that expressed tumor necrosis factor-alpha were observed in each case. Relatively few natural killer cells or B lymphocytes were found in the lesions. These findings in human chagasic lesions are compatible with concepts that involve cytolysis and fibrosis, and new experimental findings that emphasize potential roles for CD8+ T cells in Chagas' disease.
Departamento de Bioquimica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
D D
DD
Reis
E M
EM
Jones
S
S
Tostes
E R
ER
Lopes
G
G
Gazzinelli
D G
DG
Colley
T L
TL
McCurley
D001402:B-Lymphocytes / Q000473:pathology; D015704:CD4 Antigens / Q000032:analysis; D016516:CD4-CD8 Ratio; D016827:CD8 Antigens / Q000032:analysis*; D002598:Chagas Cardiomyopathy / Q000473:pathology*; D002908:Chronic Disease; D005355:Fibrosis; D005629:Frozen Sections; D053804:Granzymes; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D008264:Macrophages / Q000473:pathology; D009206:Myocardium / Q000473:pathology*; D016612:Paraffin Embedding; D012697:Serine Endopeptidases / Q000032:analysis*; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology; D013602:T-Lymphocytes, Cytotoxic / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*
D015704:CD4 Antigens; D016827:CD8 Antigens; D014409:Tumor Necrosis Factor-alpha; D053804:Granzymes; D012697:Serine Endopeptidases; C509212:GZMA protein, human