Effects of CD4(+)CD25(+)Foxp3(+)regulatory T cells on early Plasmodium yoelii 17XL infection in BALB/c mice.
The outcome of Plasmodium yoelii 17XL-infected BALB/c and DBA/2 mice, ranging from death to spontaneous cure, respectively, depends largely on the establishment of effective pro-inflammatory type 1 responses during the early stages of infection and associates with CD4(+)CD25(+)Foxp3(+)regulatory T cells (Tregs). Here, effects of Tregs were analysed on early P. yoelii 17XL infection in BALB/c and DBA/2 mice. In vivo depletion of Tregs significantly reversed the inhibited establishment of effective pro-inflammatory type 1 responses in BALB/c mice, indicating that this cell population contributed to the suppression of T-cell function in malaria. Moreover, the proportion and absolute numbers of IL-10-secreting Tregs in BALB/c mice were significantly higher than that found in DBA/2 mice by intracytoplasmic staining, and IL-10 production was correlated with the Tregs population. In addition, in vivo Tregs depletion decreased the production of IL-10 and the apoptosis of CD4+ T cells. Consistently, IL-10R blockade also had the same effect as that of Tregs depletion in P. yoelii 17XL-infected BALB/c mice. Our data demonstrate that Tregs perhaps have an important role in regulating pro-inflammatory type 1 responses in an IL-10-dependent manner and induce CD4+ T cell apoptosis during the early stage of P. yoelii 17XL infection.
Chen
Guang
G
Department of Immunology, College of Basic Medical Sciences, China Medical University, Heping District, Shenyang, China.
Liu
Jun
J
Wang
Qing-Hui
QH
Wu
Yi
Y
Feng
Hui
H
Zheng
Wei
W
Guo
Sheng-Yu
SY
Li
Dong-Mei
DM
Wang
Ji-Chun
JC
Cao
Ya-Ming
YM
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D051858:Forkhead Transcription Factors / Q000378:metabolism*; D016753:Interleukin-10 / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism*; D008288:Malaria / Q000276:immunology* / Q000401:mortality / Q000469:parasitology / Q000503:physiopathology; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D018512:Parasitemia / Q000276:immunology / Q000401:mortality / Q000469:parasitology; D010967:Plasmodium yoelii / Q000472:pathogenicity*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
D051858:Forkhead Transcription Factors; C498833:Foxp3 protein, mouse; D053645:Interleukin-2 Receptor alpha Subunit; D016753:Interleukin-10