Department of Hematology, Graduate School of Medicine, Osaka City University, Japan.
Department of Parasitology & Research Center for Infectious Disease Sciences, Graduate School of Medicine, Osaka City University, Japan.
Intern Med. 2021;60(23):3827-3831. doi: 10.2169/internalmedicine.7884-21. Epub 2021 Dec 1.
A 73-year-old man previously treated with rituximab for his mucosa-associated lymphoid tissue lymphoma suffered a suboptimal humoral immune response against an acquired SARS-CoV-2 infection. A detailed serological description revealed discrepant antigen-specific humoral immune responses. The titer of spike-targeting, "viral-neutralizing" antibodies remained below the detection level, in contrast to the anti-nucleocapsid, "binding" antibody response, which was comparable in both magnitude and kinetics. Accordingly, viral neutralizability and clearance was delayed, leading to prolonged RNAemia and persistent pneumonia. The present case highlights the need to closely monitor this unique population of recipients of B-cell-targeted therapies for their neutralizing antibody responses against SARS-CoV-2.
一位 73 岁的男性曾因黏膜相关淋巴组织淋巴瘤接受利妥昔单抗治疗，此次感染 SARS-CoV-2 后出现体液免疫应答不佳的情况。详细的血清学描述显示出不一致的抗原特异性体液免疫应答。针对刺突蛋白的抗体滴度，即“病毒中和”抗体仍低于检测水平，而针对核衣壳的抗体应答，即“结合”抗体，在幅度和动力学上都相当。因此，病毒的中和能力和清除能力被延迟，导致 RNA 血症持续时间延长和持续性肺炎。本病例强调了需要密切监测接受 B 细胞靶向治疗的这一独特人群对 SARS-CoV-2 的中和抗体反应。
