Effect of autologous whole blood injections on expression of FcεRI and CD63 on basophils in patients with refractory chronic spontaneous urticaria and positive autologous serum skin test

Objective To evaluate the clinical efficacy of autologous whole blood injections (AWBI) combined with antihistamines for the treatment of patients with refractory chronic spontaneous urticaria and positive autologous serum skin test (ASST) , to evaluate its effect on the expression of the high- affinity IgE receptor (FceRⅠ) and CD63 on basophils, and to analyze the possible mechanism underlying the treatment of ASST-positive chronic urticaria with AWBI. Methods Eighty patients with ASST-positive chronic intractable urticaria were enrolled from Department of Dermatology, The First Hospital Affiliated to Army Medical University between November 2017 and June 2018, and randomly and equally divided into two groups by a random number table: AWBI group and control group were both conventionally treated with oral loratadine and ebastine, and AWBI group were additionally treated with AWBI once a week for 12 sessions. Before the treatment and after 12-week treatment, urticaria activity score of 7 days (UAS7) and dermatology life quality index (DLQI) in the two groups were evaluated. Among 30 patients in the AWBI group, flow cytometry was performed to determine the expression of FceRⅠ and CD63 on the basophils in the peripheral blood at the baseline, weeks 4, 8 and 12 after the initial treatment. Statistical analysis was carried out with GraphPad Prism 7.00 software by t test for the comparison of UAS7 or DLQI scores, Mann-Whitney U test for the comparison of FceRⅠα expression, paired Wilcoxon signed rank test for comparing FceRⅠα or CD63 expression between two different time points, and Spearman correlation analysis for analyzing the correlation between FceRⅠα and CD63 expression. Results Before the treatment, no significant differences in UAS7 or DLQI scores were observed between the AWBI group and control group (UAS7: 27.15 ± 4.53 vs. 26.90 ± 5.22; DLQI: 16.88 ± 6.01 vs. 17.08 ± 6.79; both P > 0.05) . After 12-week treatment, UAS7 and DLQI scores both significantly decreased in the two groups compared with those before the treatment (all P < 0.01) , and were significantly lower in the AWBI group than in the control group (UAS7: 14.25 ± 7.56 vs. 19.93 ± 6.32; DLQI: 8.48 ± 4.15 vs. 13.93 ± 5.43; both P < 0.01) . At the baseline, weeks 4, 8 and 12 after the initial treatment, the fluorescence intensities of FceRⅠα on basophils (M [P25, P75]) in the AWBI group were 22 532 (16 740, 29 220) , 16 911 (10 240, 21 816) , 13 282 (7 600, 16 848) and 11 466 (7 161, 14 578) respectively, and the proportions of CD63+ basophils induced by ASST-positive serum (M [P25, P75]) in the AWBI group were 35.25% (26.75%, 49.13%) , 25.95% (19.37%, 37.54%) , 13.57% (7.79%, 19.57%) and 9.87% (6.43%, 16.52%) respectively. At week 4 after the initial treatment, the expression of FceRⅠα and CD63 on basophils in the AWBI group both significantly decreased compared with those at the baseline (both P < 0.01) , but significantly increased compared with those at week 8 (both P < 0.01) . The changes in FceRⅠα expression from baseline to week 4, from week 4 to week 8, and from week 8 to week 12 were positively correlated with the changes in CD63 expression induced by ASST-positive serum (r = 0.364, 0.422, 0.455, respectively, all P < 0.05) . Conclusion AWBI combined with antihistamines can improve the clinical symptoms of ASST-positive refractory chronic urticaria, likely by affecting the expression of FceRⅠand CD63 on basophils. Key words: Urticaria; Blood transfusion, autologous; Receptors, IgE; Basophil degranulation test; Antigens, CD63; Chronic spontaneous urticaria; Autologous whole blood injection