Tellier M C, Pu R, Pollock D, Vitsky A, Tartaglia J, Paoletti E, Yamamoto J K
Department of Pathobiology, School of Veterinary Medicine, University of Florida, Gainesville, USA.
AIDS. 1998 Jan 1;12(1):11-8. doi: 10.1097/00002030-199801000-00002.
To evaluate the immunogenicity and prophylactic efficacy of immunization schemes employing a recombinant canarypoxvirus ('ALVAC')-based feline immunodeficiency virus (FIV) vaccine alone or in combination with an inactivated FIV-infected cell vaccine against homologous and heterologous FIV challenges in cats.
Specific pathogen-free cats were given a total of three immunizations with subtype A vaccines and challenged 4 weeks after the final immunization with 50 median animal infectious doses (ID50) of FIV-Petaluma, a subtype A isolate. Following the initial challenge, protected cats received a second challenge with 75 ID50 of FIV-Bangston, a subtype B isolate. FIV-specific humoral and cell-mediated responses were measured to determine the immune correlates of protection.
Two of three cats immunized with the ALVAC FIV recombinants alone were protected from homologous FIV challenge in the presence of FIV-specific cytotoxic T-lymphocyte (CTL) responses but in the absence of FIV-specific humoral responses. All three cats immunized with the ALVAC-FIV recombinant and boosted with FIV-infected cell vaccine were also protected from homologous FIV challenge in the presence of both FIV-specific CTL and humoral responses. Partial to full protection was observed in ALVAC-FIV/FIV-infected cell vaccine-immunized cats against a heterologous FIV challenge given 8 months after the initial challenge. Two out of three cats had transient infection and the remaining cat had no sign of FIV infection at a dose at which all three control cats were readily infected.
Immunization schemes employing ALVAC-based FIV vaccines in combination with inactivated FIV-infected cell vaccine generate protective immune responses that can cross-react with FIV isolates that are genetically distinct from the vaccine strains.
评估单独使用基于重组金丝雀痘病毒（“ALVAC”）的猫免疫缺陷病毒（FIV）疫苗或与灭活的FIV感染细胞疫苗联合使用的免疫方案对猫同源和异源FIV攻击的免疫原性和预防效果。
对无特定病原体的猫总共进行三次A型疫苗免疫，并在最后一次免疫后4周用50个中位数动物感染剂量（ID50）的A型分离株FIV-Petaluma进行攻击。初次攻击后，受保护的猫接受第二次攻击，用75 ID50的B型分离株FIV-Bangston。测量FIV特异性体液和细胞介导反应以确定保护的免疫相关性。
单独用ALVAC FIV重组体免疫的三只猫中有两只在存在FIV特异性细胞毒性T淋巴细胞（CTL）反应但不存在FIV特异性体液反应的情况下免受同源FIV攻击。用ALVAC-FIV重组体免疫并用FIV感染细胞疫苗加强免疫的所有三只猫在存在FIV特异性CTL和体液反应的情况下也免受同源FIV攻击。在初次攻击后8个月给予异源FIV攻击时，在ALVAC-FIV/FIV感染细胞疫苗免疫的猫中观察到部分至完全保护。三只猫中有两只出现短暂感染，其余一只猫在所有三只对照猫都容易感染的剂量下没有FIV感染迹象。
采用基于ALVAC的FIV疫苗与灭活的FIV感染细胞疫苗联合使用的免疫方案可产生保护性免疫反应，该反应可与基因上不同于疫苗株的FIV分离株发生交叉反应。
