BACKGROUND: Circulating functional autoantibodies to the high-affinity IgE receptor (Fc(epsilon)RI) or to IgE have been found in approximately one third of patients with chronic idiopathic urticaria (CIU). OBJECTIVE: We sought to compare basophil histamine release and basophil numbers in patients with CIU with and without autoantibodies. METHODS: Basophil histamine release to the anti-Fc(epsilon)RI mAb 22E7, anti-IgE, and formyl-methionyl-leucyl-phenylalanine (fMLP); basophil numbers; and total cellular histamine were measured in 26 patients with CIU and 18 healthy control subjects. Twelve patients were classified as having functional anti-Fc(epsilon)RI and/or anti-IgE autoantibodies on the basis of their serum-evoked histamine release from the basophils of 2 healthy donors. RESULTS: 22E7 and anti-IgE, but not fMLP, released less histamine from basophils of patients with CIU than from those of control subjects. Mean+/-SEM maximum histamine release to 22E7 from basophils of control subjects and patients with CIU with and without autoantibodies was 38.5%+/-5.0%, 17.9%+/-6.0% (P =.01), and 1.0%+/-0.3% (P <.0001), respectively. Similar results were obtained with anti-IgE, which is dependent on and cross-links cell bound IgE, and 22E7, which directly cross-links the IgE receptor. The mean+/-SEM basophil counts for control subjects and patients with CIU without and with autoantibodies were 52+/-7, 34+/-9 (P =.04), and 5+/-1 (P <.0001) x 10(6) cells/L, respectively, and similar changes were found in measurements of total cellular histamine. CONCLUSION: Patients with autoantibodies have both markedly reduced basophil numbers and basophil histamine release to factors acting through Fc(epsilon)RI, which indicates either a residual pool of functionally distinct basophils or may be a consequence of desensitization of the Fc(epsilon)RI pathway.
BACKGROUND: Circulating functional autoantibodies to the high-affinity IgE receptor (Fc(epsilon)RI) or to IgE have been found in approximately one third of patients with chronic idiopathic urticaria (CIU). OBJECTIVE: We sought to compare basophil histamine release and basophil numbers in patients with CIU with and without autoantibodies. METHODS: Basophil histamine release to the anti-Fc(epsilon)RI mAb 22E7, anti-IgE, and formyl-methionyl-leucyl-phenylalanine (fMLP); basophil numbers; and total cellular histamine were measured in 26 patients with CIU and 18 healthy control subjects. Twelve patients were classified as having functional anti-Fc(epsilon)RI and/or anti-IgE autoantibodies on the basis of their serum-evoked histamine release from the basophils of 2 healthy donors. RESULTS: 22E7 and anti-IgE, but not fMLP, released less histamine from basophils of patients with CIU than from those of control subjects. Mean+/-SEM maximum histamine release to 22E7 from basophils of control subjects and patients with CIU with and without autoantibodies was 38.5%+/-5.0%, 17.9%+/-6.0% (P =.01), and 1.0%+/-0.3% (P <.0001), respectively. Similar results were obtained with anti-IgE, which is dependent on and cross-links cell bound IgE, and 22E7, which directly cross-links the IgE receptor. The mean+/-SEM basophil counts for control subjects and patients with CIU without and with autoantibodies were 52+/-7, 34+/-9 (P =.04), and 5+/-1 (P <.0001) x 10(6) cells/L, respectively, and similar changes were found in measurements of total cellular histamine. CONCLUSION:Patients with autoantibodies have both markedly reduced basophil numbers and basophil histamine release to factors acting through Fc(epsilon)RI, which indicates either a residual pool of functionally distinct basophils or may be a consequence of desensitization of the Fc(epsilon)RI pathway.
Authors: J C Santos; C A de Brito; E A Futata; M H Azor; N M Orii; C W Maruta; E A Rivitti; A J S Duarte; M N Sato Journal: Clin Exp Immunol Date: 2012-01 Impact factor: 4.330
Authors: Sarbjit S Saini; Miya Paterniti; Kavitha Vasagar; Scott P Gibbons; Patricia M Sterba; Becky M Vonakis Journal: Clin Immunol Date: 2009-05-27 Impact factor: 3.969