艾滋病疫苗与中和抗体 清华大学张林琦 2014 年 10 月 20 日

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1 艾滋病疫苗与中和抗体 清华大学张林琦 2014 年 10 月 20 日

2 Current situation 有病无苗 有苗不优 优苗不种

3 Lu L, and Zhang L., Nature 2008

4 Rapid rise in sexual transmission of HIV Shang H and Zhang L., Nature 2012

5 Risk factors in different regions

6 三个关键方面

7

8 以毒攻毒的哲学理念 Practice of variolation originated in China and widely used by 1500 s to control smallpox Lady Mary Wortley Montagu introduced Variolation to England in 1700 s.

9 Edward Jenner ( ) Edward Jenner, FRS, (17 May January 1823) was an English country doctor who studied nature and his natural surroundings from childhood and practiced medicine in Berkeley, Gloucestershire, England. He is famous as the first doctor to introduce and study the smallpox vaccine

10 疫苗接种后人体的正常反应

11 Smallpox eradication in nm Edward Jenner ( ) Edward Jenner ( )

12 Prevention of poliovirus infection Most countries use OPV because of its ability to induce local immunity and also it is much cheaper to produce than IPV. The normal response rate to OPV is close to 100%. OPV is used for the WHO poliovirus eradication campaign. Because of the slight risk of paralytic poliomyelitis, some Scandinavian countries have reverted to using IPV. Because of the lack of local immunity, small community outbreaks of poliovirus infections have been reported. Poliovirus was targeted for eradication by the WHO and Gates Foundation. To this end, an extensive monitoring network had been set up. Poliovirus has been eradicated from most regions of the world except the Indian subcontinent and sub-saharan Africa. It is possible that the WHO target may be achieved.

13 泰国 RV144 是唯一具保护性的临床试验 Challenges ahead: Improve vaccine efficacy and longevity of protection

14 Mucosal prime with a replicating vaccinia-based vaccine Prime with MVTT SIVgpe and boost with Ad5 SIVgpe Protection from SIV infection /SAIDS wk Challenge with pathogenic SIVmac239 ( 5 x 10 5 intrarectal challenge)

15 Protective effects of the MVTT ioin +Ad im regimen in Chinese monkeys

16 艾滋疫苗研发的主要障碍 自然感染状态下, 保护性免疫反应不详 重复感染现象已被证实 传统的疫苗策略至今没有一个成功 变异与逃逸能力 对抗体的不敏感性 没有理想的动物模型

17 First Nobel prize and serum treatment One of the first bottles (1895) of diphtheria antitoxin produced at the Hygienic Laboratory, which became the NIH in 1930 白喉抗毒素 From Dr. Bailin Tu,

18 Monoclonal antibody (mab) Georges Jean Franz Köhler ( ) César Milstein ( ) Niels Kaj Jerne, ( ) 1984

19 Original publication in Nature Nature 256, (7 August 1975) Continuous cultures of fused cells secreting antibody of predefined specificity G. KÖ HLER & C. MILSTEIN MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK Abstract THE manufacture of predefined specific antibodies by means of permanent tissue culture cell lines is of general interest. There are at present a considerable number of permanent cultures of myeloma cells and screening procedures have been used to reveal antibody activity in some of them. This, however, is not a satisfactory source of monoclonal antibodies of predefined specificity. We describe here the derivation of a number of tissue culture cell lines which secrete anti-sheep red blood cell (SRBC) antibodies. The cell lines are made by fusion of a mouse myeloma and mouse spleen cells from an immunised donor. To understand the expression and interactions of the Ig chains from the parental lines, fusion experiments between two known mouse myeloma lines were carried out.

20 Hybridoma and mab Immunized Animal Isolate B-cells contain desired antibody Myeloma cells imparts immortality Hybridoma Fusions Screen clones and expand cell line Antibody producing clone

21 New technologies for isolating mabs from animals and humans Wilson P, NRI, 2012

22 Protective Immunity? Protective antibody response? 保护性免疫反应? 保护性抗体反应?

23 Key roles of neutralizing antibodies Corti and Lanzavecchia, Annnu. Rev. Immunol. 2013

24 Immune response against HIV-1 Johnston and Fauci, NEJM, 2007

25 Virus and antibody interaction Letvin and Walker, Nat. Medicine 2003

26 New technology in isolating mabs Antigenspecific B cells

27 Single B cells based mab isolation 分选 单个细胞 1. 单个抗原特异性浆细胞分选 2. 单个抗原特异性记忆 B 淋巴细胞分选 3. 分选并培养记忆 B 淋巴细胞 B 细胞培养 抗体结合和中和实验 细胞转染 RT/PCR L L 抗体基因序列分析 VH + VL Ig V H Ig V L PCMV PCMV L 线性抗体重链基因 L VH VL + 线性抗体轻链基因 IgG1 CH CK or CL BGH Poly A BGH Poly A

28 PCRb IgH PCRb IgK PCRb IgL

29 R002 R026 R041 R001 M R002 R026 R041 R001 M R002 R026 R041 R001 M R002 R026 R041 R001 M

30 HIV-1 Spike and Its Recognition by Neutralizing Antibodies The 20A cryoelectron tomogram of the HIV-1 BaL isolate viral spike (Liu et al., 2008) is shown in gray, fitted with three copies of the HIV-1 gp120 core in the CD4-bound conformation (Pancera et al., 2010a), with modeled glycans and with modeled sites of Env vulnerability colored red (CD4-binding site), green (glycan N160 in V1/V2), blue (glycan N332 at the base of V3), and cyan (MPER of gp41). Effective mabs are shown that recognize each site (see main text for fuller descriptions and references). Movie S1 available online shows the viral spike and recognizing antibodies. Kwong and Mascola, Immunity 2012

31 Reverse vaccinology approach 反向疫苗学 1 2

32 Specificity of selection process

33 The full-length HIV-1 CNE11 sequence VRC01 selected longest fragment VRC01 selected shortest fragment VRC01 selected fragments core Consensus sequences of yeast clones positively selected by VRC01 are shown aligned with the original full-length HIV-1 subtype B sequence used to construct the random fragment yeast library Wang H. and Zhang L., unpublished

34 Selected fragments contain epitope

35 Selected fragments contain epitopes Structure of antibody VRC01 in complex with HIV-1 gp120 Zhou T et al, Nature, 2010 Structure of the V1/V2 domain of HIV-1 gp120 in complex with PG9 McLellan JS et al, Nature, 2011

36 Structure rearrangement of RSV F McLellan et al., Science 2013

37 Crystal structure of mab D25 with RSV F McLellan et al., Science 2013

38 Engineered RSV F to preserve antigenic site McLellan et al., Science 2013

39 Immunogenicity of engineered RSV F trimers McLellan et al., Science 2013

40 Challenges and Opportunities Dynamic understanding of protective antibody response throughout the course of infection. Correlate studies on antigenic domains with protective antibody response. Identify the antigenic domains recognized by broadly neutralizing antibodies for rational design and optimization of vaccines.

41 Challenges and opportunities ahead

42 Acknowledgements National Science and Technology Major Project MOST and MOH Bill and Melinda Gates Foundation Jassen Investigator Award

43 Acknowledgements