Related Experiment Videos
Natural killer cell-mediated lysis of autologous cells modified by gene therapy
C Liberatore1, M Capanni, N Albi
1Division of Internal Medicine and Oncological Sciences, Department of Clinical and Experimental Medicine, University of Perugia, 06100 Perugia, Italy.
Abstract:
This study investigated the role of natural killer (NK) cells as effectors of an immune response against autologous cells modified by gene therapy. T lymphocytes were transduced with LXSN, a retroviral vector adopted for human gene therapy that carries the selectable marker gene neo, and the autologous NK response was evaluated. We found that (i) infection with LXSN makes cells susceptible to autologous NK cell-mediated lysis; (ii) expression of the neo gene is responsible for conferring susceptibility to lysis; (iii) lysis of neo-expressing cells is clonally distributed and mediated only by NK clones that exhibit human histocompatibility leukocyte antigen (HLA)-Bw4 specificity and bear KIR3DL1, a Bw4-specific NK inhibitory receptor; and (iv) the targets are cells from HLA-Bw4(+) individuals. Finally, neo peptides anchoring to the Bw4 allele HLA-B27 interfered with KIR3DL1-mediated recognition of HLA-B27, i.e., they triggered NK lysis. Moreover, neo gene mutations preventing translation of two of the four potentially nonprotective peptides reduced KIR3DL1(+) NK clone-mediated autologous lysis. Thus, individuals expressing Bw4 alleles possess an NK repertoire with the potential to eliminate autologous cells modified by gene therapy. By demonstrating that NK cells can selectively detect the expression of heterologous genes, these observations provide a general model of the NK cell-mediated control of viral infections.
Insights
Gene therapy using LXSN vectors makes cells vulnerable to natural killer (NK) cell attacks. Specific NK cell receptors targeting neo gene peptides trigger lysis of modified autologous cells.
Area of Science:
- Immunology
- Gene Therapy
- Cell Biology
Background:
- Natural killer (NK) cells are crucial for innate immunity.
- Gene therapy aims to modify cells for therapeutic purposes.
- Understanding immune responses to gene-modified cells is vital for safety.
Purpose of the Study:
- To investigate the role of NK cells in eliminating autologous cells modified by gene therapy.
- To determine the specific mechanisms by which NK cells recognize and lyse gene-modified cells.
- To explore the potential of NK cells as a safety mechanism in gene therapy.
Main Methods:
- Transduction of T lymphocytes with the LXSN retroviral vector.
- Evaluation of autologous NK cell responses against gene-modified cells.
- Analysis of NK cell receptor specificity (KIR3DL1) and target cell recognition (HLA-Bw4).
- Investigation of neo gene peptide interactions with HLA alleles.
Main Results:
- LXSN vector transduction confers susceptibility to autologous NK cell-mediated lysis.
- The neo gene's expression is directly responsible for this susceptibility.
- NK cell-mediated lysis is specific to NK clones recognizing HLA-Bw4 and is mediated by KIR3DL1.
- Neo peptides binding to HLA-Bw4 alleles can trigger NK cell lysis, even interfering with inhibitory receptor function.
Conclusions:
- Autologous NK cells, particularly those with HLA-Bw4 specificity, can eliminate gene therapy-modified cells.
- The neo gene product acts as a target for specific NK cell recognition.
- This study provides a model for NK cell-mediated control of viral infections and highlights a potential safety mechanism in gene therapy.