Cancer Vaccines,Treatment of the Future: With Emphasis on HER2-Positive Breast Cancer

Breast cancer is one of the leading causes of death in women. With improvements in early-stage diagnosis and targeted therapies, there has been an improvement in the overall survival rate in breast cancer over the past decade. Despite the development of targeted therapies, tyrosine kinase inhibitors, as well as monoclonal antibodies and their toxin conjugates, all metastatic tumors develop resistance, and nearly one-third of HER2+ breast cancer patients develop resistance to all these therapies. Although antibody therapy has shown promising results in breast cancer patients, passive immunotherapy approaches have limitations and need continuous administration over a long period. Vaccine therapy introduces antigens that act on cancer cells causing prolonged activation of the immune system. In particular, cancer relapse could be avoided due to the presence of a longer period of immunological memory with an effective vaccine that can protect against various tumor antigens. Cancer vaccines are broadly classified as preventive and therapeutic. Preventive vaccines are used to ward off any future infections and therapeutic vaccines are used to treat a person with active disease. In this article, we provided details about the tumor environment, different types of vaccines, their advantages and disadvantages, and the current status of various vaccine candidates with a focus on vaccines for breast cancer. Current data indicate that therapeutic vaccines themselves have limitations in terms of efficacy and are used in combination with other chemotherapeutic or targeting agents. The majority of breast cancer vaccines are undergoing clinical trials and the next decade will see the fruitfulness of breast cancer vaccine therapy.     

Combining Cancer Vaccines with Immunotherapy: Establishing a New Immunological Approach

Therapeutic cancer vaccines have become increasingly qualified for use in personalized cancer immunotherapy. A deeper understanding of tumor immunology and novel antigen delivery technologies has assisted in optimizing vaccine design. Therapeutic cancer vaccines aim to establish long-lasting immunological memory against tumor cells, thereby leading to effective tumor regression and minimizing non-specific or adverse events. However, due to several resistance mechanisms, significant challenges remain to be solved in order to achieve these goals. In this review, we describe our current understanding with respect to the use of the antigen repertoire in vaccine platform development. We also summarize various intrinsic and extrinsic resistance mechanisms behind the failure of cancer vaccine development in the past. Finally, we suggest a strategy that combines immune checkpoint inhibitors to enhance the efficacy of cancer vaccines.     

无细胞百白破b型流感嗜血杆菌联合疫苗的研制

目的研制无细胞百白破b型流感嗜血杆菌联合疫苗(DTaP/Hib)。方法按不同抗原配比配制3组联合疫苗,分别检测疫苗的效价及安全性,从中选择最佳配比配制3批联合疫苗,并用相应批原液,按相同配比配制3批DTaP和3批Hib疫苗作为对照,检测联合疫苗中抗原的相容性。结果3组配比的联合疫苗效价及安全性均达到《中国药典》三部(2005版)要求,联合疫苗中以每毫升含AcP18μgPN、D25Lf、T7Lf和Hib多糖抗原20μg为最佳配比。动物实验证明联合疫苗各抗原间不存在免疫干扰。结论已成功研制4种抗原配比合理的DTaP/Hib联合疫苗。     

Radial porous SiO2 nanoflowers potentiate the effect of antigen/adjuvant in antitumor immunotherapy

Here, we reported a cancer nanovaccine based on SiO₂ nanoflowers with a special radial pore structure, which greatly enhanced cross-presentation and induced the production of cytotoxic T lymphocyte cells secreting granzymes B and interferon-γ. The antigen ovalbumin was covalently conjugated onto the as-synthesized hierarchical SiO₂ nanoflowers, and the adjuvant cytosine-phosphate-guanine was electrostatically adsorbed into their radial pore by simple mixing before use. The nanovaccine exhibited excellent storage stability without antigen release after 27 days of incubation, negligible cytotoxicity to dendritic cells, and a high antigen loading capacity of 430 ± 66 mg·g⁻¹ support. Besides, the nanovaccine could be internalized by dendritic cells via multiple pathways. And the enhancement of antigen/adjuvant uptake and lysosome escape of antigen were observed. Noteworthy, in vitro culture of bone marrow-derived dendritic cells in the presence of nanovaccine proved the activation of dendritic cells and antigen cross-presentation as well as secretion of proinflammatory cytokines. Besides, in vivo study verified the targeting of nanovaccine to draining lymph nodes, the complete suppression of tumor in six out of ten mice, and the triggering of notable tumor growth delay. Overall, the present results indicated that the nanovaccine can be served as a potential therapeutic vaccine to treat cancer.     

人禽流感裂解疫苗对小鼠的免疫原性观察

目的观察人禽流感裂解疫苗对小鼠的免疫原性。方法将不同血凝素含量(20、30、45μg/ml)的铝佐剂和无佐剂人禽流感裂解疫苗各3批分别经腹腔注射免疫小鼠,0.5 ml/只,每批疫苗又分为1针、2针和3针组,每组10只,每针间隔1周,同时设空白对照组。首针免疫后21 d,分别采血,分离血清,检测血凝抑制抗体效价和中和抗体效价。结果 1针、2针组各3批无佐剂疫苗免疫小鼠的血凝抑制抗体效价和中和抗体效价分别小于1∶40和1∶200;2针、3针组各3批铝佐剂疫苗的血凝抑制抗体效价均大于1∶50,2针组20、30μg/ml血凝素铝佐剂疫苗的中和抗体效价均大于1∶200;2针、3针组20、30与45μg/ml血凝素铝佐剂疫苗的血凝抑制抗体效价和中和抗体效价差异均无统计学意义(P>0.05);且2针、3针组3批铝佐剂疫苗的血凝抑制抗体效价和中和抗体效价均明显高于相应的3批无佐剂疫苗。结论铝佐剂疫苗对小鼠的免疫原性明显优于无佐剂疫苗,且20、30μg/ml血凝素铝佐剂疫苗接种2针可获得理想的免疫效果。     

卵清蛋白国家定量参考品的建立

目的建立卵清蛋白国家定量参考品。方法用德国试剂盒测定不同厂家、不同级别卵清蛋白的含量,筛选与试剂盒标准卵清蛋白含量符合率最高的样品作为参考品原料,并对参考品保护剂进行验证。将参考品贮存母液系列稀释后,经3个实验室协作标定,确定其标示量。结果选取SigmaGⅡ作为参考品原料;参考品保护剂对卵清蛋白测定结果无影响,并可显著提高参考品的稳定性;经协作标定,确定浓度为15、10、5和2.5ng/ml系列参考品的标示量分别为(17.96±1.00)、(12.25±1.51)、(6.79±1.14)和(3.11±0.31)ng/ml。结论已建立了含量准确,重复性和线性较好的卵清蛋白国家定量参考品。     

Antibody Induction Directed against the Tumor‐Associated MUC4 Glycoprotein

Mucin glycoproteins are important diagnostic and therapeutic targets for cancer treatment. Although several strategies have been developed to explore anti‐tumor vaccines based on MUC1 glycopeptides, only few studies have focused on vaccines directed against the tumor‐associated MUC4 glycoprotein. MUC4 is an important tumor marker overexpressed in lung cancer and uniquely expressed in pancreatic ductual adenocarcinoma. The aberrant glycosylation of MUC4 in tumor cells results in an exposure of its peptide backbone and the formation of tumor‐associated glycopeptide antigens. Due to the low immunogenicity of these endogenous structures, their conjugation with immune stimulating peptide or protein carriers are required. In this study, MUC4 tandem‐repeat glycopeptides were conjugated to the tetanus toxoid and used for vaccination of mice. Immunological evaluations showed that our MUC4‐based vaccines induced very strong antigen‐specific immune responses. In addition, antibody binding epitope analysis on glycopeptide microarrays, were demonstrating a clear glycosylation site dependence of the induced antibodies.     

明胶微球乙型肝炎疫苗的研究

用明胶作为原材料制备出10～100μm直径的明胶微球，用来包裹乙肝疫苗抗原，其包裹率为90％以上。免疫动物后抗－HBS在3～4个月达到高峰，10个月仍能维持较高水平（S／N为80～90）。微球疫苗优于Al佐剂疫苗，也优于含Al佐剂微球疫苗。明胶微球制备方法简单，抗原不接触有机溶剂。用琼脂糖、明胶＋阿拉伯胶等均能制成微球，且均可包裹成功。明胶微球可以成功地制备出HB－DT微球疫苗，关于它们的制备条件和免疫效果有待进一步观察和改进。     

rBS-WC霍乱疫苗的动物免疫研究

rBS与WC联合免疫比单纯免疫效果好；小鼠或家兔的免疫间隔适当缩短未见影响免疫保护力；小鼠一次大剂量口服疫苗后可获良好保护。rBS－WC抗原、吸附霍乱类毒素疫苗（上海苗）和吸附霍乱疫苗（武汉苗）经家兔肌肉免疫，武汉苗未见抗CT反应，对CT攻击无保护，对Eltor（小川）活菌攻击保护较弱，上海苗抗CT反应比rBS－WC低。家兔口服rBS－WC半年后，抗CT及杀弧菌抗体维持较高水平，显示其动物免疫的持久性。     

Strategies for Synthesizing and Enhancing the Immune Response of Cancer Vaccines Based on MUC1 Glycopeptide Antigens

Cancer vaccines are based on a vaccinology strategy whereby the patient's immune system is harnessed to induce a specific immune response to kill cancer cells and comprises two categories: prophylactic and therapeutic. Glycoprotein mucin 1 (MUC1), which is overexpressed and poorly glycosylated on cancer cells, is one of the most promising candidates for the development of new cancer vaccines. However, it should be noted that mucin-like glycopeptides are poorly immunogenic and unable to elicit effective and long-lasting immune responses. Therefore, MUC1-derived tumor antigens need to be conjugated with immune activators. This review focuses on the synthesis of MUC1 glycopeptides, provides an overview of recently advanced designs of vaccines based on MUC1, and compares the advantages and disadvantages of the various strategies devised to date.     

短期异常低温对重组乙型肝炎疫苗效力相关因素的影响

目的模拟重组乙型肝炎(简称乙肝)疫苗在冷藏存储过程中发生的异常低温情况,探讨短期异常低温储存对乙肝疫苗效力相关因素的影响。方法选取3个不同表达系统(酿酒酵母、汉逊酵母、CHO细胞)来源的乙肝疫苗,分别于0、-7、-20℃储存1或7 d,检测疫苗的吸附完全性、上清中铝离子含量、效价和体外相对效力,比较乙肝疫苗经短期异常低温储存后与2~8℃正常储存条件下的差异。结果经短期异常低温储存后,疫苗的吸附完全性、疫苗上清中铝离子含量未发生变化;3种乙肝疫苗的ED50在0.16~0.68μg之间波动;汉逊酵母乙肝疫苗体外相对效力的变化幅度不超过10%,酿酒酵母乙肝疫苗在-20℃冻存7 d后相对效力较2~8℃储存下降21.8%。结论短期异常低温储存后,乙肝疫苗仍能保持较好的吸附完全性,非胶体状态铝含量未发生变化,疫苗效价和体外相对效力在部分异常储存条件下出现下降,但仍符合质量标准要求。     

海藻酸凝胶性质对蛋白质扩散的影响

通过观察冷冻干燥海藻酸凝胶的断面扫描电镜(SEM)照片与卵清蛋白从海藻酸凝胶中的释放试验,分析了海藻酸凝胶性质对蛋白质在凝胶中扩散的影响。凝胶的SEM照片可见,海藻酸钙的冷冻干燥颗粒内为较大的圆孔,海藻酸锌凝胶内为较小的长孔,表明海藻酸锌高分子链在凝胶颗粒中的体积分率相对较大同时刚性较强;卵清蛋白从海藻酸凝胶颗粒中释放的试验结果表明,由于上述海藻酸锌凝胶的特性,导致海藻酸锌对卵清蛋白扩散阻滞作用相对较强;根据试验数据计算得卵清蛋白在海藻酸钙、海藻酸锌凝胶颗粒中的扩散系数分别为1.19×10-7、0.07×10-7cm2/s,利用阻滞模型计算得海藻酸锌高分子链在凝胶颗粒中体积分率约为海藻酸钙高分子链在凝胶颗粒中体积分率的1.7倍。     

不同的流行性乙型脑炎疫苗在小鼠体内的免疫原性比较

比较乙型脑炎活疫苗与灭活疫苗在小白鼠的免疫原性。结果表明以腹腔攻击法测定,活疫苗免疫1钟后7天和14天的保护率无下降,而灭活疫苗免疫2针后14天的保护率较7天下降30％～50％。以脑内攻击法测定,活疫苗免疫1外或2针的保护率为70％～90％。而灭活疫苗免疫2针的保护率仅为10％～33％。活疫苗免疫后动物中和抗体水平虽然很低（1：5）,但仍有很强的保护力。提示活疫苗免疫的保护力除体液免疫外可能还存在细胞免疫。     

乙肝-白-百-破四联疫苗的实验研究

应用乙肝抗原与白-百-破抗原配制成Al（OH）3吸附四联疫苗，经实验室检测HBsAg能完全被吸附，对小白鼠的免疫效果较单价乙肝疫苗明显增强。应用高pH吸附剂较低pH吸附剂免疫效果更好。在四联疫苗中，四种抗原间无干扰现象。四联疫苗经4℃保存8个月免疫效价无影响。     

鼠疫组分疫苗F1抗原、rV抗原含量的检测及其质量控制

目的采用双抗体夹心ELISA法检测鼠疫组分疫苗中F1和rV的抗原含量。方法利用F1、rV抗原单克隆抗体,对鼠疫组分疫苗原液进行抗原鉴别试验;分别应用F1、rV抗原双抗体夹心ELISA法对疫苗原液进行抗原定量检测;验证A(l OH)3佐剂吸附抗原的完全性;将疫苗成品于4℃放置18个月,分别于1和18个月时取样,用建立的双抗体夹心ELISA法检测F1和rV抗原含量,分析抗原的稳定性;对3批鼠疫菌rV抗原原液3步纯化工艺进行验证。结果鼠疫组分疫苗原液中的F1和rV抗原具有良好的反应原性;用建立的双抗体夹心ELISA法检测4批F1和rV抗原原液中F1和rV抗原的含量与Lowry法检测结果的误差均在±20%以内;4批鼠疫组分疫苗离心后的上清液中均未检测到F1和rV抗原,表明A(lOH)3佐剂吸附抗原完全;4℃保存18个月,疫苗中的F1和rV抗原含量稳定;3批鼠疫菌rV抗原原液经阴离子交换层析、疏水层析、凝胶过滤层析3步纯化,rV抗原在纯度增加的同时,抗原含量也增加。结论已建立的F1、rV抗原双抗体夹心ELISA法可用于鼠疫组分疫苗中F1和rV抗原的定量检测。     

Capto Core 700在流感疫苗中去除卵清蛋白的应用

目的用新型复合型填料Capto Core 700层析介质纯化鸡胚流感疫苗,以降低卵清蛋白的残留水平。方法用Capto Core700进一步纯化鸡胚培养的不同亚型的流感病毒纯化后原液及超滤浓缩液,参考《中国药典》三部(2010版)检测纯化前、后样品中总蛋白含量、血凝素含量及卵清蛋白残留量。结果卵清蛋白残留量较纯化前降低约10倍,血凝素和总蛋白含量基本保持不变。结论 Capto Core700新型填料可有效去除鸡胚流感疫苗中的卵清蛋白残留量,从而提高产品质量。     

Al-Pickering乳液提高口蹄疫疫苗热稳定性的应用

口蹄疫疫苗是一种重要的兽用疫苗,对畜牧业的发展具有重要作用。但其存在抗原热稳定性差、易失活等问题。目前,有研究者对口蹄疫病毒五聚体交界处的氨基酸改造,作为提高口蹄疫疫苗热稳定性的策略之一。然而这种方法操作复杂,要针对不同血清型病毒衣壳进行分别设计。为解决这一问题,本工作提出将抗原稳定与佐剂设计相结合的策略,构建Pickering乳液,以期提高口蹄疫疫苗的热稳定性。采用水热法制备得到了球状、棒状、片状氢氧化铝颗粒,在此基础上以角鲨烯为油相制备粒径均一的Al-Pickering乳液。随后采用差示扫描荧光法评价了灭活口蹄疫病毒(iFMDV)与Al-Pickering乳液结合后的热稳定性,结果表明各组Al-Pickering乳液对iFMDV热稳定性均有提高,其中棒状-Pickering乳液提升效果最佳,将iFMDV裂解温度提高了1.7℃。同时,动物实验结果表明Al-Pickering乳液能够增强iFMDV特异性抗体IgG分泌水平。综上,制备的Al-Pickering乳液能够稳定抗原结构并增强体液免疫水平,且制备工艺简单。该研究为提高疫苗热稳定性的佐剂研究提供了新的选择。     

氢氧化铝佐剂对肠道病毒71型灭活疫苗诱导小鼠细胞免疫应答的影响

目的评价氢氧化铝佐剂对肠道病毒71型(Enterovirus 71,EV71)灭活疫苗诱导小鼠细胞免疫应答的影响。方法用含铝佐剂及无佐剂EV71灭活疫苗免疫BALB/c小鼠,并设生理盐水对照组。于加强免疫后7 d采血,进行小鼠脾单个核细胞(Mononuclear cell,MNC)的分离及CD8+T细胞的去除,采用酶联免疫斑点法(ELISPOT)检测经EV71疫苗原液或VP2-36刺激后的小鼠脾MNC分泌IFNγ水平;应用液相芯片技术(LUMINEX)检测经EV71疫苗原液刺激后的小鼠脾MNC分泌IL-2、IL-4、IL-5、IL-6和IL-10水平;采用体外微量中和试验法检测小鼠血清中和抗体效价。结果 BALB/c小鼠经2次免疫后,铝佐剂疫苗组小鼠脾MNC的IFNγSFC值显著高于无佐剂疫苗组(P均<0.05);铝佐剂疫苗组分泌IL-6和IL-10水平显著高于无佐剂疫苗组(P均<0.05);铝佐剂与无佐剂疫苗组小鼠血清EV71中和抗体阳转率均达到100%,铝佐剂疫苗组诱导的中和抗体效价显著高于无佐剂疫苗组(P<0.01)。结论 EV71灭活疫苗可诱导BALB/c小鼠产生特异性IFNγ、IL-2、IL-6和IL-10应答,铝佐剂可同时增强EV71灭活疫苗的Th1和Th2类免疫应答。     

Vaccines for Non-Viral Cancer Prevention

Cancer vaccines are a type of immune therapy that seeks to modulate the host’s immune system to induce durable and protective immune responses against cancer-related antigens. The little clinical success of therapeutic cancer vaccines is generally attributed to the immunosuppressive tumor microenvironment at late-stage diseases. The administration of cancer-preventive vaccination at early stages, such as pre-malignant lesions or even in healthy individuals at high cancer risk could increase clinical efficacy by potentiating immune surveillance and pre-existing specific immune responses, thus eliminating de novo appearing lesions or maintaining equilibrium. Indeed, research focus has begun to shift to these approaches and some of them are yielding encouraging outcomes.     

Rational Design of a Glycoconjugate Vaccine against Group A Streptococcus

No commercial vaccine is yet available against Group A Streptococcus (GAS), major cause of pharyngitis and impetigo, with a high frequency of serious sequelae in low- and middle-income countries. Group A Carbohydrate (GAC), conjugated to an appropriate carrier protein, has been proposed as an attractive vaccine candidate. Here, we explored the possibility to use GAS Streptolysin O (SLO), SpyCEP and SpyAD protein antigens with dual role of antigen and carrier, to enhance the efficacy of the final vaccine and reduce its complexity. All protein antigens resulted good carrier for GAC, inducing similar anti-GAC IgG response to the more traditional CRM₁₉₇ conjugate in mice. However, conjugation to the polysaccharide had a negative impact on the anti-protein responses, especially in terms of functionality as evaluated by an IL-8 cleavage assay for SpyCEP and a hemolysis assay for SLO. After selecting CRM₁₉₇ as carrier, optimal conditions for its conjugation to GAC were identified through a Design of Experiment approach, improving process robustness and yield This work supports the development of a vaccine against GAS and shows how novel statistical tools and recent advancements in the field of conjugation can lead to improved design of glycoconjugate vaccines.