Objective:

2

To determine the role of

Tripterygium wilfordii

multiglycoside (TGW) in the treatment of psoriatic dermatitis from a cellular immunological perspective.

Methods:

2

Mouse models of psoriatic dermatitis were established by imiquimod (IMQ). Twelve male BALB/c mice were assigned to IMQ or IMQ+TGW groups according to a random number table. Histopathological changes

in vivo

were assessed by hematoxylin and eosin staining. Ratios of immune cells and cytokines in mice

as well as PAM212 cell proliferation

in vitro

were assessed by flow cytometry. Pro-inflammatory cytokine expression was determined using reverse transcription quantitative polymerase chain reaction.

Results:

2

TGW significantly ameliorated the severity of IMQ-induced psoriasis-like mouse skin lesions and restrained the activation of CD45

+

cells

neutrophils and T lymphocytes (all

P

<

0.01). Moreover

TGW significantly attenuated keratinocytes (KCs) proliferation and downregulated the mRNA levels of inflammatory cytokines including interleukin (IL)-17A

IL-23

tumor necrosis factor α

and chemokine (C-X-C motif) ligand 1 (

P

<

0.01 or

P

<

0.05). Furthermore

it reduced the number of γδT17 cells in skin lesion of mice and draining lymph nodes (

P

<

0.01).

Conclusions:

2

TGW improved psoriasis-like inflammation by inhibiting KCs proliferation

as well as the associated immune cells and cytokine expression. It inhibited IL-17 secretion from γδT cells

which improved the immune-inflammatory microenvironment of psoriasis.