R. Boismenu et al., CHEMOKINE EXPRESSION BY INTRAEPITHELIAL GAMMA-DELTA T-CELLS - IMPLICATIONS FOR THE RECRUITMENT OF INFLAMMATORY CELLS TO DAMAGED EPITHELIA, The Journal of immunology, 157(3), 1996, pp. 985-992
T cells expressing gamma delta TCR may have evolved to recognize Ag in
a different manner as well as perform a broader set of functions than
T cells with alpha beta TCR. In this study, we tested the hypothesis
that dendritic epidermal T cells (DETC) bearing the invariant V gamma
3V delta 1 TCR may be able to signal the migration of peripheral alpha
beta T cells to the epidermis by secreting specific chemokines. Expre
ssion of macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, RA
NTES, and lymphotactin was inducible in DETC 7-17 cells, whereas mRNA
for monocyte chemoattractant protein (MCP)-1 could not be detected. St
rikingly, lymphotactin was the most abundant chemokine produced by act
ivated DETC 7-17 cells. Activated primary DETC cultures also produced
copious amounts of lymphotactin mRNA, Similarly, freshly isolated and
activated intestinal intraepithelial T cells (i-IEL) with gamma delta
TCR expressed high levels of lymphotactin mRNA, In contrast, lymphotac
tin mRNA was present in activated spleen gamma delta T cells at low ba
sal levels. Migration of CD8(+)T cells induced by culture supernatants
from stimulated DETC 7-17 cells was strongly reduced in the presence
of a neutralizing anti-lymphotactin antiserum and to a lesser extent b
y neutralizing anti-MIP-1 alpha, anti-MIP-1 beta, or anti-RANTES antis
erum. The presence of lymphotactin in supernatants from activated DETC
7-17 cultures was directly demonstrated by Western blot analysis, The
se observations are consistent with a model in which gamma delta IEL p
lay an active multifaceted role in the maintenance of epithelia homeos
tasis.