疟原虫代谢分泌物在增强蛋白抗原免疫保护力中的作用
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摘要
疟疾是由疟原虫引起的,是最严重的传染病之一,每年导致100万人死亡,目前109个国家正遭受疟疾感染的危险。疟疾是由按蚊传播,随着叮咬人体而将疟原虫注入人体血液循环中,它可以导致低血糖症、发热、贫血等临床症状。目前有四种人疟和四种鼠疟,其中夏氏疟原虫是研究恶性疟原虫最佳的小鼠模型。
目前研发的用于抵抗疟疾的疫苗种类有很多,亚单位疫苗是研究最多的。它可以引起很强的体液免疫,但细胞免疫较弱,不能引起持久的免疫保护力。亚单位疫苗需要佐剂的辅助来增强免疫反应。MSP1是最重要的亚单位候选疫苗,可以引起一定的保护力。它经一系列切割最后只剩C端19kDa经GPI连接在虫表面并进入红细胞中。有前人报道发现从疟原虫体外培养的上清中有某些物质可以与疟疾感染的病人的阳性血清发生作用。
因此本实验我们想研究MSP1和疟原虫培养上清共同免疫的效果。首先利用大肠杆菌表达系统获得夏氏疟原虫AS株MSP1蛋白C端11kDa;其次体外短期培养夏氏疟原虫获得代谢分泌物(ES)。将MSP1与代谢分泌物共同免疫小鼠,检测感染率、ELISA检测抗体滴度;免疫小鼠的脾细胞培养,研究细胞因子的分泌和细胞激活状态。实验发现:(a)MSP1以ES为佐剂免疫可以有效抑制血虫水平;产生较高的抗体水平,主要有IgG1、IgG2c和IgG2b;(b)激活了树突状细胞,使CD40、CD86分子表达升高,MHC-II表达下降;(c)激活了CD4+T细胞,使其表面分子CD62L表达下降;(d)诱导淋巴细胞的增殖,产生较高的IFN-γ、IL-12和IL-10。本研究第一次将代谢分泌物作为新型佐剂。我们的研究结果揭示了抗疟疾免疫诱导的复杂机制,并可能对疟疾疫苗的研发具有重要意义。
Malaria caused by infection with Plasmodium parasite is one of the most serious infectious diseases, which causes 1 million deaths every year. At present, more than 109 countries of the world are suffering from the risk of malaria infection. Malaria is transmitted by Anopheles, which bite human body and inject the parasites into blood circulation. Malaria infection causes severe clinical symptoms including anemia, hypoglycemia and fever. There are four species of Plasmodium that infect human. The rodent malaria parasite, Plasmodium chabaudi, is one of the model to study the Plasmodium falciparum infection.
Many vaccines against malaria are currently developed, among which subunit vaccines are most studied. The subunit vaccines can induce strong humoral immune response, but the cell-mediated immunity is weak and the protection is not long lasting. Adjuvants are often needed to help subunit vaccines to strengthen immune responses. Merozoite surface protein1 (MSP1) is a leading candidate vaccine antigen and has been shown to confer certain protection. MSP1 undergoes a series of proteolytic cleavages and finally the C-terminal GPI-anchored MSP119 remains on the parasite surface as it enters the RBC. It was reported that the supernatants from Plasmodium culture medium are recognized by the sera from malaria-infected adults.
In this study, we intend to determine the coimmune effects of P. chabaudi culture supernatant and MSP1. We first expressed the 11 kDa fragment of MSP1 C-terminal domain of Plasmodium chabaudi AS in Escherichia coli expression system. A protocol of short-term in vitro culture of Plasmodium chabaudi was used to acquire the excretory and secretary products (ES). After infecting mouse with MSP1 plus ES, we monitored the parasitemia and measured antibody titers using ELISA assay. In addition, spleen cells of the immunized mice were cultured to study the cytokine secretion and immune cell activation. We observed that: (a) immunization with MSP1 using ES as adjuvant effectively inhibited the parasitemia and induced higher levels of IgG1, IgG2c and IgG2b antibody titers; (b) CD11c+DC cells were activated, which showed up-regulated expression of CD40,CD86,but down-regulated expression of MHC-II; (c) the CD4+T cells were activated and CD62L were consequently down-regulated, and (d) splenocytes proliferated more vigorously and produced high levels of IFN-γ,IL-12 and IL-10. We report here first time that the excretory and secretary products can be used as a new immune adjuvant. Our results reveal the complex mechanisms of induction of anti-malarial immunity and may have important implication in development of malaria vaccines.
目前研发的用于抵抗疟疾的疫苗种类有很多,亚单位疫苗是研究最多的。它可以引起很强的体液免疫,但细胞免疫较弱,不能引起持久的免疫保护力。亚单位疫苗需要佐剂的辅助来增强免疫反应。MSP1是最重要的亚单位候选疫苗,可以引起一定的保护力。它经一系列切割最后只剩C端19kDa经GPI连接在虫表面并进入红细胞中。有前人报道发现从疟原虫体外培养的上清中有某些物质可以与疟疾感染的病人的阳性血清发生作用。
因此本实验我们想研究MSP1和疟原虫培养上清共同免疫的效果。首先利用大肠杆菌表达系统获得夏氏疟原虫AS株MSP1蛋白C端11kDa;其次体外短期培养夏氏疟原虫获得代谢分泌物(ES)。将MSP1与代谢分泌物共同免疫小鼠,检测感染率、ELISA检测抗体滴度;免疫小鼠的脾细胞培养,研究细胞因子的分泌和细胞激活状态。实验发现:(a)MSP1以ES为佐剂免疫可以有效抑制血虫水平;产生较高的抗体水平,主要有IgG1、IgG2c和IgG2b;(b)激活了树突状细胞,使CD40、CD86分子表达升高,MHC-II表达下降;(c)激活了CD4+T细胞,使其表面分子CD62L表达下降;(d)诱导淋巴细胞的增殖,产生较高的IFN-γ、IL-12和IL-10。本研究第一次将代谢分泌物作为新型佐剂。我们的研究结果揭示了抗疟疾免疫诱导的复杂机制,并可能对疟疾疫苗的研发具有重要意义。
Malaria caused by infection with Plasmodium parasite is one of the most serious infectious diseases, which causes 1 million deaths every year. At present, more than 109 countries of the world are suffering from the risk of malaria infection. Malaria is transmitted by Anopheles, which bite human body and inject the parasites into blood circulation. Malaria infection causes severe clinical symptoms including anemia, hypoglycemia and fever. There are four species of Plasmodium that infect human. The rodent malaria parasite, Plasmodium chabaudi, is one of the model to study the Plasmodium falciparum infection.
Many vaccines against malaria are currently developed, among which subunit vaccines are most studied. The subunit vaccines can induce strong humoral immune response, but the cell-mediated immunity is weak and the protection is not long lasting. Adjuvants are often needed to help subunit vaccines to strengthen immune responses. Merozoite surface protein1 (MSP1) is a leading candidate vaccine antigen and has been shown to confer certain protection. MSP1 undergoes a series of proteolytic cleavages and finally the C-terminal GPI-anchored MSP119 remains on the parasite surface as it enters the RBC. It was reported that the supernatants from Plasmodium culture medium are recognized by the sera from malaria-infected adults.
In this study, we intend to determine the coimmune effects of P. chabaudi culture supernatant and MSP1. We first expressed the 11 kDa fragment of MSP1 C-terminal domain of Plasmodium chabaudi AS in Escherichia coli expression system. A protocol of short-term in vitro culture of Plasmodium chabaudi was used to acquire the excretory and secretary products (ES). After infecting mouse with MSP1 plus ES, we monitored the parasitemia and measured antibody titers using ELISA assay. In addition, spleen cells of the immunized mice were cultured to study the cytokine secretion and immune cell activation. We observed that: (a) immunization with MSP1 using ES as adjuvant effectively inhibited the parasitemia and induced higher levels of IgG1, IgG2c and IgG2b antibody titers; (b) CD11c+DC cells were activated, which showed up-regulated expression of CD40,CD86,but down-regulated expression of MHC-II; (c) the CD4+T cells were activated and CD62L were consequently down-regulated, and (d) splenocytes proliferated more vigorously and produced high levels of IFN-γ,IL-12 and IL-10. We report here first time that the excretory and secretary products can be used as a new immune adjuvant. Our results reveal the complex mechanisms of induction of anti-malarial immunity and may have important implication in development of malaria vaccines.
引文
Ahlborg N, Ling IT, Howard W, Holder AA, Riley EM. (2002). Protective immune responses to the 42-kilodalton (kDa) region of Plasmodium yoelii merozoite surface protein 1 are induced by the C-terminal 19-kDa region but not by the adjacent 33-kDa region. Infection and Immunity. 70(2):820-5.
Awinder K.SOHAL , David. E. Arnot. (1993). PlasmodiumChabaudi: A Short-Term Invitro Culture Method And Its Application To Chloroquine Resistance Testing. Experimental Parasitology 76(3): 314-317
Blackman MJ, Heidrich HG, Donachie S, McBride JS, Holder AA. (1990). A single fragment of amalaria merozoite surface protein remains on the parasite during red cell invasion and is the target of invasion-inhibiting antibodies. Journal of Experimental Medicine 172(1): 379-382.
Blackman MJ, Scott-Finnigan TJ, Shai S, Holder AA. (1994). Antibodies Inhibit the
Protease-mediated Processing of a Malaria Merozoite Surface Protein. Journal of Experimental Medicine 180:389-393.
Bordmann G, Favre N, Rudin W. (1997). Malaria toxins: effects on murine spleen and bone marrow cell proliferation and cytokine production in vitro. Parasitology 115: 475-483.
Boutlis CS,Gowda DC, Naik RS, et al. (2002). Antibodies to Plasmodium falciparum Glycosylphosphatidylinositols: Inverse Association with Tolerance of
Parasitemia in Papua New Guinean Children and Adults. Infection and Immunity 70(9): 5052-5057.
Burns JM Jr, Flaherty PR, Nanavati P, Weidanz WP. (2004). Protection against plasmodium chabaudi Malaria Induced by Immunization with Apical Membrane
Antigen 1 and Merozoite Surface Protein 1 in the Absence of Gamma Interferon or Interleukin-4. Infection and Immunity 72(10): 5605-5612.
Burns JM Jr, Flaherty PR, Romero MM, Weidanz WP. (2003). Immunization against Plasmodium chabaudi malaria using combined formulations of apical membrane antigen-1 and merozoite surface protein-1. Vaccine 21(17-18): 1843-1852.
Bate CA, Taverne J, and Playfair JH (1989). Soluble malarial antigens are toxic and induce the production of tumour necrosis factor in vivo. Immunology.66(4):600-5.
Cheesman S, Tanabe K, Sawai H, et al. (2009). Strain-specific immunity may drive
adaptive polymorphism in the merozoite surface protein 1 of the rodent malaria parasite Plasmodium chabaudi. Infection, Genetics and Evolution 9(2): 248-255.
Crewther PE, Matthew ML, Flegg RH, Anders RF. (1996). Protective Immune Responses to Apical Membrane Antigen 1 of Plasmodium chabaudi Involve Recognition of Strain-Specific Epitopes. Infect Immun. 64(8):3310-7.
Daly TM and Long CA (1993). A recombinant 15-Kilodalton carboxyl-terminal fragment of Plasmodium yoelii 17XL merozoite surface protein linduces a protective immune response in mice. Infection and Immunity 61(6): 2462-2467.
Daly TM, Long CA. (1995). Humoral response to a carboxyl-terminal region of the merozoite surface protein-1 plays a predominant role in controlling blood-stage infection in rodent malaria. The Journal of Immunology 155: 236-243.
Darko CA, Angov E, Collins WE, et al. (2004). The Clinical-Grade 42-Kilodalton Fragment of Merozoite Surface Protein 1 of Plasmodium falciparum Strain FVO Expressed in Escherichia coli Protects Aotus nancymai against Challenge with Homologous Erythrocytic-Stage Parasites. The Journal of Immunology 73(1): 287-297.
De Gregorio E, D'Oro U, Wack A. (2009). Immunology of TLR-independent vaccine adjuvants. Curr Opin Immunol 21(3): 339-345.
Garraud O, Diouf A, Holm I, Perraut R, Longacre S. (1999). Immune responses to plamodium falciparum MSP1 Induction of parasite-specific IgG in unsensitized human B cells after in vitro T cell priming with MSP119. Immunology. 97 (3):497-505.
Gilson PR, O'Donnell RA, Nebl T, et al. (2008). MSP119miniproteins can serve as targets for invasion inhibitory antibodies in Plasmodium falciparum provided they contain the correct domains for cell surface trafficking. Molecular Microbiology 68(1): 124-138.
Good MF, Doolan DL. (2010). Malaria Vaccine Design: Immunological Considerations. Immunity 33(4): 555-566.
Hoffman, S.L., Billingsley, P.F., James, E., Richman, A., Loyevsky, M., Li, T.,Chakravarty, S., Gunasekera, A., Chattopadhyay, R., Li, M., et al.(2010).
Development of a metabolically active, non-replicating sporozoite vaccine to prevent Plasmodium falciparum malaria. Hum. Vaccin. 6, 97–106.
Holder AA. (2009). The carboxy-terminus of merozoite surface protein 1: structure, specific antibodies and immunity to malaria. Parasitology 136(12): 1445.
Homologous Erythrocytic-Stage Parasites. Infection and Immunity 73(1): 287-297.
Hui GS, Chang SP, Gibson H, et al. (1991). Influence of adjuvants on the antibody specificity to the Plasmodium falciparum major merozoite surface protein, gp195.
The Journal of Immunology 147(11): 3935-3941.
Irwin W. Sherman.(1998) Malaria: Parasite Biology, Pathogenesis and Protection. ASM Press, Washington DC.
Keller CC, Yamo O, Ouma C et al. (2006). Acquisition of Hemozoin by Monocytes Down-Regulates Interleukin-12 p40 (IL-12p40) Transcripts and Circulating IL-12p70 through an IL-10-Dependent Mechanism: In Vivo and In Vitro Findings in Severe Malarial Anemia. Infection and Immunity 74(9): 5249-5260.
Krieg AM. (1999). Mechanisms and applications of immune stimulatory CpG oligodeoxynucleotides. Biochim Biophys Acta. 1489(1): 107-116.
Li G, Basagoudanavar SH, Gowda DC. (2008). Effect of GPI anchor moiety on the immunogenicity of DNA plasmids encoding the 19-kDa C-terminal portion of Plasmodium falciparum MSP-1. Parasite Immunology 30(6-7): 315-322.
Limbach KJ, Richie TL. (2009). Viral vectors in malaria vaccine development. Parasite Immunology 31(9): 501-519.
Ing R, Segura M, Thawani N, Tam M, Stevenson MM. (2006). Interaction of Mouse Dendritic Cells and Malaria-Infected Erythrocytes: Uptake, Maturation, and Antigen Presentation1. The Journal of Immunology. 176(1):441-50.
Medicine OFT (2001). Application of exoantigens development of Babesia and Plasmodium in vaccine. Tropical Medicine 83(1989): 67-72.
Mya MM, Roy A, Saxena RK, Roy KB. (2002). Isolation, part characterization, immunogenicity, and specificity study of Plasmodium falciparum culture supernatant. Japanese journal of infectious diseases 55(5): 150-156.
O'Dea KP, McKean PG, Harris A, Brown KN. (1995). Processing of the Plasmodium chabaudi chabaudi AS merozoite surface protein 1 in vivo and in vitro. Molecular and Biochemical Parasitology 72: 111-119.
Quin SJ, Seixas EM, Cross CA, et al. (2001). Low CD4+ T cell responses to the C-terminal region of the malaria merozoite surface protein-1 may be attributed to processing within distinct MHC class II pathways. Eur J Immunol. 31(1):72-81.
Quin SJ, Langhorne J. (2001). Different Regions of the Malaria Merozoite Surface Protein 1 of Plasmodium chabaudi Elicit Distinct T-Cell and Antibody IsotypeResponses. Infection and Immunity 69(4): 2245-2251.
Ray K, Rao TS, Sivaraman CA, Basu RN. (1987). Studies on in vitro culture supernatant of P. falciparum. Isolation of antigens for serology. Annals of Tropical Medicine and Parasitology 81(2): 101-103.
Rotman HL, Daly TM, Long CA. (1999). Plasmodium: immunization with carboxyl-terminal regions of MSP1 protects against homologous but not heterologous blood stage parasite challenge. Exp Parasitol. 91(1):78-85
Rudin W, Quesniaux V, Favre N, Bordmann G. (1997). Malaria toxins from P-chabaudi chabaudi AS and P-berghei ANKA cause dyserythropoiesis in C57BL/6 mice. Parasitology 115: 467-474.
Schofield L, Hewitt MC, Evans K, Siomos MA, Seeberger PH. (2002). Synthetic GPI as a candidate antitoxic vaccine in a model of malaria. Nature 418(6899): 785-789.
Seixas E, Cross C, Quin S, Langhorne J (2001). Direct activation of dendritic cells by the malaria parasite, Plasmodium chabaudi chabaudi. Eur J Immunol. 2001 31(10):2970-8
Singh M, Mukherjee P, Narayanasamy K, et al. (2009). Proteome Analysis of Plasmodium falciparum Extracellular Secretory Antigens at Asexual Blood Stages Reveals a Cohort of Proteins with Possible Roles in Immune Modulation and Signaling. Molecular & Cellular Proteomics 8(9): 2102-2118.
Singh S, Miura K, Zhou H, et al. (2006). Immunity to Recombinant Plasmodium falciparum Merozoite Surface Protein 1 (MSP1): Protection in Aotus nancymai Monkeys Strongly Correlates with Anti-MSP1 Antibody Titer and In Vitro Parasite-Inhibitory Activity. Infection and Immunity 74(8): 4573-4580.
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Tamborrini M, Liu X, Mugasa JP, et al. (2010). Synthetic glycosylphosphatidylinos-itol microarray reveals differential antibody levels and fine specificities in children with mild and severe malaria. Bioorganic & Medicinal Chemistry 18(11): 3747-3752.
Triglia T, Healer J, Caruana SR, et al. (2000). AMA play a central role in erythrocyte invision by plasmodium species. Molecular Microbiology 38(4): 706-718.
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Wichmann D, Schwarz RT, Ruppert V, et al. (2007). Plasmodium falciparum glycosylphosphatidylinositol induces limited apoptosis in liver and spleen mouse tissue. Apoptosis 12(6): 1037-1041.
Xu X, Sumita K, Feng C, et al. (2001). Down-Regulation of IL-12 p40 Gene in Plasmodium berghei-Infected Mice. The Journal of Immunology. 167(1):235-41.
Yoshida S, Nagumo H, Yokomine T, et al. (2010). Plasmodium berghei Circumvents Immune Responses Induced by Merozoite Surface Protein 1- and Apical Membrane Antigen 1-Based Vaccines. PLoS One. 5(10):e13727
Awinder K.SOHAL , David. E. Arnot. (1993). PlasmodiumChabaudi: A Short-Term Invitro Culture Method And Its Application To Chloroquine Resistance Testing. Experimental Parasitology 76(3): 314-317
Blackman MJ, Heidrich HG, Donachie S, McBride JS, Holder AA. (1990). A single fragment of amalaria merozoite surface protein remains on the parasite during red cell invasion and is the target of invasion-inhibiting antibodies. Journal of Experimental Medicine 172(1): 379-382.
Blackman MJ, Scott-Finnigan TJ, Shai S, Holder AA. (1994). Antibodies Inhibit the
Protease-mediated Processing of a Malaria Merozoite Surface Protein. Journal of Experimental Medicine 180:389-393.
Bordmann G, Favre N, Rudin W. (1997). Malaria toxins: effects on murine spleen and bone marrow cell proliferation and cytokine production in vitro. Parasitology 115: 475-483.
Boutlis CS,Gowda DC, Naik RS, et al. (2002). Antibodies to Plasmodium falciparum Glycosylphosphatidylinositols: Inverse Association with Tolerance of
Parasitemia in Papua New Guinean Children and Adults. Infection and Immunity 70(9): 5052-5057.
Burns JM Jr, Flaherty PR, Nanavati P, Weidanz WP. (2004). Protection against plasmodium chabaudi Malaria Induced by Immunization with Apical Membrane
Antigen 1 and Merozoite Surface Protein 1 in the Absence of Gamma Interferon or Interleukin-4. Infection and Immunity 72(10): 5605-5612.
Burns JM Jr, Flaherty PR, Romero MM, Weidanz WP. (2003). Immunization against Plasmodium chabaudi malaria using combined formulations of apical membrane antigen-1 and merozoite surface protein-1. Vaccine 21(17-18): 1843-1852.
Bate CA, Taverne J, and Playfair JH (1989). Soluble malarial antigens are toxic and induce the production of tumour necrosis factor in vivo. Immunology.66(4):600-5.
Cheesman S, Tanabe K, Sawai H, et al. (2009). Strain-specific immunity may drive
adaptive polymorphism in the merozoite surface protein 1 of the rodent malaria parasite Plasmodium chabaudi. Infection, Genetics and Evolution 9(2): 248-255.
Crewther PE, Matthew ML, Flegg RH, Anders RF. (1996). Protective Immune Responses to Apical Membrane Antigen 1 of Plasmodium chabaudi Involve Recognition of Strain-Specific Epitopes. Infect Immun. 64(8):3310-7.
Daly TM and Long CA (1993). A recombinant 15-Kilodalton carboxyl-terminal fragment of Plasmodium yoelii 17XL merozoite surface protein linduces a protective immune response in mice. Infection and Immunity 61(6): 2462-2467.
Daly TM, Long CA. (1995). Humoral response to a carboxyl-terminal region of the merozoite surface protein-1 plays a predominant role in controlling blood-stage infection in rodent malaria. The Journal of Immunology 155: 236-243.
Darko CA, Angov E, Collins WE, et al. (2004). The Clinical-Grade 42-Kilodalton Fragment of Merozoite Surface Protein 1 of Plasmodium falciparum Strain FVO Expressed in Escherichia coli Protects Aotus nancymai against Challenge with Homologous Erythrocytic-Stage Parasites. The Journal of Immunology 73(1): 287-297.
De Gregorio E, D'Oro U, Wack A. (2009). Immunology of TLR-independent vaccine adjuvants. Curr Opin Immunol 21(3): 339-345.
Garraud O, Diouf A, Holm I, Perraut R, Longacre S. (1999). Immune responses to plamodium falciparum MSP1 Induction of parasite-specific IgG in unsensitized human B cells after in vitro T cell priming with MSP119. Immunology. 97 (3):497-505.
Gilson PR, O'Donnell RA, Nebl T, et al. (2008). MSP119miniproteins can serve as targets for invasion inhibitory antibodies in Plasmodium falciparum provided they contain the correct domains for cell surface trafficking. Molecular Microbiology 68(1): 124-138.
Good MF, Doolan DL. (2010). Malaria Vaccine Design: Immunological Considerations. Immunity 33(4): 555-566.
Hoffman, S.L., Billingsley, P.F., James, E., Richman, A., Loyevsky, M., Li, T.,Chakravarty, S., Gunasekera, A., Chattopadhyay, R., Li, M., et al.(2010).
Development of a metabolically active, non-replicating sporozoite vaccine to prevent Plasmodium falciparum malaria. Hum. Vaccin. 6, 97–106.
Holder AA. (2009). The carboxy-terminus of merozoite surface protein 1: structure, specific antibodies and immunity to malaria. Parasitology 136(12): 1445.
Homologous Erythrocytic-Stage Parasites. Infection and Immunity 73(1): 287-297.
Hui GS, Chang SP, Gibson H, et al. (1991). Influence of adjuvants on the antibody specificity to the Plasmodium falciparum major merozoite surface protein, gp195.
The Journal of Immunology 147(11): 3935-3941.
Irwin W. Sherman.(1998) Malaria: Parasite Biology, Pathogenesis and Protection. ASM Press, Washington DC.
Keller CC, Yamo O, Ouma C et al. (2006). Acquisition of Hemozoin by Monocytes Down-Regulates Interleukin-12 p40 (IL-12p40) Transcripts and Circulating IL-12p70 through an IL-10-Dependent Mechanism: In Vivo and In Vitro Findings in Severe Malarial Anemia. Infection and Immunity 74(9): 5249-5260.
Krieg AM. (1999). Mechanisms and applications of immune stimulatory CpG oligodeoxynucleotides. Biochim Biophys Acta. 1489(1): 107-116.
Li G, Basagoudanavar SH, Gowda DC. (2008). Effect of GPI anchor moiety on the immunogenicity of DNA plasmids encoding the 19-kDa C-terminal portion of Plasmodium falciparum MSP-1. Parasite Immunology 30(6-7): 315-322.
Limbach KJ, Richie TL. (2009). Viral vectors in malaria vaccine development. Parasite Immunology 31(9): 501-519.
Ing R, Segura M, Thawani N, Tam M, Stevenson MM. (2006). Interaction of Mouse Dendritic Cells and Malaria-Infected Erythrocytes: Uptake, Maturation, and Antigen Presentation1. The Journal of Immunology. 176(1):441-50.
Medicine OFT (2001). Application of exoantigens development of Babesia and Plasmodium in vaccine. Tropical Medicine 83(1989): 67-72.
Mya MM, Roy A, Saxena RK, Roy KB. (2002). Isolation, part characterization, immunogenicity, and specificity study of Plasmodium falciparum culture supernatant. Japanese journal of infectious diseases 55(5): 150-156.
O'Dea KP, McKean PG, Harris A, Brown KN. (1995). Processing of the Plasmodium chabaudi chabaudi AS merozoite surface protein 1 in vivo and in vitro. Molecular and Biochemical Parasitology 72: 111-119.
Quin SJ, Seixas EM, Cross CA, et al. (2001). Low CD4+ T cell responses to the C-terminal region of the malaria merozoite surface protein-1 may be attributed to processing within distinct MHC class II pathways. Eur J Immunol. 31(1):72-81.
Quin SJ, Langhorne J. (2001). Different Regions of the Malaria Merozoite Surface Protein 1 of Plasmodium chabaudi Elicit Distinct T-Cell and Antibody IsotypeResponses. Infection and Immunity 69(4): 2245-2251.
Ray K, Rao TS, Sivaraman CA, Basu RN. (1987). Studies on in vitro culture supernatant of P. falciparum. Isolation of antigens for serology. Annals of Tropical Medicine and Parasitology 81(2): 101-103.
Rotman HL, Daly TM, Long CA. (1999). Plasmodium: immunization with carboxyl-terminal regions of MSP1 protects against homologous but not heterologous blood stage parasite challenge. Exp Parasitol. 91(1):78-85
Rudin W, Quesniaux V, Favre N, Bordmann G. (1997). Malaria toxins from P-chabaudi chabaudi AS and P-berghei ANKA cause dyserythropoiesis in C57BL/6 mice. Parasitology 115: 467-474.
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