Increased number of T cells committed to IL-5 production after respiratory syncytial virus (RSV) infection of human mononuclear cells in vitro.
We examined changes in the cytokine profile of T cells induced by in vitro infection with RSV. Isolated mononuclear cells from 27 healthy adults and six infants were infected with RSV at a concentration of 3 MOI (multiplicity of infection). After 48 h cells were restimulated with phorbol ester and ionomycin in the presence of monensin for 5 h. The intracellular expression of viral antigen, the cytokines IL-2, IL-4, IL-5, interferon-gamma (IFN-gamma), and the expression of surface markers were assessed by immunofluorescent staining and flow cytometry. There was a significant (P<0.001) rise of IL-5 expression in RSV-infected cultures in comparison with uninfected cultures from the same individuals, whereas there were no changes in the expression of the other lymphokines. The increase in IL-5 generation depended on viable infectious RSV rather than inactivated virus. RSV infection as well as IL-5 production in T cells were confined to the CD8 subpopulation. However, there was no simultaneous expression of RSV antigen and IL-5. Purified T cells did not show any increase in IL-5 generation. However, when the rate of RSV infection was enhanced in monocytes by means of a specific monoclonal antibody, co-cultured T cells displayed an increase of IL-5 production compared with samples with ordinary low rate RSV infection. It is therefore likely that the increased commitment of lymphocytes to produce IL-5 after RSV infection in vitro is mediated by monocytes or other antigen-presenting cells.
Thurau
A M
AM
Klinik für Kinder- und Jugendmedizin der Ruhr Universität Bochum im St Josef Hospital, Germany.
Streckert
H J
HJ
Rieger
C H
CH
Schauer
U
U
D000328:Adult; D000818:Animals; D000938:Antigen-Presenting Cells / Q000502:physiology; D006801:Humans; D007223:Infant; D015848:Interleukin-5 / Q000096:biosynthesis*; D007963:Leukocytes, Mononuclear / Q000821:virology*; D008222:Lymphokines / Q000096:biosynthesis; D051379:Mice; D018113:Respiratory Syncytial Virus, Human / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology*
D015848:Interleukin-5; D008222:Lymphokines