Bovine WC1(-) gammadeltaT cells incubated with IL-15 express the natural cytotoxicity receptor CD335 (NKp46) and produce IFN-gamma in response to exogenous IL-12 and IL-18.
The gammadeltaT cells of ruminants are believed to participate in innate immunity and have been described with regulatory, inflammatory and cytotoxic functions. Here we describe a subset of CD3(+) TcR1(+) WC1(-)gammadeltaT cells expressing CD335 (NKp46), classically associated with CD3(-) natural killer (NK) cells, as a consequence of incubation with IL-15. This population, undetectable at the time of collection, developed after 2 week of IL-15 culture from splenic leukocytes (SPL) reaching greater than 50% of the total gammadeltaT cells. However, they did not grow well from peripheral blood leukocytes (PBL). Splenic gammadeltaT cells positively selected by magnetic separation prior to incubation with IL-15 and analyzed by flow cytometry, consistently yielded CD3(+) cells expressing CD335. These cells arose from the CD335(-)gammadeltaT cell population suggesting that the new population represents up-regulation of CD335 by gammadeltaT cells. CD335 mRNA expression from sorted IL-15-incubated SPL CD335(+)gammadeltaT cells or NK cells exceeded that of CD335(-)gammadeltaT cells. Incubation with IL-12 and IL-18 increased the number of CD335(+)gammadeltaT cells in both the PBL and SPL fractions as compared to controls or IL-12 or IL-18 alone. In addition, CD335(+)gammadeltaT cells demonstrated a robust ability to produce IFN-gamma in response to exogenous IL-12 and IL-18. Taken as a whole, we describe a new phenotypically distinct bovine gammadeltaT cell sub-population capable of participating in type 1 immune responses.
Johnson
Wendell C
WC
Animal Disease Research Unit, USDA-ARS, Washington State University, Pullman, WA 99164-6630, USA.
Bastos
Reginaldo G
RG
Davis
William C
WC
Goff
Will L
WL
D000818:Animals; D002417:Cattle / Q000276:immunology*; D002478:Cells, Cultured; D016130:Immunophenotyping; D007371:Interferon-gamma / Q000096:biosynthesis*; D018664:Interleukin-12 / Q000494:pharmacology*; D019409:Interleukin-15 / Q000494:pharmacology*; D020382:Interleukin-18 / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000032:analysis*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*
C086500:DMBT1 protein, Bos taurus; D019409:Interleukin-15; D020382:Interleukin-18; D008562:Membrane Glycoproteins; D016692:Receptors, Antigen, T-Cell, gamma-delta; D018664:Interleukin-12; D007371:Interferon-gamma