Changes in CD4+CD25+FoxP3+ Regulatory T Cells and Serum Cytokines in Sublingual and Subcutaneous Immunotherapy in Allergic Rhinitis with or without Asthma

Abstract

Background: Few studies have directly compared the immunologic responses to specific subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT).

Objective: We aimed to directly compare clinical efficacy and immunological responses between SLIT and SCIT in allergic rhinitis (AR) sensitized to house dust mites.

Methods: Sixty-seven patients (age 5-55 years) with moderate-severe Dermatophagoides pteronyssinus (Der-p) and Dermatophagoides farinae AR with or without asthma were randomized (2:2:1) into SLIT (n = 27), SCIT (n = 26) and placebo (n = 14) groups. Symptom and medication scores, visual analogue score, serum Der-p specific immunoglobulin G4 (Der-p-sIgG4), CD4+CD25+FoxP3+ regulatory T cells (Tregs) and serum cytokines were measured.

Results: After 1-year treatment, a significant improvement of total rhinitis score (TRS), total rhinitis medication score (TRMS) and visual analogue score occurred in both SLIT and SCIT. There were no differences in clinical efficacy except for TRMS (p = 0.026) when SLIT and SCIT were directly compared. CD4+CD25+FoxP3+ Tregs had a trend towards upregulation in the 2 modes and inversely correlated with TRS (p = 0.024) only in SLIT. Der-p-sIgG4 significantly increased in SLIT and SCIT (p < 0.05), and it was 30 times higher in SCIT than SLIT after the treatment (p < 0.05). Serum interferon-γ significantly increased only in SCIT after 1 (p = 0.008), 6 (p = 0.007) and 12 (p = 0.008) months of treatment and inversely correlated with TRS (p = 0.032).

Conclusion: While SCIT and SLIT have similar rates of clinical improvement, the 2 modes reveal heterogeneous changes of CD4+CD25+Foxp3+ Tregs, sIgG4 and cytokines.

Keywords: Allergic rhinitis; Cytokines; Immunoglobulin G4; Regulatory T cells; Subcutaneous immunotherapy; Sublingual immunotherapy.

Fig. 1

Study design showing the flow of each stage. SCIT, subcutaneous immunotherapy; SLIT, sublingual immunotherapy; SMS, symptom and medication score; VAS, visual analogue scale; sIgE, specific immunoglobulin E; sIgG4, specific immunoglobulin G4; SPT, skin prick test; BPT, bronchial provocation test.

Fig. 2

The levels of biomarkers before and after 12 months of treatment. Paired values for Wilcoxon's signed-rank and Mann-Whitney U test. p value <0.05 is statistically significant. T0, at baseline; T12, at 12 months after treatment; CD4⁺CD25⁺FoxP3⁺ Treg cell (%), the percentage of CD4⁺CD25⁺FoxP3⁺ Treg cells in CD4⁺ T cells. SCIT, subcutaneous immunotherapy; SLIT, sublingual immunotherapy; Der-p, Dermatophagoides pteronyssinus; sIgG4, specific immunoglobulin G4; IFN-γ, interferon-γ; TNF-α, tumour necrosis factor alpha; IL, interleukin.

Fig. 3

The correlation analysis. a–c The correlation between change in IFN-γ and clinical improvement. d–f The correlation between change in TNF-α and clinical improvement. g–i The correlation between the change in Der-p-sIgG4 and clinical improvement. j–l The correlation between the change in rate of CD4⁺CD25⁺FoxP3⁺ Treg cells and clinical improvement. Significance was evaluated by 2-tailed Pearson's correlations analysis. p value <0.05 is statistically significant. TRS, total rhinitis score; Der-p, Dermatophagoides pteronyssinus; sIgG4, specific immunoglobulin G4; SCIT, subcutaneous immunotherapy; SLIT, sublingual immunotherapy; IFN-γ, interferon-γ; TNF-α, tumour necrosis factor alpha.

Fig. 4

The median values for levels of IFN-γ, TNF-α, IL-5 and IL-10 before and 1, 6, and 12 months after initiation of treatment. * p significant increases in serum level of biomarkers were observed in SCIT or SLIT at different points in time when compared with placebo group. SCIT, subcutaneous immunotherapy; SLIT, sublingual immunotherapy; Der-p, Dermatophagoides pteronyssinus; sIgG4, subcutaneous immunotherapy G4; IFN-γ, interferon-γ; TNF-α, tumour necrosis factor alpha; IL, interleukin.