文献阅读002|PD1/PD-L1的发现与研究

PD1/PD-L1

Nature, 2006

1. PD-1 is upregulated during chronic viral infection

acute/chronic infections in adult mice: LCMV different strain

microarray analysis of genes expressed
by LCMV-specific CD8 T cells

Kinetics of PD-1 expression on CD8 T cells

2. PD-L1 blockade enhances viral control and T-cell responses

LCMV clone-13-infected mice were treated with anti-PD-L1 from day 23 to day 37 post-infection

Test:

A. Virus-specific CD8 T-cell numbers in the spleen

B. Cytokine production(IFN、TNF)by splenocytes after stimulation

C.  Viral titers in the tissues

PD-L1 blockade did not increase virus-specific CD8 T-cell responses in the acute infection model (data not shown).

3. Restoring function in ‘helpless’ CD8 T cells

whether blockade of the PD-1/PD-L1 inhibitory pathway would enhance CD8 T-cell responses in the absence of CD4 T cell help？

Mice were depleted of CD4 T cells and then infected with LCMV clone 13. After at least 40 days, chronically infected mice were treated with anti-PD-L1 for two weeks.

Test:

A. Virus-specific CD8 T-cell numbers in the spleen and other tissues

B. Cytokine production (IFN) by splenocytes after stimulation

C. Viral titers in the tissues

D. BrdU incorporation and Ki67 expression: 变多的T细胞是否是增殖而来？

E. Direct ex vivo 51Cr-release activity using target cells coated with epitopes：CTL的裂解能力？

F. degranulation by LCMV-specific CD8 T cells：CTL的裂解能力？

Treatment of chronically infected mice with anti-CTLA-4 blocking antibody had no effect on either virus-specific T-cell responses or viral control.

4. Proliferation of exhausted CD8 T cells

whether exhausted CD8 T cells self-renew or proliferate from naive T cells? 变多的CD8 T cell从何而来？

CFSE-labelled splenocyte transfer to receptor mice

发现donor exhausted CD8+ T cell的数量变多，说明PD-1可以使exhausted的细胞增殖，但不排除可能存在naive T cell对增殖的贡献，所以进一步分选PD-1+ CD8 T cell，如下：

PD-1+ CD8 T cell排除未exhausted的T cell的影响

Expanded population of virus specific CD8 T cells does not suddenly decline after the antibody treatment has been stopped.

5. Infection of PD-L1-/- mice

PD-1 KO mice