Whiteside Sarah, Markova Marketa, Chin Alex, Lam Cynthia, Dharmani-Khan Poonam, Modi Monica, Khan Faisal, Storek Jan
Department of Medicine, University of Calgary, Calgary, Alberta, Canada.
Institute of Hematology and Blood Transfusion, Prague, Czech Republic.
Int Arch Allergy Immunol. 2018;177(2):145-152. doi: 10.1159/000489706. Epub 2018 Jun 26.
Atopy is defined as excess allergen-specific IgE (A-IgE). IgE is produced by plasma cells that differentiate from allergen-specific B cells. B cells are known to be killed by chemotherapy; however, it is not known whether A-IgE-secreting plasma cells are killed or inhibited by chemotherapy. If yes, serum A-IgE levels would be expected to decrease after chemotherapy.
We aimed to determine whether A-IgE levels in atopic individuals (serum A-IgE ≥0.35 kUA/L) decrease into the nonatopic range (< 0.35 kUA/L) after chemotherapy.
In 105 patients undergoing chemotherapy for acute leukemia, we measured serum A-IgE before and after chemotherapy. In a subset of these patients, we also measured B cell counts before and after chemotherapy.
Of the 105 patients, 36 were atopic. In these patients, median A-IgE level before chemotherapy was 1.6 kUA/L whereas the median level after chemotherapy was 0.6 kUA/L (p < 0.001). In 12/36 (33%) patients, A-IgE levels decreased into the nonatopic range. In nonatopic patients (n = 69), the median A-IgE level also dropped: from 0.04 kUA/L before to 0.03 kUA/L after chemotherapy (p = 0.001). Among the total patients (n = 105), the median pre:post-chemotherapy A-IgE ratio was 1.8 (2.6 in atopic and 1.5 in nonatopic patients). In contrast, the median ratio of pre:post-chemotherapy B cell counts was 87.6.
A-IgE levels decrease after chemotherapy but markedly less than B cell counts. Thus, at least some A-IgE plasma cells appear to survive chemotherapy.
特应性被定义为过量的过敏原特异性IgE（A-IgE）。IgE由从过敏原特异性B细胞分化而来的浆细胞产生。已知B细胞会被化疗杀死；然而，尚不清楚分泌A-IgE的浆细胞是否会被化疗杀死或抑制。如果是这样，化疗后血清A-IgE水平预计会下降。
我们旨在确定特应性个体（血清A-IgE≥0.35 kUA/L）化疗后A-IgE水平是否会降至非特应性范围（<0.35 kUA/L）。
在105例接受急性白血病化疗的患者中，我们测量了化疗前后的血清A-IgE。在这些患者的一个亚组中，我们还测量了化疗前后的B细胞计数。
105例患者中，36例为特应性。在这些患者中，化疗前A-IgE水平中位数为1.6 kUA/L，而化疗后中位数水平为0.6 kUA/L（p<0.001）。在12/36（33%）的患者中，A-IgE水平降至非特应性范围。在非特应性患者（n = 69）中，A-IgE水平中位数也下降：从化疗前的0.04 kUA/L降至化疗后的0.03 kUA/L（p = 0.001）。在全部患者（n = 105）中，化疗前与化疗后A-IgE比值中位数为1.8（特应性患者为2.6，非特应性患者为1.5）。相比之下，化疗前与化疗后B细胞计数比值中位数为87.6。
化疗后A-IgE水平下降，但明显低于B细胞计数。因此，至少一些分泌A-IgE的浆细胞似乎能在化疗中存活。
