[Effect of TLR ligand (R-848) and IL-12 on the production of IFN-gamma by human NK cell subsets].
OBJECTIVE
To investigate the effect of the TLR ligand (R-848) and IL-12 on the production of IFN-gamma by human NK cell subsets.


METHODS
PBMC or purified NK cells were isolated from normal human peripheral blood and cultured with R-848, IL-12 , R-848+ IL-12. The level of IFN-gamma in the culture supernatants was measured by ELISA. The cell subsets which produced IFN-gamma were detected and analyzed by flow cytometry(FCM).


RESULTS
PBMC cultured with different concentrations of TLR ligands (R-848, LPS and CpG) could induce IFN-gamma production in a dose dependent manner. Among these three TLR ligands, R-848 was the best one in induction of IFN-gamma production by PBMC. FCM analysis indicated that R-848 could induce IFN-gamma expression by CD56(+) cells, but not CD4(+) or CD8(+) T cells. Similarly, IL-12 could stimulate NK cells to produce IFN-gamma. In addition, R-848 and IL-12 had synergistic effect on the production of IFN-gamma by PBMC and purified NK cells including CD56(bright) and CD56(dim) subsets.


CONCLUSIONS
Engagement of TLR7/8 by R-848 stimulation with IL-12 could induce IFN-gamma production by CD56(bright) NK cells which indicated that TLRs and cytokines played an important role in the regulation of biologic function of NK cells.
Yin
Ling-fan
LF
Department of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China. yinlingfan2003@yahoo.com.cn
Fan
Yan-ying
YY
Li
Li
L
Wu
Chang-you
CY
D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D019002:CD56 Antigen / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology*; D007371:Interferon-gamma / Q000378:metabolism*; D018664:Interleukin-12; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000378:metabolism*; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism; D051193:Toll-Like Receptors / Q000819:agonists*
D019002:CD56 Antigen; D007093:Imidazoles; D051193:Toll-Like Receptors; D018664:Interleukin-12; D007371:Interferon-gamma; C402365:resiquimod