A clonal analysis of lung T cells derived by bronchoalveolar lavage of healthy individuals.
The characteristics of the T-cell population in the healthy human lung have been investigated by analysing the properties of T-cell clones derived from bronchoalveolar lavage (BAL) samples and comparing them with T cells cloned from the blood of the same individuals. The proportions of CD4+ and CD8+ T cells in the starting populations from BAL and blood were similar although only 14% of BAL T cells were CD45RA+ compared to 70% of blood T cells. The precursor frequency of T-cell clones derived from BAL was less than from blood. The cytokine profiles [after phytohaemagglutinin (PHA) stimulation] of the clones derived from both sources were markedly different and these differences lay in the CD4+ population. BAL-derived CD4+ clones produced interferon-gamma (IFN-gamma) more frequently than did those from blood while blood-derived clones were more likely to produce interleukin-2 (IL-2) than those from BAL. IL-4 was produced by the majority of BAL- or blood-derived clones (93% and 88% respectively) either along with IFN-gamma (BAL) or IL-2 (blood). The cytokine profiles of BAL-derived T-cell clones are consistent with those derived from lung interstitium and suggest that the BAL T-cell populations reflect those in the lung wall. Whether the unique properties of lung T cells are acquired after leaving the blood or whether there is selective entry of T-cell subpopulations into the lung remains to be determined.
Department of Medicine, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands.
M J
MJ
Garlepp
A H
AH
Rose
R V
RV
Bowman
N
N
Mavaddat
J
J
Dench
B J
BJ
Holt
M
M
Baron-Hay
P G
PG
Holt
B W
BW
Robinson
D000328:Adult; D000368:Aged; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology*; D015704:CD4 Antigens / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016827:CD8 Antigens / Q000032:analysis; D002999:Clone Cells / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D008168:Lung / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D013601:T-Lymphocytes / Q000276:immunology*
D015704:CD4 Antigens; D016827:CD8 Antigens; D016207:Cytokines; D007376:Interleukin-2; D007371:Interferon-gamma