Passively transferable protection against Schistosoma japonicum induced in the mouse by multiple vaccination with attenuated larvae: the development of immunity, antibody isotype responses and antigen recognition

Vaccination of mice with attenuated S. japonicum cercariae induces protection against secondary infection which can be transferred to naive mice with serum (VMS). The presence of antibody does not per se impart protection as serum from mice carrying non-attenuated infections (CIS), contains high levels of specific antibody, but confers no protection. Here we describe the increased protection transferred (20 to 68%) with increased number of vaccinations (one to five) given to the donors, and its decline with time after the final vaccination. We also describe the development of IgM, IgA, IgE, total IgG and IgG subclass responses in VMS, giving different levels of protection and CIS, directed against sodium periodate-sensitive and -resistant epitopes in ‘skin-stage’, ‘lung-stage’and ‘liver-stage’schistosomula, adult worms and eggs. In addition, antibody affinity maturation, development of S. japonicum species-specific responses, and vaccination-specific responses were examined. No response developed in parallel with serum-mediated immunity, suggesting immunity may be due to responses against individual antigens. Preliminary examination of antigens recognized in Western blot showed that two schistosomal membrane antigens, of 13 and 40 kDa, were recognized by VMS from mice vaccinated five times (68% protection), but not by twice vaccinated VMS (27% protection). Neither antigen was recognized by non-protective CIS.     

中老年人膳食和体液免疫水平的调查

作者调查了１６１例（男：９８，女：６３）中老年人的营养素摄入量、血浆蛋白及体液免疫水平。结果：该人群的大部分人热能的摄入量达ＲＤＡ值；膳食蛋白质、维生素Ａ、Ｂ２、Ｃ、锌和铁的摄入量较低；脂肪摄入量按热能比高于３０％者约占３０％；血浆总蛋白、球蛋白水平较低，尤其是女性；免疫球蛋白ＩｇＡ偏低，ＩｇＧ和ＩｇＭ偏高。     

维生素E对烧伤小鼠免疫功能改善及其机制

本实验研究了维生素Ｅ（ＶＥ）改善烧伤后免疫功能的作用，并对其作用机制进行了探讨。结果显示，小鼠１１％～１２％总体表面积（ＴＢＳＡ）全层皮肤烧伤后血、肝、脾中过氧化脂质（ＬＰＯ）水平升高、谷胱甘肽（ＧＳＨ）含量下降，淋巴细胞增殖反应、白介素一２（ＩＬ一２）生成、空斑形成细胞（ＩＪＦＣ）形成及迟发型超敏反应（ＤＴＨ）均处于抑制状态。投予ＶＥ后可防止烧伤动物体内ＬＰＯ水平、ＧＳＨ含量明显变化，免疫功能受抑制的程度也明显小于未投予组。以超氧化物歧化酶（ＳＯＤ）处理的作用与ＶＥ相同。体外实验显示，过氧化亚油酸可抑制淋巴细胞增殖反应以及ＩＬ一２产生、诱发淋巴细胞脂质过氧化、降低淋巴细胞内ＧＳＨ含量。淋巴细胞上述功能的抑制与ＬＰＯ水平密切相关；加入ＶＥ可抑制过氧化亚油酸对淋巴细胞的上述作用。提示ＶＥ可改善烧伤后免疫功能，其机制可能是通过抗氧化作用而发挥的。     

Research highlights from the literature

Genes influencing the autonomic nervous system continue as a focus of research. Recent publications applied different methods to identify genes influencing autonomic cardiovascular regulation in humans. Two reports relied on a candidate gene approach. Common genetic polymorphisms in the promoter region of the tyrosine hydroxylase gene were shown to influence catecholamine synthesis and blood pressure. The same group tested the hypothesis that the GTP cyclohydrolase 1 (GCH1) gene influences catecholamine excretion and cardiovascular regulation. GCH1 affects tyrosine hydroxylase function indirectly. The authors concluded that the GCH1 gene may influence cardiovascular autonomic regulation through changes in nitric oxide production rather than a change in tyrosine hydroxylase activity. The third genetic study used a single nucleotide polymorphism chip to analyze 100,000 genetic polymorphisms scattered throughout the genome in participants of the Framingham study. The authors identified several polymorphisms that may influence QT interval duration, heart rate, and heart rate variability. The respective genes have not been identified with certainty. Another study suggested that catecholamines may be released from phagocytes and regulate pulmonary inflammation through alpha-2 adrenoreceptor activation in an autocrine or paracrine fashion.     

Changes in activity of some mechanisms of specific and nonspecific immunity in vitamin B1 deficiency

The effect of thiamine deficiency on the immune response and activity of certain mechanisms of natural immunity was studied in adult rats. Thiamine deficiency was simulated experimentally by a single injection of hydroxythiamine, a vitamin B₁ antagonist. Administration of hydroxythiamine caused a marked decrease in complement activity, phagocytic activity of the peripheral blood leukocytes, bactericidal activity of the serum, and antibody production in response to immunization with sheep's red blood cells. Conversely, lysozyme activity increased. In vitamin B₁ deficiency the intensity of incorporation of [¹⁴C]leucine into liver protein synthesis was reduced.Department of Pathological Physiology, N. I. Sechenov First Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR G. V. Vygodchikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 7, pp. 60–62, July, 1979.     

Qualitative difference between the cytotoxic T lymphocyte responses to melanocyte antigens in melanoma and vitiligo

Vitiligo is a skin disorder characterized by depigmented macules secondary to melanocyte loss. An unusual facet is its relation to melanoma: cytotoxic T lymphocytes directed to melanocyte antigens are found in both conditions and imply a breakdown of tolerance, yet the resulting immune reaction is the opposite. The mechanisms at the basis of these opposite effects are not known. Here, we performed a direct comparison of whole melanocyte-specific T cell populations in the two diseases. We demonstrate that neither precursor frequencies of Melan-A/MART-1-specific T lymphocytes nor their status of activation differ significantly. However, by using a tetramer-based T cell receptor down-regulation assay, we documented a higher affinity of vitiligo T cells. We calculated that the peptide concentration required for 50% of maximal receptor down-regulation differed by 6.5-fold between the two diseases. Moreover, only vitiligo T cells were capable of efficient receptor down-regulation and IFN-gamma production in response to HLA-matched melanoma cells, suggesting that this difference in receptor affinity is physiologically relevant. The differences in receptor affinity and tumor reactivity were confirmed by analyzing Melan-A/MART-1-specific clones established from the two diseases. Our results suggest that the quality, and not the quantity, of the melanocyte-specific cytotoxic responses differs between the two pathologies.     

天然免疫模式识别途径:胞外识别与胞内识别

天然免疫系统通常籍模式识别受体识别病原体相关分子模式。取决于感染的性质,模式识别受体通过细胞外 或细胞内途径识别病原体,并传导相应的信号,激活宿主防御应答,消灭入侵病原体。     

Rational approaches to immune regulation

Our studies are mainly focused on developing strategies of immune regulation. In the case of infectious and neoplastic disease, our approach is to upregulate cell-mediated immunity to viral of tumor antigens using an intracellular bacterium as a vector for targeting these antigens to the major histocompatibility complex (MHC) class I and class II pathways of antigen processing, in addition to exploiting the adjuvant properties of the vector to stimulate innate immunity. In the area of autoimmunity, we are attempting to downregulate the immune response by specific immune intervention directed against autoreactive T cells. In these studies we use murine models for multiple sclerosis. Our approach is to use both rationally designed T cell receptor (TCR) peptide analogs and recombinant viral vectors that express TCR components to regulate the disease.     

Induction and expression of protective T cells during Mycobacterium avium infections in mice.

Mycobacterium avium is an opportunistic pathogen that infects individuals suffering from chronic lung disease or immunocompromised patients such as AIDS patients. Here we show that a highly virulent isolate of M. avium proliferated as extensively in T cell deficient as in immunocompetent mice. T cell deficient mice allowed a progressive growth of a less virulent AIDS-derived isolate of M. avium while immunocompetent mice arrested the growth of this isolate. Adoptive transfer of T cell enriched spleen cells between congenic strains of mice differing at the Bcg/Ity/Lsh locus showed that only naturally resistant BALB/c.Bcgr (C.D2) mice infected with the highly virulent strain of M. avium or the naturally susceptible BALB/c mice infected with the lower virulence isolate developed protective T cells and that these cells only mediated protection when transferred to naturally susceptible, but not to naturally resistant, mice. Both strains of M. avium proliferated in bone marrow-derived macrophages cultured in vitro and they were both susceptible to the bacteriostatic effects induced in the macrophages by crude lymphokines produced by concanavalin A-stimulated spleen cells.     

Rational approaches to immune regulation

Our laboratory is interested in the properties of proteins that render them immunogenic, and how such immunogenicity may be modulated in vivo. We are attempting to enhance the immune response in the design of more effective vaccines against viral diseases, such as HIV, and against tumor antigens expressed on breast, ovarian, and cervical cancer and B cell lymphomas. Our main approach is to use a facultative intracellular bacterium, Listeria monocytogenes, which has the unusual ability to live and grow in the cytoplasm of the cell and is thus an excellent vector for targeting passenger antigens to the major histocompatibility complex (MHC) class I pathway of antigen processing with the generation of authentic cytotoxic T lymphocytes (CTL) epitopes. In the field of tumor immunotherapy, we are also developing nonliving vaccine vectors for tumor antigens.