Patients with allergic contact dermatitis to nickel and nonallergic individuals display different nickel-specific T cell responses. Evidence for the presence of effector CD8+ and regulatory CD4+ T cells.
To investigate the mechanisms underlying the expression of allergic contact dermatitis, we compared the characteristics of nickel (Ni)-specific T cell responses in 10 patients with allergic contact dermatitis to Ni and in 10 healthy, nonallergic individuals. CD4+ T cells purified from peripheral blood of both allergic and nonallergic subjects proliferated similarly to NiSO4 in vitro, with the responses mostly restricted to CD4+ CD45RO+ memory T cells. In contrast, Ni-specific CD8+ T cell responses were detected only in allergic patients. Limiting dilution assay confirmed a high frequency of Ni-specific CD4+ T cells in both individual categories, and of Ni-specific CD8+ T cells in allergic patients, but not in nonallergic persons. Ni-specific CD4+ T cell clones prepared from nonallergic subjects displayed lower interferon-gamma and higher interleukin-10 production compared with T cell clones from allergic patients. The T cell skin-homing receptor, cutaneous lymphocyte-associated antigen, was expressed on the large majority of specific CD4+ clones from both the groups. Finally, Ni-specific CD8+ clones prepared from patients also expressed the cutaneous lymphocyte-associated antigen receptor, and released high interferon-gamma and no interleukin-4. In aggregate, the results suggest that the presence of specific CD8+ T cells and a distinct pattern of cytokine release (e.g., an augmented production of interleukin-10) by CD4+ T cells can be important elements in determining whether a hapten induces allergy or a silent immune response.
Laboratory of Immunology, Istituto Dermopatico dell'Immacolata, IRCCS, Rome, Italy.
A
A
Cavani
D
D
Mei
E
E
Guerra
S
S
Corinti
M
M
Giani
L
L
Pirrotta
P
P
Puddu
G
G
Girolomoni
D000328:Adult; D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D002455:Cell Division / Q000187:drug effects; D017449:Dermatitis, Allergic Contact / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D003877:Dermatitis, Contact / Q000209:etiology / Q000276:immunology* / Q000473:pathology; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D007509:Irritants / Q000494:pharmacology; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis; D009532:Nickel / Q000009:adverse effects* / Q000494:pharmacology; D010641:Phenotype; D016176:T-Lymphocyte Subsets / Q000378:metabolism
D000945:Antigens, Differentiation, T-Lymphocyte; D000951:Antigens, Neoplasm; C063419:CTAGE1 protein, human; D007509:Irritants; D008562:Membrane Glycoproteins; D016753:Interleukin-10; C029938:nickel sulfate; D009532:Nickel; D007371:Interferon-gamma