Trifonova Daria, Curin Mirela, Focke-Tejkl Margarete, Liu Zicheng, Borochova Kristina, Gattinger Pia, van Hage Marianne, Grönlund Hans, Kiss Renata, Huang Huey-Jy, Keller Walter, Riabova Ksenja, Karsonova Antonina, Kundi Michael, Tulaeva Inna, Fomina Daria, Karaulov Alexander, Valenta Rudolf
Department of Pathophysiology and Allergy Research, Division of Immunopathology, Center for Pathophysiology, Infectiology, and Immunology, Medical University of Vienna, Vienna, Austria.
LIFE Improvement by Future Technologies (LIFT) Center, Skolkovo, Moscow, Russia.
Allergy. 2025 Apr 3. doi: 10.1111/all.16542.
Molecular forms of allergen-specific immunotherapy (AIT) for cat allergy are needed. Fel d 1, Fel d 4, and Fel d 7 are the most important cat allergens.
IgE epitopes of Fel d 4 and Fel d 7 were mapped by blocking allergic patients' IgE binding with allergen peptide-specific antisera. Five recombinant fusion proteins (PreS-Cat 1-PreS-Cat 5) each containing hepatitis B virus (HBV)-derived PreS as an immunological carrier and non-allergenic peptides from the IgE binding sites of Fel d 1, Fel d 4, and Fel d 7 were expressed in Escherichia coli, purified, and characterized by mass spectrometry, circular dichroism (CD), and size exclusion chromatography. ImmunoCAP and basophil activation experiments demonstrated the hypoallergenic activity of PreS-Cat 1-5. The ability of PreS-Cat 1-5 to induce IgE-blocking antibodies in rabbits was compared to three licensed allergen extract-based AIT vaccines. PreS-Cat 1-5-specific IgG antibodies were tested for inhibition of allergen-specific IgE binding and specific basophil activation. T cell activation and induction of specific cytokine secretion by PreS-Cat proteins were compared with cat allergens in PBMC cultures.
Recombinant hypoallergenic, biochemically and structurally defined PreS-Cat 1-5 were obtained. Two subcutaneous immunizations of rabbits with PreS-Cat 1-5 induced equal (Fel d 1) or better (Fel d 4 and Fel d 7) antibodies (PreS-Cat 5 > PreS-Cat 1 > PreS-Cat 3) blocking allergic patients' IgE binding to cat allergens than six to fifteen immunizations with allergen extract-based vaccines. PreS-Cat-specific antibodies strongly inhibited specific basophil activation. PreS-Cat 5 > PreS-Cat 1 induced significantly more IL-10 in cultured PBMCs from cat allergic patients than cat allergens.
PreS-Cat 5 and PreS-Cat 1 are highly promising molecular vaccine candidates for AIT of cat allergy, combining Fel d 1-, Fel d 4-, and Fel d 7-peptides in single PreS fusion proteins.
需要用于猫过敏的变应原特异性免疫疗法（AIT）的分子形式。猫主要变应原Fel d 1、Fel d 4和Fel d 7。
通过用变应原肽特异性抗血清阻断过敏患者的IgE结合来绘制Fel d 4和Fel d 7的IgE表位。五种重组融合蛋白（PreS-Cat 1-PreS-Cat 5），每种均包含源自乙型肝炎病毒（HBV）的PreS作为免疫载体以及来自Fel d 1、Fel d 4和Fel d 7的IgE结合位点的非变应原性肽，在大肠杆菌中表达、纯化，并通过质谱、圆二色性（CD）和尺寸排阻色谱进行表征。免疫捕获和嗜碱性粒细胞活化实验证明了PreS-Cat 1-5的低变应原活性。将PreS-Cat 1-5在兔中诱导IgE阻断抗体的能力与三种基于变应原提取物的已获许可的AIT疫苗进行比较。测试PreS-Cat 1-5特异性IgG抗体对变应原特异性IgE结合和特异性嗜碱性粒细胞活化的抑制作用。在PBMC培养物中，将PreS-Cat蛋白诱导的T细胞活化和特异性细胞因子分泌与猫变应原进行比较。
获得了重组低变应原性、生化和结构明确的PreS-Cat 1-5。用PreS-Cat 1-5对兔进行两次皮下免疫诱导出的阻断过敏患者IgE与猫变应原结合的抗体，与基于变应原提取物的疫苗进行六至十五次免疫诱导出的抗体相当（Fel d 1）或更好（Fel d 4和Fel d 7）（PreS-Cat 5＞PreS-Cat 1＞PreS-Cat 3）。PreS-Cat特异性抗体强烈抑制特异性嗜碱性粒细胞活化。PreS-Cat 5＞PreS-Cat 1在猫过敏患者的培养PBMC中诱导产生的IL-10明显多于猫变应原。
PreS-Cat 5和PreS-Cat 1是用于猫过敏AIT的极具前景的分子疫苗候选物，它们在单一PreS融合蛋白中结合了Fel d 1、Fel d 4和Fel d 7肽段。
