Increased Interleukin-4 production by CD8 and gammadelta T cells in health-care workers is associated with the subsequent development of active tuberculosis.
We evaluated immune responses to Mycobacterium tuberculosis in 10 health-care workers (HCWs) and 10 non-HCWs and correlated their immune status with the development of active tuberculosis (TB). Twenty individuals were randomly recruited, tested, and monitored longitudinally for TB presentation. Peripheral blood mononuclear cells (PBMCs) from donors were stimulated with M. tuberculosis and tested for cell proliferation and the production of interferon (IFN)- gamma, interleukin (IL)-5, and IL-4, by use of enzyme-linked immunosorbent or flow-cytometric assays. HCWs had higher levels of cell proliferation (24,258 cpm) and IFN- gamma (6373 pg/mL) to M. tuberculosis than did non-HCWs (cell proliferation, 11,462 cpm; IFN- gamma, 3228 pg/mL). Six of 10 HCWs showed increased median percentages of CD8+IL-4+ (4.7%) and gammadelta +IL-4+ (2.3%) T cells and progressed to active TB. HCWs who remained healthy showed increased median percentages of CD8+IFN- gamma+ (25.0%) and gammadelta +IFN- gamma+ (8.0%) and lower percentages of CD8+IL-4+ (0.05%) and gammadelta +IL-4+ (0.03%) T cells.
Centro de Malaria e Outras Doencas Tropicais, Unit of Mycobacteriology/Instituto de Higiene e Medicina Tropical, Universidade de Lisboa, Hospital Egas Moniz, Lisbon, Portugal. dordway@lamar.colostate.edu.
Diane J
DJ
Ordway
Leonor
L
Costa
Marta
M
Martins
Henrique
H
Silveira
Leonard
L
Amaral
Maria J
MJ
Arroz
Fernando A
FA
Ventura
Hazel M
HM
Dockrell
D000328:Adult; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002455:Cell Division; D003695:Delivery of Health Care; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis*; D015848:Interleukin-5 / Q000096:biosynthesis; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000382:microbiology; D008137:Longitudinal Studies; D008297:Male; D009169:Mycobacterium tuberculosis; D011174:Portugal; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D013045:Species Specificity; D014376:Tuberculosis / Q000097:blood / Q000175:diagnosis*; D000078329:Workforce
D015848:Interleukin-5; D016692:Receptors, Antigen, T-Cell, gamma-delta; D015847:Interleukin-4; D007371:Interferon-gamma