Caballero Pamela Scaraffuni, Pereira Isabel Ladeira, de Freitas Stella Buchhorn, Neis Alessandra, Cardoso Thayná Laner, Wozeak Daniela Rodriguero, Neto Amilton Clair Pinto Seixas, da Silva Pinto Luciano, Hartwig Daiane Drawanz
Biotechnology Unit, Center of Technological Development, Federal University of Pelotas, Pelotas, RS, CEP 96010-900, Brazil.
Department of Microbiology and Parasitology, Biology Institute, Federal University of Pelotas, Pelotas, RS, CEP 96010-900, Brazil.
Braz J Microbiol. 2025 Jun;56(2):893-904. doi: 10.1007/s42770-025-01666-1. Epub 2025 Apr 24.
This study aimed to develop a multi-epitope recombinant chimera (rChimera) based on two outer membrane proteins of Acinetobacter baumannii, targeting passive or active immunization strategies against biofilm-forming strains of this multidrug-resistant bacterium. Using bioinformatics and reverse vaccinology, we identified CAM87009.1 and FilF as two conserved proteins involved in biofilm formation and host cell adherence. An in silico analysis was performed to design the rChimera, selecting 36 promising B- and T-cell epitopes, including those recognized by MHC class I and II. These epitopes were linked using a glycine linker (GGGG) and a rigid linker (EAAKEAAAKA). The chimera was chemically synthesized, successfully expressed in Escherichia coli BL21 Star, and recognized by antibodies from naturally infected patients. Polyclonal antibodies (pAbs) produced in a murine model elicited a significant IgG response from the 14th day after the first immunization, with IgG1 and IgG2 (a and b) being the predominant isotypes generated. Anti-rChimera pAbs effectively inhibited biofilm formation in multidrug-resistant isolates and the ATCC® 19,606 strain of A. baumannii. The recombinant chimera shows promise for passive or active immunization against biofilm-forming strains of A. baumannii.
本研究旨在基于鲍曼不动杆菌的两种外膜蛋白开发一种多表位重组嵌合体（rChimera），针对这种多重耐药细菌的生物膜形成菌株采用被动或主动免疫策略。利用生物信息学和反向疫苗学，我们鉴定出CAM87009.1和FilF为参与生物膜形成和宿主细胞黏附的两种保守蛋白。进行了计算机模拟分析以设计rChimera，选择了36个有前景的B细胞和T细胞表位，包括那些被MHC I类和II类识别的表位。这些表位通过甘氨酸接头（GGGG）和刚性接头（EAAKEAAAKA）连接。该嵌合体经化学合成，在大肠杆菌BL21 Star中成功表达，并被自然感染患者的抗体识别。在小鼠模型中产生的多克隆抗体（pAbs）在首次免疫后第14天引发了显著的IgG反应，其中IgG1和IgG2（a和b）是产生的主要亚型。抗rChimera pAbs有效抑制了多重耐药菌株和鲍曼不动杆菌ATCC® 19,606菌株中的生物膜形成。该重组嵌合体显示出针对鲍曼不动杆菌生物膜形成菌株进行被动或主动免疫的潜力。
