Acupuncture Regulates the Balance of CD4⁺ T Cell Subtypes in Experimental Asthma Mice

To evaluate the involvement of different CD4⁺ T cell subtypes in the anti-asthmatic effects of acupuncture in asthmatic mice.

BALB/c mice were challenged by ovalbumin (OVA) for the establishment of experimental asthma model. Mice were divided into 4 groups by a random number table including the normal control, asthma model, acupuncture and sham acupuncture groups (14 per group). Acupoints Dazhui (GV 14), bilateral Fengmen (BL 12) and Feishu (BL 13) were selected for manual acupuncture treatment every other day for 4 weeks and Huantiao (GB 30) was selected for sham acupuncture. Airway hyperresponsiveness was examined by Buxco Pulmonary System. Pulmonary histopathology analysis was performed for inflammatory cell infiltration and mucus hypersecretion by haematoxylin eosin staining and periodic acid-Schiffstaining. Inflammatory mediators assays of serum were investigated by enzyme-linked immunosorbent assay and Bio-Plex. CD4⁺ T cell subpopulations including the expression levels of important factors in T lymphocyte polarization in lung tissue were examined by flow cytometric and Western blot analyses. Related pathways were detected by Western blot assay.

Compared with the OVA-induced asthma model group, acupuncture could attenuate airway hyperresponsiveness, inhibit inflammatory cell infiltration and mucus hypersecretion (P<0.05 or P<0.01). Furthermore, acupuncture increased the expressions of T-bet and Foxp3⁺, the cell numbers of CD4⁺ interferon gamma (IFN-γ)⁺ and CD4⁺ Foxp3⁺ in lung tissue and the level of Treg type cytokine interleukin (IL)-10 in serum (P<0.05 or P<0.01). Meanwhile, acupuncture reduced the RAR-related orphan receptor gamma t (RORγt) level, the cell numbers of CD4⁺ IL-17A⁺ as well as the levels of IL-5, IL-13 and IL-17A in serum (P<0.05 or P<0.01). In addition, both acupuncture and sham acupuncture could inhibit the phosphorylation of p38 and p44/42 (P<0.01).

Acupuncture could alleviate allergic airway inflammation by strengthening the activities of Th1 and Treg, thus regulating the balance of CD4⁺ T cell subtypes in experimental asthmatic mice.