Expression and Function of TLR2 on CD4 Versus CD8 T Cells

다국어 초록 (Multilingual Abstract)

Background: Toll-like receptors (TLRs) play a fundamental
role in innate immunity through their capacity to recognize
pathogen-associated molecular patterns. Also, TLRs that are
expressed in T cells are reported to function as co-stimulatory
receptors. However, the functional capacity of TLRs
on CD4 T and CD8 T cells has not been directly compared.
Here we compared CD4 and CD8 T cell responses to TLR2
ligand plus TCR-mediated stimulation. Methods: TLR2 expression
was analyzed on T cell subsets under naïve and alloantigen-
primed conditions. We analyzed the effects of
TLR2 co-stimulation on proliferation and survival of T cell
subsets in vitro when stimulated with soluble anti-CD3 in the
presence or absence of synthetic ligand Pam3CSK4. Results:
TLR2 expression on CD8 T cells was induced following activation;
this expression was much higher than on CD4 T cells.
Thus, the molecule was constitutively expressed on Listeriaspecific
memory CD8 T cells. Based on these expression levels,
proliferation and survival were markedly elevated in CD8
T cells in response to the TLR2 co-stimulation by Pam3CSK4
compared with those in CD4 T cells. Conclusion: Our data
show that TLR2 co-stimulation is more responsible for proliferation
and survival of CD8 T cells than for that of CD4 T
cells.

다국어 초록 (Multilingual Abstract)

Background: Toll-like receptors (TLRs) play a fundamental
role in innate immunity through their capacity to recognize
pathogen-associated molecular patterns. Also, TLRs that are
expressed in T cells are reported to function as co-stimulatory
receptors. However, the functional capacity of TLRs
on CD4 T and CD8 T cells has not been directly compared.
Here we compared CD4 and CD8 T cell responses to TLR2
ligand plus TCR-mediated stimulation. Methods: TLR2 expression
was analyzed on T cell subsets under naïve and alloantigen-
primed conditions. We analyzed the effects of
TLR2 co-stimulation on proliferation and survival of T cell
subsets in vitro when stimulated with soluble anti-CD3 in the
presence or absence of synthetic ligand Pam3CSK4. Results:
TLR2 expression on CD8 T cells was induced following activation;
this expression was much higher than on CD4 T cells.
Thus, the molecule was constitutively expressed on Listeriaspecific
memory CD8 T cells. Based on these expression levels,
proliferation and survival were markedly elevated in CD8
T cells in response to the TLR2 co-stimulation by Pam3CSK4
compared with those in CD4 T cells. Conclusion: Our data
show that TLR2 co-stimulation is more responsible for proliferation
and survival of CD8 T cells than for that of CD4 T
cells.

참고문헌 (Reference)

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