Division of Hematopathology, Dalhousie University, Halifax, Nova Scotia, Canada.
Hematology Division, Brigham and Women's Hospital, Boston, Massachusetts.
Transfusion. 2019 May;59(5):1644-1647. doi: 10.1111/trf.15192. Epub 2019 Feb 12.
We recently discovered that 30% of current frequent apheresis platelet donors in a study at our donor center had CD4+ counts below 200 cells/μL. How long CD4+ lymphopenia persists after ceasing plateletpheresis is unknown. Whether there are infectious or other complications in former frequent donors that could relate to CD4+ lymphopenia is also unknown.
We mailed a letter to former frequent apheresis platelet donors who had not donated platelets for at least 12 months. Frequent donation was defined as 20 to 24 plateletpheresis sessions in at least one 365-day period starting in 2011. Donors who expressed interest in the study were contacted to schedule a study visit. Participants in the study provided a blood sample and completed a health questionnaire that included questions about opportunistic infections and malignancies.
Of 50 potential study candidates who were mailed a letter, 15 participated in the study. There were 2 participants with CD4+ counts below 200 cells/μL, one of whom had prior counts that documented a small improvement with cessation of plateletpheresis. Three participants had counts between 200 and 300 cells/μL. No study participant had a history of an opportunistic infection or a malignancy associated with immune dysregulation.
We detected CD4+ lymphopenia in former frequent apheresis platelet donors who had ceased platelet donation for more than 1 year. There was no evidence that the CD4+ lymphopenia predisposes to opportunistic infections or to malignancies associated with immune dysregulation.
我们最近发现,在我们的献血中心进行的一项研究中,目前经常进行血小板单采术的献血者中有 30%的 CD4+计数低于 200 个细胞/μL。停止血小板单采术后 CD4+淋巴细胞减少持续多长时间尚不清楚。以前的频繁献血者中是否存在与 CD4+淋巴细胞减少相关的感染或其他并发症也不清楚。
我们向至少 12 个月未捐献血小板的前频繁血小板单采术献血者邮寄了一封信。频繁献血定义为自 2011 年开始的至少 365 天内进行 20-24 次血小板单采术。对研究感兴趣的献血者进行联系以安排研究访问。研究参与者提供了一份血样,并完成了一份健康问卷,其中包括关于机会性感染和恶性肿瘤的问题。
在寄出信的 50 名潜在研究候选人中,有 15 人参加了研究。有 2 名参与者的 CD4+计数低于 200 个细胞/μL,其中 1 名参与者的计数在停止血小板单采术后有小幅改善。3 名参与者的计数在 200-300 个细胞/μL 之间。没有研究参与者有机会性感染或与免疫失调相关的恶性肿瘤病史。
我们在停止血小板捐献超过 1 年的前频繁血小板单采术献血者中检测到 CD4+淋巴细胞减少。没有证据表明 CD4+淋巴细胞减少易发生机会性感染或与免疫失调相关的恶性肿瘤。