Rahman Eqram, Rao Parinitha, Ahmed Munim, Webb William Richard, Carruthers Jean D A
Research and Innovation Hub, Innovation Aesthetics, London WC2H 9JQ, UK.
The Skin Address, Bengaluru 560080, India.
Toxins (Basel). 2025 Apr 6;17(4):182. doi: 10.3390/toxins17040182.
Botulinum toxin A (BoNT-A) is widely used in both therapeutic and aesthetic settings; however, the formation of neutralizing antibodies (NAbs) remains a critical concern, leading to treatment failure. Immunogenic responses are known to vary between individuals due to HLA polymorphisms. Although some claim that neurotoxin-associated proteins (NAPs) shield BoNT-A from immune detection or are themselves immunogenic, there is limited molecular evidence supporting either view. This study applies computational immunogenetics to explore BoNT-A immunogenicity, focusing on HLA binding and the influence of accessory proteins. Epitope mapping, molecular docking, and HLA binding predictions were used to evaluate interactions between BoNT-A epitopes and selected class II HLA alleles (HLA-DQA101:02, HLA-DQA103:03, HLA-DQB106:04, HLA-DQB103:01, and HLA-DRB115:01). To assess the potential immunomodulatory role of NAPs, molecular dynamics (MD) simulations, solvent-accessible surface area (SASA) analysis, and electrostatic potential mapping were also conducted. Key epitopes-L11, N25, and C10-showed strong binding affinities to HLA-DQA101:02, HLA-DQB106:04, and HLA-DQA103:03, indicating a potential immunodominant role. NAPs did not obstruct these epitopes but slightly increased their exposure and appeared to stabilize the toxin structure. Electrostatic mapping and binding free energy calculations suggested no significant immunogenic shift in the presence of NAPs. BoNT-A immunogenicity appears to be influenced by HLA allele variability, reinforcing the value of patient-specific genetic profiling. The presumed immunogenic role of NAPs remains unsubstantiated at the molecular level, underscoring the need for evidence-based evaluation over commercial rhetoric. While these findings provide valuable molecular insight, it is important to acknowledge that they are derived entirely from in silico analyses. As such, experimental validation remains essential to confirm the immunological relevance of these predicted interactions. Nonetheless, this computational framework offers a rational basis for guiding future clinical research and the development of HLA-informed BoNT-A therapies.
A型肉毒杆菌毒素（BoNT-A）广泛应用于治疗和美容领域；然而，中和抗体（NAbs）的形成仍然是一个关键问题，可导致治疗失败。已知由于HLA多态性，个体之间的免疫原性反应存在差异。尽管有人声称神经毒素相关蛋白（NAPs）可保护BoNT-A不被免疫检测到，或者其本身具有免疫原性，但支持这两种观点的分子证据都很有限。本研究应用计算免疫遗传学来探索BoNT-A的免疫原性，重点关注HLA结合以及辅助蛋白的影响。采用表位作图、分子对接和HLA结合预测来评估BoNT-A表位与选定的II类HLA等位基因（HLA-DQA101:02、HLA-DQA103:03、HLA-DQB106:04、HLA-DQB103:01和HLA-DRB115:01）之间的相互作用。为了评估NAPs的潜在免疫调节作用，还进行了分子动力学（MD）模拟、溶剂可及表面积（SASA）分析和静电势图谱分析。关键表位-L11、N25和C10-显示出与HLA-DQA101:02、HLA-DQB106:04和HLA-DQA103:03有很强的结合亲和力，表明其可能具有免疫显性作用。NAPs没有阻碍这些表位，但略微增加了它们的暴露程度，并且似乎稳定了毒素结构。静电图谱和结合自由能计算表明，在存在NAPs的情况下没有明显的免疫原性变化。BoNT-A的免疫原性似乎受HLA等位基因变异性的影响，这强化了患者特异性基因分析的价值。NAPs假定的免疫原性作用在分子水平上仍未得到证实，这突出了基于证据的评估而非商业说辞的必要性。虽然这些发现提供了有价值的分子见解，但必须承认它们完全来自于计算机分析。因此，实验验证对于确认这些预测相互作用的免疫学相关性仍然至关重要。尽管如此，这个计算框架为指导未来的临床研究和开发基于HLA的BoNT-A疗法提供了合理的基础。
