Max-Delbrück Centrum für Molekulare Medizin, Berlin-Buch, Berlin.
Circ J. 2012;76(10):2449-55. doi: 10.1253/circj.cj-12-0212. Epub 2012 Jul 27.
Application of immunoapheresis to eliminate pathogenic autoantibodies targeting the second extracellular loop of the β1-receptor (β1-AABs) is currently investigated in patients with cardiomyopathy. Aptamers (single short DNA or RNA strands) are a new class of molecules that bind to a specific target molecule. This property qualifies aptamers for potential use in the apheresis technique. We recently identified an aptamer that specifically binds to β1-AABs, so in the present study we tested whether this aptamer could be used as a binder to prepare an apheresis column suitable for clearing β1-AABs from rat's blood.
An apheresis column was designed containing the β1-AAB-targeting-aptamer coupled to sepharose. As tested in vitro, this column (1) binds β1-AABs highly specifically without marked interference with common IgGs, (2) has a capacity for clearing of approximately 1L of β1-AAB-positive serum and (3) can be completely regenerated for subsequent use. Using the column for extracorporeal apheresis of spontaneously hypertensive rats (SHR) positive for both β1-AABs and muscarinic 2-receptor autoantibodies (M2-AABs), only β1-AABs were removed. In a follow-up of 9 weeks, recurrence of β1-AABs in the blood of SHR could not be detected.
For the first time, a newly designed apheresis column with a β1-AAB specific aptamer as a binder was successfully used to eliminate β1-AABs from SHR blood.
免疫亲和吸附法目前应用于消除针对β1 受体第二细胞外环的致病性自身抗体（β1-AABs），以治疗心肌病患者。适体（单链短 DNA 或 RNA）是一种新型分子，可与特定靶分子结合。这种特性使适体有资格成为亲和吸附技术的潜在用途。我们最近鉴定了一种特异性结合β1-AAB 的适体，因此在本研究中，我们测试了这种适体是否可以作为结合物，制备亲和吸附柱，用于从大鼠血液中清除β1-AAB。
设计了一种亲和吸附柱，其中含有与琼脂糖偶联的针对β1-AAB 的适体。如体外测试所示，该柱（1）高度特异性结合β1-AAB，而不会对常见 IgG 产生明显干扰，（2）可清除约 1L 含β1-AAB 的阳性血清，（3）可完全再生，以备后续使用。使用该柱对自发性高血压大鼠（SHR）进行体外亲和吸附，这些 SHR 同时存在β1-AAB 和毒蕈碱 2 受体自身抗体（M2-AAB）。结果仅清除了β1-AAB。在 9 周的随访中，未检测到 SHR 血液中β1-AAB 的复发。
首次成功使用一种新设计的亲和吸附柱，其中含有β1-AAB 特异性适体作为结合物，从 SHR 血液中清除了β1-AAB。
