Allogeneic hematopoietic stem cell transplantation (HSCT) is the effective mean of immune restoration in severe combined immunodefiency (SCID). Usually, HSCT without cytoreductive conditioning is attempted. Nevertheless, conditioning procedures are still preferred in a subset of patients. Herein, we describe the immunological outcome in a cohort of conditioned and unconditioned patients, from diagnosis, through transplantation, to follow-up. This retrospective study was conducted on 17 patients with SCID (10 conditioned, 7 unconditioned) who later underwent HSCT. Immune reconstitution was assessed in the post-transplant year by quantification of T cell receptor excision circles (TRECs) and kappa-deleting recombination excision circles (KRECs), among additional laboratory and clinical evaluations. Unconditioned patients were diagnosed and transplanted earlier. TREC and KREC quantification showed a gradual increase in both groups, with higher levels in the conditioned group. Engraftment percentages differed drastically between groups, favoring the conditioned group. Unconditioned patients were significantly more dependent on intravenous immunoglobulins (IVIGs). One patient from each group succumbed to disease complications. Conditioning demonstrated superior laboratorial outcomes. Patients with unique characteristics (i.e., consanguinity, Bacillus Calmette-Guérin vaccination, impaired access to IVIG) may require personalized considerations. The effort to implement secondary prevention of SCID with newborn screening should continue.

中文翻译：

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在有条件和无条件患者的SCID中进行HSCT后的免疫重建。

异基因造血干细胞移植（HSCT）是严重的联合免疫缺陷症（SCID）中免疫恢复的有效手段。通常，尝试不进行细胞还原性调节的HSCT。尽管如此，在部分患者中仍首选调理程序。本文中，我们描述了从诊断，移植到随访的一组条件和非条件患者的免疫学结果。这项回顾性研究针对17例SCID患者（10例条件性，7例非条件性）随后接受了HSCT。在移植后的一年中，通过对T细胞受体切除环（TRECs）和Kappa缺失重组切除环（KRECs）进行定量评估，以及其他实验室和临床评估来评估免疫重建。未患病的患者被诊断出并较早移植。TREC和KREC定量显示两组均逐渐升高，而条件治疗组水平更高。各组之间的植入率差异很大，有利于条件正常的组。无条件的患者明显更多地依赖于静脉内免疫球蛋白（IVIG）。每一组中的一名患者死于疾病并发症。调理显示出优越的实验室效果。具有独特特征（即血缘，卡尔梅特芽孢杆菌-Guérin疫苗接种，IVIG通路障碍）的患者可能需要个性化考虑。应当继续努力通过新生儿筛查实施SCID的二级预防。在适应组中水平较高。各组之间的植入率差异很大，有利于条件正常的组。无条件的患者明显更多地依赖于静脉内免疫球蛋白（IVIG）。每一组中的一名患者死于疾病并发症。调理显示出优越的实验室效果。具有独特特征（即血缘，卡尔梅特芽孢杆菌-Guérin疫苗接种，IVIG通路障碍）的患者可能需要个性化考虑。应当继续努力通过新生儿筛查实施SCID的二级预防。在适应组中水平较高。各组之间的植入率差异很大，有利于条件正常的组。无条件的患者明显更多地依赖于静脉内免疫球蛋白（IVIG）。每一组中的一名患者死于疾病并发症。调理显示出优越的实验室效果。具有独特特征（即血缘，卡尔梅特芽孢杆菌-Guérin疫苗接种，IVIG通路障碍）的患者可能需要个性化考虑。应当继续努力通过新生儿筛查实施SCID的二级预防。每一组中的一名患者死于疾病并发症。调理显示出优越的实验室效果。具有独特特征（即血缘，卡尔梅特芽孢杆菌-Guérin疫苗接种，IVIG通路障碍）的患者可能需要个性化考虑。应当继续努力通过新生儿筛查实施SCID的二级预防。每一组中的一名患者死于疾病并发症。调理显示出优越的实验室效果。具有独特特征（即血缘，卡尔梅特芽孢杆菌-Guérin疫苗接种，IVIG通路障碍）的患者可能需要个性化考虑。应当继续努力通过新生儿筛查实施SCID的二级预防。