PHOSPHOMANNOPROTEIN ADHESIN AS A VACCINE CANDIDATE

磷酸甘露糖蛋白粘附素作为候选疫苗

• 批准号: 6235293
• 负责人: Jim E. Cutler
• 金额: $ 10.8万
• 依托单位: LUNDQUIST INSTITUTE FOR BIOMEDICAL INNOVATION AT HARBOR-UCLA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-01-01 至 1997-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6235293
• 关键词: Candida albicans; active immunization; adhesin; antifungal antibody; candidiasis; cell adhesion; fungal vaccines; granulocytopenia; intravital microscopy; laboratory mouse; liposomes; microorganism culture; passive immunization; phosphoproteins; severe combined immunodeficiency

The pathogenesis of hematogenous disseminated candidiasis appears to involve adhesion events between yeast cells of Candida albicans and specific host tissues. We hypothesize that host antibodies specific for candidal adhesins alter the pathogenesis and may aid host survival. In the PI's laboratory, candidal adhesins have been isolated that cause specific yeast cell adherence to mouse splenic marginal zone macrophages. These adhesins are part of the phosphomannoprotein (PMP) complex on the candidal cell surface. Vaccines made of solubilized adhesins encapsulated in liposomes provoke antibody responses in mice against the adhesins. Vaccinated animals have increased resistance against disseminated candidiasis, their serum neutralizes adhesin activity, prevents yeast cell attachment to the spleen, and appears to transfer protection. Monoclonal antibodies (mAbs) against the PMP-derived adhesins are available in the PI's laboratory. The effects of polyclonal and mAbs on adherence interactions with various tissues will be extensively evaluated by adherence assays. The specific aims are to: 1. Determine the optimal immunization protocol for protective responses in normal mice. Variables include adhesin composition, dose, effect of adjuvants, routes of administration and booster schedule. 2. Determine the effect of the vaccination in prevention of disseminated candidiasis. Immunization effectiveness will be assessed in normal mice (BALB/c female and male mice and a BALB/c crossed outbread strain). 3. Use passive transfer experiments to determine if antibodies are responsible for immunity. Immune sera from vaccinated animals, mAbs specific for the adhesins of C. albicans, and mAbs against hydrophobic proteins will be tested for their ability to protect naive animals against disseminated candidiasis. Immunologically competent mice, T-cell deficient (nu/nu), T- and B- cell deficient (SCID), and mice with induced neutropenia (mAb RB6-8C5 treated) will be tested. 4. Initiate investigations on mechanisms of protection induced by the vaccine and mAbs. The ex vivo assay, the capillary tube shear-dependent adhesion assay, the endothelial adherence assay, and in vivo intravital microscopic method will be used to determine the effect of immune sera and protective mAbs on adherence characteristics of C. albicans to various host cells, tissues and glycoproteins. The effect of immune sera and mAbs on adherence characteristics of complement opsonized cells and unopsonized cells will be examined. The results may well lead to new preventive and therapeutic strategies for disseminated candidiasis.

血行播散性念珠菌病的发病机制似乎 涉及白色念珠菌酵母细胞之间的粘附事件， 特定的宿主组织 我们假设，宿主抗体特异于 念珠菌粘附素改变发病机制并可帮助宿主存活。 在 PI实验室已经分离出了念珠菌粘附素 特异性酵母细胞粘附于小鼠脾边缘区巨噬细胞。 这些粘附素是磷酸甘露糖蛋白（PMP）复合物的一部分， 念珠菌细胞表面 由溶解的粘附素制成的疫苗 包封在脂质体中， 粘附素。 接种疫苗的动物对 播散性念珠菌病，其血清中和粘附素活性， 阻止酵母细胞附着在脾脏上， 保护 抗PMP衍生的单克隆抗体（mAb） 粘附素可在PI的实验室获得。 多克隆的影响 和mAb与各种组织的粘附相互作用， 通过粘附测定进行广泛评价。 具体目标是：1. 确定保护性应答的最佳免疫方案， 正常小鼠 变量包括粘附素组成、剂量、 佐剂、给药途径和加强方案。 2.确定 预防播散性念珠菌病的效果。 将在正常小鼠（BALB/c雌性）中评估免疫效力 和雄性小鼠和BALB/c杂交外系小鼠）。 3.使用被动 转移实验，以确定抗体是否负责 免疫力 来自接种动物的免疫血清，特异于 C.粘附素白念珠菌，和针对疏水蛋白的mAb将被 测试了它们保护幼稚动物免受传播性疾病的能力， 念珠菌病 免疫活性小鼠，T细胞缺陷型（nu/nu）， T-和B-细胞缺陷型（SCID）和诱导中性粒细胞减少症小鼠（mAb RB 6 - 8 C5处理）。 4.发起调查 疫苗和mAb诱导的保护机制。 离体 毛细管剪切依赖性粘附试验，内皮细胞粘附试验 将使用粘附试验和体内活体显微镜方法 确定免疫血清和保护性mAb对粘附的影响 C.白色念珠菌对各种宿主细胞、组织和 糖蛋白 免疫血清和单克隆抗体对粘附的影响 补体调理的细胞和未调理的细胞的特征将 接受检查。 这些结果很可能会导致新的预防和治疗 传播性念珠菌病的治疗策略。