To explore the effect of acupuncture at Zusanli (Stomach-36, ST36) on alleviating experimental autoimmune encephalomyelitis (EAE) by regulating immune cells and cytokines of peripheral immune system.

Experimental mice were randomly divided into EAE group and acupuncture group. The body weight and clinical symptom of the experimental mice were monitored. The infiltration of inflammatory cells in spinal cord was detected by hematoxylin-eosin staining (HE) staining, and demyelination was detected by immunofluorescence. The proportion of T cell subtypes was detected by flow cytometry, and the concentration of related cytokines in peripheral serum was detected by Meso scale discovery (MSD).

EAE mouse model was successfully constructed and treated with acupuncture. The clinical score showed that EAE group reached the peak on the 22nd day with the score of 2.5 points. Acupuncture group reached the peak on the 24th day with the score of 2 points. The onset time of EAE group began on the 12th day, and that of acupuncture group began on the 17th day. The onset time of acupuncture group was later than that of EAE group. The results of HE and immunofluorescence showed that the spinal cord inflammatory cell infiltration was less, the myelin sheath structure was complete and the edge was smooth in the acupuncture group. The results of flow cytometry showed that the proportion of CD4⁺ IFN-γ⁺ T cells and CD4⁺ IL-17⁺ T cells in acupuncture group was decreased significantly compared with EAE group [(0.49±0.10)% vs (0.92±0.25)%, (0.21±0.05)% vs (0.34±0.04)%, t values were 2.91 and 3.70 respectively, both P values<0.05]. The proportion of CD4⁺ IL-4⁺ T, CD4⁺ Foxp3⁺ and CD8⁺ Foxp3⁺ cells in acupuncture group was significantly higher than that in EAE group [(0.78±0.22)% vs (0.5±0.07)%, (1.38±0.23)% vs (0.9±0.08)%, (0.38±0.12)% vs (0.14± 0.09)%, t values were 2.55, 3.35 and 4.16 respectively, all P values <0.05]. The results of peripheral serum cytokines detected by MSD showed that the concentrations of anti-inflammatory cytokines interleukin (IL)-5 and IL-16 in acupuncture group were significantly higher than those in EAE group, and the concentration of pro-inflammatory cytokines IFN-γ was significantly lower than that in EAE group [(4.53±0.95) pg/mL vs (2.78±1.25) pg/mL, (2298.77±298.67) pg/mL vs (1402.28± 216.30) pg/mL, (6.6±0.548) pg/mL vs (8.84±0.98) pg/mL, t values were 9.00, 4.84 and 3.57 respectively, all P values <0.05)]. The results of this study showed that acupuncture treatment may inhibit the proportion of helper T cell (th) 1/Th17, promot the percentage of Th2, and increase the proportion of regulatory T cell (Treg). In addition, acupuncture treatment also can promote the expression of anti-inflammatory factors IL-5 and IL-16, and inhibit the expression of pro-inflammatory factor interferon-γ(IFN-γ).

Acupuncture ST36 could alleviate EAE by correcting the imbalance of T cell subtypes and regulating the expression of cytokines.

Experimental autoimmune encephalomyelitis; Acupuncture; Stomach-36; T cell subtypes; Cytokines