Augmentation of regulatory T cells in allergic individuals by recombinant Der f 2 peptide with fungal immunomodulatory peptide fve.
BACKGROUND
The suppressive function of regulatory T (Treg) cells is compromised in allergic individuals, and the augmentation of Treg cells has been demonstrated after successful allergen immunotherapy.


OBJECTIVE
To evaluate the effect of Dermatophagoides farinae fragments (Der f 2 N-peptides) that do not bind specific IgE in conjunction with the fungal immunomodulatory peptide fve (FIP-fve) on Treg cells derived from individuals with allergic rhinitis.


METHODS
CD4+CD25+ T cells were isolated from peripheral blood mononuclear cells of 11 patients with allergic rhinitis and 7 nonallergic individuals using immunomagnetic beads. Cells were cultured with medium, Der f 2, FIP-fve, FIP-fve plus Der f 2, and FIP-fve plus Der f 2 N-peptides for 6 days in the presence of antigen-presenting cells. The percentages and function of Foxp3+CD4+CD25+ Treg cells, interleukin (IL) 10+, and transforming growth factor beta (TGF-beta)+ Treg cells were measured.


RESULTS
The percentage of Foxp3+ Treg cells in CD4+CD25+ T cells was significantly increased in D farinae allergic patients by Der f 2 N-peptides in conjunction with FIP-fve. Both IL-10+ and TGF-beta+ Treg cells were significantly increased in the presence of Der f 2 N-peptides and FIP-fve compared with other groups. The function of Treg cells induced by Der f 2 N-peptides and FIP-fve could be demonstrated by the inhibition of bromodeoxyuridine uptake by peripheral blood mononuclear cells.


CONCLUSIONS
The percentage of IL-10+ and TGF-beta+ cells in Foxp3+CD4+CD25+ T cells can be up-regulated by Der f 2 N-peptides in conjunction with FIP-fve only in D farinae allergic individuals. These results indicate that non-IgE-mediated fragments of allergen in conjunction with FIP-fve might have therapeutic effects on Treg cells derived from allergic individuals.
Department of Medical Education and Research, Taichung Veterans General Hospital, Taichung, Taiwan, Republic of China.
Chia-Chuan
CC
Wu
En-Chih
EC
Liao
Mey-Fann
MF
Lee
Jaw-Ji
JJ
Tsai
D039741:Antigens, Dermatophagoides / Q000235:genetics / Q000276:immunology*; D060829:Arthropod Proteins; D016022:Case-Control Studies; D049109:Cell Proliferation; D016207:Cytokines / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000276:immunology*; D006801:Humans; D016753:Interleukin-10 / Q000378:metabolism; D037102:Lectins / Q000235:genetics / Q000276:immunology*; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D010446:Peptide Fragments / Q000235:genetics / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology*; D012221:Rhinitis, Allergic, Perennial / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000378:metabolism
D039741:Antigens, Dermatophagoides; D060829:Arthropod Proteins; D016207:Cytokines; C451160:Dermatophagoides farinae antigen f 2; D005656:Fungal Proteins; C508609:IL10 protein, human; D037102:Lectins; D010446:Peptide Fragments; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D016753:Interleukin-10