Administration Strategy-Dependent Mechanisms and Effects of Human Adipose Tissue Stem Cell Extracellular Vesicles in Mouse Allergic Rhinitis Treatment

Abstract

We previously found that intravenous injection of extracellular vesicles (EVs) from human adipose tissue-derived stem cells (hADSC) could ameliorate allergic rhinitis (AR) in mice through immunomodulatory effects. In clinical trials, nasal delivery has been an attractive treatment for AR. We sought to determine whether there are differences in the therapeutic effects between caudal injection and their combination. We treated AR mice with ADSC-EVs via caudal vein, nasal cavity, or both. After treatment, the mice were re-sensitized and the indices of behavior, nasal mucosa morphology, and cytokine secretion of the mice under different modes of administration were calculated. The resultes show that tail vein, nasal, and combined administration could effectively relieve the inflammatory infiltration of the nasal mucosa of mice, reduce the secretion of IgE, IL-4, and other inflammatory factors, and alleviate the Th1/Th2 imbalance. Injection and nasal delivery, as well as their combination, effectively alleviated the symptoms of rhinitis in mice. Nasal administration has a better therapeutic effect when the inflammatory response is mild. It could be speculated that ADSC-EVs have excellent properties in the treatment of AR, and modes of administration can be selected for different stages of treatment in clinical therapy.

Keywords: allergic rhinitis; drug administration strategy; extracellular vesicles; intranasal delivery; vein injection.

Graphical abstract

Figure 1.

Tail vein and intranasal administration of hADSC-EVs had complementary therapeutic effects on AR mouse symptoms and tissue damage. (A) Experimental scheme. (B) Quantification of symptom scores, including sneezing and rubbing in 15 min after final OVA sensitization. (C) H&E staining and quantification of eosinophils in the nasal mucosa. (D) PAS staining and quantification of goblet cells in the nasal mucosa. *P < 0.05; **P < 0.01; ***P < 0.001. Significant difference analysis was performed between AR group and control group, treatment group (VI, ND, and VI+ND group) and AR group. n = 6 or 24.

Figure 2.

hADSC-EVs ameliorated inflammatory environment in AR mice. (A-C) Levels of sIgE (A), IgG4 (B), IL-4 (C), and IFN-γ (C) in the serum measured by ELISA. (D) Relative expression of IFN-γ and IL-4 in the serum by qRT-PCR. *P < 0.05; **P < 0.01; ***P < 0.001. Significant difference analysis was performed between AR group and control group, treatment group (VI, ND, and VI+ND group) and AR group. n = 9.

Figure 3.

The hADSC-EV treatment improved inflammatory environment by restoring the balance Th1/Th2 cells. (A) Flow cytometry analysis of splenic Th1, Th2, and Th17 cells. (B and C) Ratios of Th1/Th2 cells and Th17 calculated according to the results from (A). (D) Relative expression of IL-17 mRNA by qRT-PCR. (E) The radar chart of TEI comparison between the three administration strategies. *P < 0.05; **P < 0.01; ***P < 0.001. Significant difference analysis was performed between AR group and control group, treatment group (VI, ND, and VI+ND group) and AR group. n = 9.

Figure 4.

Partial spontaneous recovery was observed with AR mice during 4-week habituation. (A) Experimental schematic. (B–D) Quantification of sneezing, rubbing, running nose, and symptom scores (including sneezing, rubbing, and runny nose) in 15 min after final OVA sensitization upon 1-week, 2-week, and 4-week treatment. (E) The TEI of PBS in (B-D). (F) Level of IgE, IgG4, IL-4, and IFN-γ in the serum measured by ELISA. *P < 0.05; **P < 0.01; ***P < 0.001.

Figure 5.

Combinatorial administration manifested higher efficacy in reducing AR mouse symptoms for 1- and 2-week treatment schemes. (A) Experimental scheme. (B) Quantification of symptom scores, including sneezing and rubbing 10 min after the final OVA sensitization. (C) H&E staining and PAS staining. (D) Quantification of eosinophils in the nasal mucosa and goblet cells in the nasal mucosa. (E) Levels of sIgE, IFN-γ and IL-4 in the serum measured by ELISA. (F) Relative expression of IFN-γ and IL-4 by qRT-PCR. *P < 0.05; **P < 0.01; ***P < 0.001. Significant difference analysis was performed between AR group and control group, treatment group (VI, ND, and VI+ND group) and AR group. n = 6, 24, or 9.

Figure 6.

Combinatorial administration manifested overall higher therapeutic efficacy for 1- and 2- week treatment schemes. (A) Flow cytometry analysis of Th2 cells in splenic lymphocytes. (B) The ratio of Th1/Th2 cells and Th17 calculated according to the results from A. (C) Relative expression of IL-17 by qRT-PCR. (D) The radar chart of TEI comparison among three routes of delivery after 1-week and 2-week treatment. *P < 0.05; **P < 0.01; ***P < 0.001. Significant difference analysis was performed between AR group and control group, treatment group (VI, ND, and VI+ND group) and AR group. n = 9.