血小板裂解物对耐甲氧西林金黄色葡萄球菌 生物膜的抑制作用及对PIA合成的影响

Inhibitory Effect of Platelet Lysate on Methicillin-Resistant Staphylococcus aureus Biofilm and Its Impact on PIA Synthesis

摘要: 目的：探究血小板裂解物(Platelet Lysate, PL)对耐甲氧西林金黄色葡萄球菌(Methicillin-Resistant Staphylococcus aureus, MRSA)生物膜形成的影响及其作用机制。方法：采用微量肉汤稀释法测定PL对MRSA浮游菌的最小抑菌浓度(MIC)；通过结晶紫染色评估PL对生物膜形成及成熟生物膜的干预作用；利用刚果红平板法检测PL对多糖胞间黏附素(PIA)生成的影响；通过扫描电镜观察MRSA生物膜的结构变化。结果：PL在实验浓度范围内未显示对浮游菌的MIC。结晶紫染色表明，PL可浓度依赖性地显著抑制MRSA生物膜形成(P < 0.05)，但对成熟生物膜无显著影响。刚果红实验显示PL不抑制PIA生成。扫描电镜观察证实PL能破坏生物膜的三维结构，使其变得稀疏、不连续。结论：PL在非杀菌浓度下可有效抑制MRSA生物膜形成并破坏其结构，且该作用可能不依赖于PIA合成通路，提示PL可能通过干扰细菌初始黏附等非经典途径发挥抗生物膜效应，为基于血小板来源制剂的抗生物膜策略提供了实验依据。

Abstract: Objective: To investigate the effect of platelet lysate (Platelet Lysate, PL) on the formation of methicillin-resistant Staphylococcus aureus (Methicillin-Resistant Staphylococcus aureus, MRSA) biofilms and its underlying mechanism. Methods: The minimum inhibitory concentration (MIC) of PL against MRSA planktonic bacteria was determined using the microdilution broth method. The inhibitory effect of PL on biofilm formation and mature biofilms was evaluated by crystal violet staining. The Congo red plate assay was used to assess the impact of PL on polysaccharide intercellular adhesin (PIA) production. Structural changes in MRSA biofilms were observed by scanning electron microscopy. Results: PL did not exhibit a MIC against planktonic bacteria within the experimental concentration range. Crystal violet staining indicated that PL significantly inhibited MRSA biofilm formation in a concentration-dependent manner (P < 0.05), but had no significant effect on mature biofilms. The Congo red assay showed that PL did not inhibit PIA production. Scanning electron microscopy confirmed that PL disrupted the three-dimensional architecture of biofilms, rendering them sparse and discontinuous. Conclusion: At non-bactericidal concentrations, PL effectively inhibits MRSA biofilm formation and disrupts biofilm structure. This effect may not be dependent on the PIA synthesis pathway, suggesting that PL may exert its anti-biofilm effects through non-classical pathways, such as interfering with initial bacterial adhesion. This study provides experimental evidence for platelet-derived products as a potential anti-biofilm strategy.