Gokmen E, Bachier C, Raaphorst F M, Muller T, Armstrong D, LeMaistre C F, Teale J M
The University of Texas Health Science Center, San Antonio, TX 78229-3900, USA.
Bone Marrow Transplant. 2001 Feb;27(4):413-24. doi: 10.1038/sj.bmt.1702794.
It is largely unknown whether the immune repertoire can be reconstituted successfully after high-dose chemotherapy and transplantation using ex vivo expanded hematopoietic stem cell (HSC) grafts. It is critically important for the transplant outcome that immune repertoire reconstitution progresses after ex vivo expanded HSC graft transplants at least as efficiently as that seen after conventional HSC transplants. Previously, we showed that the T cell receptor V beta (TCRVB) third complementarity determining region (CDR3) diversification after ex vivo expanded bone marrow (BM) HSC graft transplants was similar to that seen after conventional peripheral blood stem cell transplants (PBSCTs). In the present study, the CDR3 diversity of the six immunoglobulin (Ig) heavy chain variable region gene (V(H)) families was examined in five breast cancer patients who were transplanted with ex vivo expanded BM HSCs as the only source of stem cells. For comparison, 12 healthy adults and four conventional PBSCT recipients were also studied. Using both CDR3 fingerprinting and single strand conformation polymorphism (SSCP) methodologies, it is shown that the contribution of the V(H) families to the overall repertoire among healthy adults is highly variable and not always proportional to V(H) family member size. After both ex vivo expanded HSC transplants and conventional PBSCTs, the V(H) CDR3 repertoires were limited in size diversity at 6 weeks post transplant. By 6 months, however, V(H) families displayed a repertoire diversity that was as complex as that seen in healthy adults. No difference was seen between ex vivo expanded HSC graft transplant recipients and conventional PBSCT recipients in V(H) repertoire diversity. In one patient there was a follow-up analysis 12 months after ex vivo expanded graft transplant, and the diversity of the V(H) families was maintained. In all patients, the amino acid size of the CDR3 regions fell within adult limits at all time points post transplant. These results indicate that B cell repertoire regeneration after ex vivo expanded hematopoietic cell graft transplants is similar to that seen after conventional PBSCT.
大剂量化疗及使用体外扩增造血干细胞（HSC）移植物进行移植后，免疫库能否成功重建在很大程度上尚不清楚。对于移植结果而言，至关重要的是体外扩增HSC移植物移植后免疫库重建的进展至少要与传统HSC移植后的效率相当。此前，我们发现体外扩增骨髓（BM）HSC移植物移植后T细胞受体Vβ（TCRVB）第三个互补决定区（CDR3）的多样化与传统外周血干细胞移植（PBSCT）后的情况相似。在本研究中，对5例仅接受体外扩增BM HSC作为唯一干细胞来源移植的乳腺癌患者，检测了6个免疫球蛋白（Ig）重链可变区基因（V(H)）家族的CDR3多样性。作为对照，还研究了12名健康成年人及4例接受传统PBSCT的患者。使用CDR3指纹图谱和单链构象多态性（SSCP）方法，结果显示健康成年人中V(H)家族对总体免疫库的贡献差异很大，且并不总是与V(H)家族成员数量成正比。体外扩增HSC移植和传统PBSCT后，移植后6周时V(H) CDR3免疫库的大小多样性均有限。然而，到6个月时，V(H)家族的免疫库多样性已与健康成年人中的情况一样复杂。体外扩增HSC移植物移植受者与传统PBSCT受者在V(H)免疫库多样性方面未见差异。对1例患者在体外扩增移植物移植后12个月进行了随访分析，V(H)家族的多样性得以维持。在所有患者中，移植后所有时间点CDR3区域的氨基酸大小均在成年人正常范围内。这些结果表明，体外扩增造血细胞移植物移植后B细胞免疫库的再生与传统PBSCT后的情况相似。
