T lymphocytes from tonsil and peripheral blood show different cytolytic and helper activities.
T lymphocytes from tonsil (To) and peripheral blood (PB) of 4 tonsillectomized children were subjected to clonal expansion with PHA in order to analyze at single cell level their cytolytic activity and their ability to produce interleukins such as IL-2, IFN-gamma and IL-4. Analyzing all T-cell clones (CD4+ and CD8+) obtained from To in comparison with those from PB, a reduced proportion of cells with lectin-dependent cytolytic activity (LDCC) (25% vs. 42%, p less than 0.01) and natural killer (NK) activity (18% vs. 31%, p less than 0.02) was found. These differences were proportionally related to the lower number of CD8+ T-cells in To than in PB. The proportion of CD4+ clones able to produce IL-2 and/or IL-4 were higher in To (75% and 61%) than in PB (52% and 25%, p less than 0.001 and p less than 0.001, respectively). In contrast, the proportion of CD4+ clones able to produce IFN-gamma was similar (53% and 58%) in both series of clones. According to the patterns of lymphokine synthesis, tonsillar T-cells differed from PB T-cells as follows: 1) the number of Th1-like CD4+ clones producing IL-2 and/or IFN-gamma (but not IL-4) were 23% vs. 44% in PB (p less than 0.001); 2) there was no difference between To and PB in the proportion of CD4+ clones producing IL-4 alone (Th2 clones: 9% vs. 8%); 3) CD4+ clones synthesizing IL-2, IL-4 and IFN-gamma at the same time were more frequent in To than in PB (Th3 clones: 53% vs. 17%, p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
II ORL Clinic, University of Florence, Italy.
O
O
Gallo
M
M
De Carli
E
E
Gallina
G
G
Toccafondi
S
S
Romagnani
G
G
Del Prete
D000293:Adolescent; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D002648:Child; D002999:Clone Cells; D006801:Humans; D007378:Interleukins / Q000096:biosynthesis; D007694:Killer Cells, Natural / Q000276:immunology*; D008213:Lymphocyte Activation / Q000276:immunology; D014066:Palatine Tonsil / Q000276:immunology* / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014069:Tonsillitis / Q000473:pathology
D007378:Interleukins