Division of Hematology, Department of Medicine, Keio University School of Medicine, Tokyo, Japan.
Division of Hematology, Department of Medicine, Keio University School of Medicine, Tokyo, Japan; Center for Transfusion Medicine and Cell Therapy, Keio University School of Medicine, Tokyo, Japan.
Transplant Cell Ther. 2021 Feb;27(2):174.e1-174.e5. doi: 10.1016/j.jtct.2020.10.011. Epub 2020 Dec 11.
The majority of adults are seropositive for human herpesvirus 6 (HHV-6). HHV-6 reactivation can occur after allogeneic hematopoietic stem cell transplantation (HSCT) and lead to life-threatening central nervous system disorders. In this prospective study, we evaluated the relationship between HHV-6 reactivation and anti-HHV-6 IgG antibody levels in recipients of allogeneic HSCT. The HHV-6 viral load in the plasma was quantitatively measured weekly after allogeneic HSCT by real-time polymerase chain reaction. The level of anti-HHV-6 IgG antibody was measured by enzyme-linked immunosorbent assay before and serially after transplantation. In 28 of the 56 evaluated patients (50%), HHV-6 reactivation was detected after transplantation. In a multivariate analysis, cord blood as the stem cell source was the only significant factor associated with HHV-6 reactivation (odds ratio, 8.6; 95% confidence interval, 2.3 to 32.6; P < .01). When evaluated in the recipients of cord blood transplantation (CBT), the anti-HHV-6 antibody level before transplantation was significantly lower in the patients with HHV-6 reactivation compared with those without (sample positivity index: median, 2.04 [range, 0.95 to 5.98] versus 4.15 [range, 3.93 to 5.65]; P < .05). The anti-HHV-6 antibody level was significantly decreased at 3 months post-transplantation compared with before transplantation (P < .01). Such differences were not observed in other stem cell sources. Our results demonstrate that the low anti-HHV-6 antibody level before transplantation was associated with the reactivation of HHV-6 after CBT, and that the anti-HHV-6 antibody level was significantly decreased specifically after CBT. These results suggest that HHV-6-specific humoral immunity plays a role in HHV-6 reactivation after CBT.
大多数成年人的血清均为人类疱疹病毒 6（HHV-6）阳性。异基因造血干细胞移植（HSCT）后，HHV-6 可能会重新激活，并导致危及生命的中枢神经系统疾病。在这项前瞻性研究中，我们评估了异基因 HSCT 受者 HHV-6 再激活与抗 HHV-6 IgG 抗体水平之间的关系。异基因 HSCT 后每周通过实时聚合酶链反应定量测量血浆中的 HHV-6 病毒载量。移植前后通过酶联免疫吸附试验连续测量抗 HHV-6 IgG 抗体水平。在评估的 56 例患者中有 28 例（50%）在移植后检测到 HHV-6 再激活。在多变量分析中，以脐带血作为干细胞来源是与 HHV-6 再激活相关的唯一显著因素（比值比，8.6；95%置信区间，2.3 至 32.6；P <.01）。在脐带血移植（CBT）受者中评估时，与未发生 HHV-6 再激活的患者相比，发生 HHV-6 再激活的患者移植前的抗 HHV-6 抗体水平显著较低（样本阳性指数：中位数，2.04 [范围，0.95 至 5.98] 与 4.15 [范围，3.93 至 5.65]；P <.05）。与移植前相比，移植后 3 个月时的抗 HHV-6 抗体水平显著降低（P <.01）。在其他干细胞来源中未观察到这种差异。我们的研究结果表明，移植前的低抗 HHV-6 抗体水平与 CBT 后 HHV-6 的重新激活有关，并且 CBT 后抗 HHV-6 抗体水平显著降低。这些结果表明，HHV-6 特异性体液免疫在 CBT 后 HHV-6 再激活中起作用。
