Correlation between T-cell and mast cell activity in patients with chronic urticaria.
BACKGROUND
The presence of autoantibodies reacting with the high affinity IgE receptor (FcepsilonRIalpha) usually indicates a more severe form of chronic urticaria (CU). Previously, we showed an increased lymphocyte reactivity in CU patients; however, the relation between enhanced cellular immunity and the presence of anti-FcepsilonRIalpha-specific autoantibodies has not been investigated.


METHODS
Cellular and humoral immune reactivity of 50 CU patients and 28 healthy controls was studied. Serum sIL-2R, neopterin, and tryptase levels were measured to assess T-cell, monocyte/macrophage and mast cell activity, respectively. Helicobacter pylori (HP)-specific IgG antibody, and IgE levels were also tested. Anti-FcepsilonRIalpha-specific autoantibody was determined by Western blotting. In vivo histamine-releasing activity of patients' sera was assessed by the autologous serum skin test (AST).


RESULTS
17/50 CU patients, who both had IgG-type anti-FcepsilonRIalpha-antibodies by Western blotting and a positive AST response, were classified as autoimmune CU. All patients with CU had significantly higher serum sIL-2R and tryptase levels than healthy controls (p = 0.000257, p = 0.000166, respectively), indicating T-cell and mast cell activation. Patients with higher sIL-2R levels also had higher tryptase levels; the strongest correlation was shown in the autoimmune subgroup of patients (rho = 0.688, p = 0.002). There was a tendency towards higher tryptase levels in the autoimmune subgroup, as compared to the nonautoimmune CU patients. While the serum IgE was significantly lower in autoimmune than in nonautoimmune CU (p = 0.000836), there was no significant difference in their sIL-2R, neopterin and HP-specific IgG antibody levels. CU patients with a positive AST response (38/50) had significantly higher tryptase levels (p = 0.0107) when compared to the negative skin test group.


CONCLUSIONS
The significant correlation between sIL-2R and tryptase levels in patients with CU indicates that T cell activation is proportional to mast cell degranulation in these patients. The increased level of tryptase in autoimmune CU may suggest more severe disease.
Hidvégi
Bernadett
B
Central Laboratory of Immunology, Semmelweis University, Budapest, Hungary. hiber@immun.sote.hu
Nagy
Eszter
E
Szabó
Teréz
T
Temesvári
Erzsébet
E
Marschalkó
Márta
M
Kárpáti
Sarolta
S
Horváth
Attila
A
Gergely
Péter
P
D000293:Adolescent; D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D001323:Autoantibodies / Q000276:immunology; D015153:Blotting, Western; D005260:Female; D016480:Helicobacter pylori / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D008407:Mast Cells / Q000276:immunology* / Q000378:metabolism; D008875:Middle Aged; D019798:Neopterin / Q000097:blood; D017455:Receptors, IgE / Q000276:immunology / Q000378:metabolism; D015375:Receptors, Interleukin-2 / Q000097:blood; D012697:Serine Endopeptidases / Q000097:blood; D012882:Skin Tests; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D053802:Tryptases; D014581:Urticaria / Q000276:immunology* / Q000378:metabolism
D000907:Antibodies, Bacterial; D001323:Autoantibodies; D017455:Receptors, IgE; D015375:Receptors, Interleukin-2; D019798:Neopterin; D012697:Serine Endopeptidases; D053802:Tryptases