Abrogation of resistance to the reinduction of experimental allergic encephalomyelitis by pertussigen

Experimental allergic encephalomyelitis is an autoimmune disease initiated by an injection of myelin basic protein in complete Freund's adjuvant. Lewis rats which have recovered from the initial episode of hindquarter paralysis are resistant for at least 6 months to disease reinduction by basic protein-complete Freund's adjuvant, although specific antigen-reactive cells are detectable in convalescent rats. Resistance cannot be attributed to the activity of the adjuvant alone. In contrast, clinical disease could be reinduced by a secondary challenge with spinal cord homogenate and pertussigen (“lymphocytosis promoting factor” of Bordetella pertussis). Disease could also be reinduced by a simultaneous secondary challenge with basic protein-complete Freund's adjuvant along with pertussigen. Vascular permeability increases in the spinal cord paralleled disease induction or reinduction. No definite conclusions can be drawn concerning the mechanism by which pertussigen promotes disease reinduction in convalescent rats.     

Evaluation of the adjuvant activity of naloxone,an opioid receptor antagonist,in combination with heat-killed Listeria monocytogenes vaccine

We have previously demonstrated the adjuvant activity of naloxone (NLX), a general opioid antagonist, using a DNA vaccine for herpes simplex virus type 1. Here, the adjuvant activity of NLX has been evaluated using a heat-killed Listeria monocytogenes (HKLM) vaccine as a model for general immunization against intracellular bacteria. BALB/c mice were divided into three groups: the Vac group received the HKLM vaccine alone; the NLX–Vac group received the HKLM vaccine in combination with the adjuvant NLX; and the control group received phosphate buffered saline (PBS). Our results indicate that the administration of NLX as an adjuvant enhances the ability of the HKLM vaccine to increase lymphocyte proliferation, delayed type hypersensitivity, and skewing of the immune response toward a T-helper 1 (Th1) pattern. Additionally, combination of NLX with the HKLM vaccine improves protective immunity against L. monocytogenes. In conclusion, administration of NLX as an adjuvant for the HKLM vaccine can enhance cell-mediated immunity and shift the immune response to Th1.     

Preparation and Effect of Different Adjuvants on the Immunogenic Activity of Mycobacterial Ribosomal Fraction

Several emulsified and two nonemulsified incomplete adjuvants were examined for their adjuvant activity by use of mycobacterial ribosomal fractions as a substrate. A good adjuvant is defined as one which produces a high immunological response with the ribosomal fraction in mice to infection with virulent tubercle bacilli. Freund's incomplete adjuvant, consisting of Aquaphor and heavy mineral oil, and Arlacel A plus hexadecane were the best adjuvants tested. Aquaphor plus light mineral oil and Arlacel A plus 7-n-hexyloctadecane were not quite as effective. Peanut oil was not satisfactory when emulsified with either Aquaphor or Arlacel A. A moderate degree of immunity was produced in mice vaccinated with ribosomal fraction mixed with aluminum hydroxide gel. Sodium alginate mixed with ribosomal fraction produced a low degree of immunity only with the highest vaccinating dose. It was found that the effectiveness of the emulsified type of adjuvant depended upon the method of preparation. Careful standardization of technique to produce uniform and complete emulsification was essential for maximal adjuvant activity using minimal vaccinating doses. A rapid and practical method of preparing emulsified adjuvants is given. The mode of action of incomplete adjuvants as employed in these experiments is discussed, and it is thought that they acted primarily by protecting the ribosomes from being inactivated by host ribonuclease before they were engulfed by the macrophages.     

The effect of a mixture of bacterial ribosomes and membrane fractions of Klebsiella pneumoniae on the development of a transplanted epithelial cancer in rats]

An association of bacterial ribosomes and cell-wall of Klebsiella pneumoniae was shown to reduce the incidence of an epidermoid carcinoma in Sprague-Dawley rats when administered subcutaneously prior the tumoral graft. Mononuclear cells accumulate around the tumor. This association was considered as a non specific adjuvant stimulating the host's intrinsic immunity to tumor antigens.     

霍乱毒素佐剂的研究进展

霍乱毒素（CT）是霍乱弧菌分泌的一种不耐热肠毒素,具有很强的免疫原性和佐剂活性,是当今研究得最多且最深入的粘膜免疫佐剂之一,CT本身有很强的毒副作用,而一定的毒性又似乎是发挥佐剂作用所必须的。通过各种改造,使之具备优良的佐剂活性而没有显的毒副作用是当前研究的主要目标。本从CT作为佐剂的作用机理出发,概述当前对其进行改造的几种研究方向。     

Adenoviral-mediated interleukin-18 expression in mesenchymal stem cells effectively suppresses the growth of glioma in rats

Glioma is the most common primary intracranial malignant tumor. Despite advances in surgical techniques and adjuvant radio- and chemotherapies, the prognosis for patients with glioma remains poor. We have explored the effects of using genetically modified mesenchymal stem cells (MSCs) to treat malignant glioma in rats. Mesenchymal stem cells isolated from Sprague-Dawley rats can directly suppress the growth of C6 cells in vitro. MSCs transplanted intratumorally can also significantly inhibit the growth of glioma and prolong survival in C6 glioma-bearing models. MSCs producing Interleukin-18 infected by adenoviral vector inhibited glioma growth and prolonged the survival of glioma-bearing rats. Transplantation of IL-18 secreting MSCs was associated with enhanced T cell infiltration and long-term anti-tumor immunity. Thus, IL-18 may be an effective adoptive immunotherapy for malignant glioma. When used in conjunction with MSCs as targeting vehicles in vivo, IL-18 may offer a promising new treatment option for malignant glioma.     

增强恶性疟原虫DNA疫苗免疫反应的研究

构建了含有恶性疟原虫抗原基因 ( AWTE)及白介素 2基因的重组质粒 p CMV- AWTE以及p CMV- IL2、p CMV- IL2 - AWTE、p RSV- AWTE。将纯化的质粒混合后免疫小鼠 ,3次免疫后比较其诱导机体产生的免疫应答的水平 ,发现 IL- 2可以明显地提高机体的细胞免疫 ,而对体液免疫的影响甚微。麻醉剂、蔗糖、免疫剂量等因素也可以不同程度地提高机体的免疫应答水平 ,RSV启动子与 CMV启动子对免疫应答水平无明显的影响     

Histochemical changes of substance P, FRAP, serotonin and succinic dehydrogenase in the spinal cord of rats with adjuvant arthritis

Various histochemical changes were found in spinal segments L4-L5 of rats with adjuvant arthritis, predominantly 30 days after inoculation. A slight to marked increase of substance P immunoreactivity occurred in laminae I, II and X. FRAP activity was enhanced in lamina II. Serotonin immunoreactivity was heavier in laminae I, VIII and IX in a few animals. The intensity of the histoenzymological reaction for succinic dehydrogenase increased in certain laminae VIII and X neurons. At day 15 of the disease the increase of substance P and FRAP activities was chiefly restricted to the medial portion of the superficial dorsal horn. There was a significant positive correlation between the scratching behaviour of arthritic rats and the substance P immunoreactivity in laminae X and I. If one accepts that scratching is pain-related, the data are consistent with a possible role of substance P in the chronic pain associated with adjuvant arthritis. They leave undetermined the significance of the other histochemical changes.     

Autoimmune effector cells. IV. Induction of experimental allergic encephalomyelitis in Lewis rats without adjuvant

Experimental autoimmune encephalomyelitis (EAE) was induced in Lewis rats without the aid of adjuvant. Radioresistant cells were activated from spleens of nonimmune donor rats by in vitro culture with myelin basic protein (BP). After adoptive transfer, these cells recruited EAE effector cells in normal syngeneic recipients, as demonstrated after transfer to secondary hosts. The induction of EAE without adjuvant may lead to a better understanding of the mechanisms of autoimmune disease induction.     

Regulation of experimental allergic encephalomyelitis. II. Appearance of suppressor cells during the remission phase of the disease

Lewis rats are susceptible to experimental autoimmune encephalomyelitis (EAE). Most rats recover from paralysis and are subsequently resistant to the disease. In an adoptive transfer system, we found that lymph node cells (LNC) from rats that had recovered from EAE protect syngeneic recipients from the disease when the latter are challenged with encephalitogenic myelin basic protein and adjuvant after receiving donor cells. Suppression is antigen-specific and requires viable LNC. In contrast to the suppressor cells we previously studied in tolerized rats, which were nonadherent T lymphocytes, the suppressor cells found in rats that have recovered from EAE adhere to glass wool. However, they are not retained on Sephadex G-10 columns to which macrophages adhere. Suppressor activity is enriched in the nylon wool-adherent LNC population (which consists of approximately 80% Ig+ cells). Our findings suggest that activation of adherent suppressor cells may be implicated in recovery from EAE. These may be adherent T cells, or B cells that produce anti-BP blocking antibodies.     

Systemic IL-1 and adjuvant treatment of an experimental tumor

Local adjuvant therapy of weakly immunogenic tumors protects against primary tumor challenge. However, this form of therapy does not produce long-lasting immunity to the tumor. In this study, local adjuvant therapy combined with systemic IL-1 administration produced not only primary tumor protection, but also long lasting immunity to the tumor. IL-1 and adjuvant protected animals resisted rechallenge with tumor as much as 180 days after initial tumor administration. Resistance to tumor rechallenge was IL-1 dose dependent. IL-1 and adjuvant protected animals also exhibited delayed type hypersensitivity reactions which were tumor-specific. Splenic and lymph node cell populations from IL-1 and adjuvant protected animals mounted tumor-specific lymphoproliferative responses. No such responses were observed in animals which had been administered either IL-1 or adjuvant alone. These results demonstrate that systemic IL-1 functions to augment specific immune protection when administered in conjunction with local adjuvant, resulting in long-lasting tumor immunity.     

Pertussis toxin-induced cytokine differentiation and clonal expansion of T cells is mediated predominantly via costimulation

Pertussis toxin (PTX) has potent immunologic adjuvant activity in vivo and concomitantly enhances both T helper type (Th1) and Th2 cytokine responses. The PTX-induced enhancement of Th1 and Th2 immunity is mediated via the activation of antigen presenting cells (APCs), but the underlying mechanism is not known. Here we asked whether the adjuvant activity of PTX on T cell immunity was mediated by cytokines and/or costimulatory signals. The results show that in vivo blockade of CD28-CD80/86 costimulation essentially abrogated PTX-mediated enhancement of antigen-specific Th1 and Th2 responses. Blockade of CD40L-CD40 interactions was less efficient in inhibiting PTX-mediated enhancement of Th1 and Th2 responses. In contrast, the adjuvant activity of PTX was not mediated via cytokines, because neither Th1 nor Th2 responses were substantially impaired in mice deficient for IL-12, IFN-gamma, IL-4, IL-5, or IL-6. Collectively, the data suggest that PTX mediates its adjuvant effects on T cell cytokine differentiation and clonal expansion via the modulation of costimulatory molecules on APCs. Understanding the costimulatory pathways targeted by PTX could lead to the design of novel adjuvants that selectively induce Th1 or Th2 immunity.     

Acute stressor exposure facilitates innate immunity more in physically active than in sedentary rats

Most previous stress-immune research focused on the immunosuppressive effects of stress on acquired immunity. More recently, it has become clear that acute stressor exposure can potentiate innate, as well as suppress acquired, immunity. For example, acute stress improves recovery from bacterial inflammation, a classic in vivo measure of innate immunity. The previous work was done in sedentary organisms. Physical activity status can modulate the impact of stress on immune function. The following studies tested the hypothesis that the effect of stress on inflammation after subcutaneous challenge with bacteria (Escherichia coli) is facilitated by physical activity. The results were that sedentary, stressed rats resolved their inflammation 1-2 days faster and have increased circulating neutrophils compared with their nonstressed, sedentary counterparts. In contrast, physically active, stressed rats resolve their inflammation 3-4 days faster and have increased circulating and inflammatory site neutrophils compared with their nonstressed counterparts. Importantly, the beneficial impact of stress on inflammation recovery and neutrophil migration was greater in the physically active, than sedentary, stressed rats. Thus physical activity status facilitates the positive effect of acute stress on innate immunity.     

Assessment of plasma leukotriene and prostaglandin levels during adjuvant arthritis and kaolin-induced paw oedema in rats

Plasma levels of some arachidonic acid metabolites were investigated in acute and chronic models of inflammation in rats. As a model of chronic inflammation, adjuvant arthritis in rats induced by the injection of Freund's complete adjuvant, and as an acute model for inflammation, kaolin-induced paw oedama were used. Plasma leukotriene(LT) C4-like and prostaglandin(PG) E2-like activities were quantitated by bioassay in guinea-pig ileum and rat stomach fundus respectively. In the course of adjuvant arthritis, plasma levels of LTC4- and PGEi2-like activities were increased. Plasma LTC4-like activity reached a maximum within 3 weeks, while PGE2-like activity reached a maximum 10 days after adjuvant injection. In the early phase of adjuvant arthritis, levels of both LTC4- and PGE2-like activities were found to be low but both activities were increased in the late phase of inflammation.     

IL-2与猪细小病毒VP2基因双表达载体的构建及免疫原性的研究

将白细胞介素-2基因和猪细小病毒VP2基因主要抗原区克隆至pCI-neo真核表达载体中,构建了pCIneo-IL2-VP2重组质粒,用脂质体将其转染到PK-15细胞中,利用免疫荧光方法检测在体外表达情况。并以小鼠为动物模型,将pCIneo-IL2-VP2重组质粒、对照组pCI-neo和猪细小病毒活疫苗通过肌肉注射进行免疫,检测免疫小鼠的淋巴细胞转化功能,特异性CTL杀伤活性和血清抗体滴度。结果显示,pCIneo-IL2-VP2在体外能够诱导PK-15细胞表达VP2蛋白,小鼠注射pCIneo-IL2-VP2质粒1周后能够诱导机体产生抗体,4周时达到峰值,与活疫苗对照组产生的抗体滴度、诱导T淋巴细胞增殖和诱导强的细胞毒性基本一致。试验表明,构建的pCIneo-IL2-VP2能够有效诱导机体产生体液免疫和细胞免疫。     

Plasmodium berghei: Immunogenic enhancement of antigen by adjuvant addition

Vaccines consisting of soluble Plasmodium berghei antigen in conjunction with a variety of adjuvants were injected into weanling white rats. Protective immunity, as evidenced by a lower mortality rate, reduced parasitemia and shortened course of infection, was induced by antigen in combination with the following adjuvants: saponin, hexylamine, Bordetella pertussis vaccine, levamisole, and polyinosinic-polycytidylic acid (poly I:C). Soluble antigen alone or combined with Freund's complete adjuvant, bacterial cndotoxin, vitamin A, polyadenylic-polyuredelic acid (poly A:U) failed to induce any significant degree of protective immunity.     

The Extracellular Domain of Myelin Oligodendrocyte Glycoprotein Elicits Atypical Experimental Autoimmune Encephalomyelitis in Rat and Macaque Species

Atypical models of experimental autoimmune encephalomyelitis (EAE) are advantageous in that the heterogeneity of clinical signs appears more reflective of those in multiple sclerosis (MS). Conversely, models of classical EAE feature stereotypic progression of an ascending flaccid paralysis that is not a characteristic of MS. The study of atypical EAE however has been limited due to the relative lack of suitable models that feature reliable disease incidence and severity, excepting mice deficient in gamma-interferon signaling pathways. In this study, atypical EAE was induced in Lewis rats, and a related approach was effective for induction of an unusual neurologic syndrome in a cynomolgus macaque. Lewis rats were immunized with the rat immunoglobulin variable (IgV)-related extracellular domain of myelin oligodendrocyte glycoprotein (IgV-MOG) in complete Freund’s adjuvant (CFA) followed by one or more injections of rat IgV-MOG in incomplete Freund’s adjuvant (IFA). The resulting disease was marked by torticollis, unilateral rigid paralysis, forelimb weakness, and high titers of anti-MOG antibody against conformational epitopes of MOG, as well as other signs of atypical EAE. A similar strategy elicited a distinct atypical form of EAE in a cynomolgus macaque. By day 36 in the monkey, titers of IgG against conformational epitopes of extracellular MOG were evident, and on day 201, the macaque had an abrupt onset of an unusual form of EAE that included a pronounced arousal-dependent, transient myotonia. The disease persisted for 6–7 weeks and was marked by a gradual, consistent improvement and an eventual full recovery without recurrence. These data indicate that one or more boosters of IgV-MOG in IFA represent a key variable for induction of atypical or unusual forms of EAE in rat and Macaca species. These studies also reveal a close correlation between humoral immunity against conformational epitopes of MOG, extended confluent demyelinating plaques in spinal cord and brainstem, and atypical disease induction.     

The effect of adjuvant and microbial challenge on the expression of antimicrobial polypeptides in channel catfish (Ictalurus punctatus)

While antimicrobial polypeptides (AMPPs) are increasingly recognized as one of the most important components of innate immunity, there is very little information in vertebrates that documents their upregulation to levels that are microbicidal in vivo. Here we demonstrate that intraperitoneal injection of either Freund's complete adjuvant (FCA) or live Tetrahymena pyriformis (a parasitic ciliate) upregulated AMPP expression in channel catfish skin. FCA induced significant upregulation of total antibacterial activity, anti-Edwardsiella ictaluri activity (the fraction of antibacterial activity active against E. ictaluri), and HLP-1 (the major AMPP in channel catfish skin). Tetrahymena induced a similar upregulation, except that HLP-1 was not significantly induced and the response appeared to be more transient than FCA immunostimulation. AMPP levels were increased up to five-fold higher than resting levels and levels expressed were well within concentrations known to be inhibitory to many important pathogens in vitro. These results provide encouragement that AMPP upregulation may be a promising tool in aquaculture for enhancing the resistance of fish to disease.     

Immunoregulation in experimental interstitial nephritis: immunization with renal tubular antigen in incomplete Freund's adjuvant induces major histocompatibility complex-restricted, OX8+ suppressor T cells which are antigen-specific and inhibit the expression of disease

We utilized a model of experimental interstitial nephritis induced by renal tubular antigen in complete Freund's adjuvant to examine a mechanism of immunologic tolerance produced by priming immunization with tubular antigen in incomplete Freund's adjuvant. Brown Norway rats primed with tubular antigen in incomplete adjuvant do not develop significant nephritis after challenge with antigen in complete adjuvant, and this tolerance can be transferred to naive recipients with donor T cells. These T cells also specifically suppress a delayed-type hypersensitivity response to soluble tubular antigen in recipients immunized to produce disease. This suppression is MHC-restricted and is mediated by OX8+ T cells which bind antigen and bear idiotypes cross-reactive with those on antibodies eluted from the tubular basement membrane. Despite the suppression of histologic disease, tolerized animals were able to produce significant titers of antibodies to tubular basement membrane. Our findings demonstrate an additional strategy for altering the natural history of immune-mediated renal disease, and further refine the characterization of the suppressive effect produced by incomplete Freund's adjuvant.     

Dendritic cell‐targeting DNA‐based nasal adjuvants for protective mucosal immunity to Streptococcus pneumoniae

To develop safe vaccines for inducing mucosal immunity to major pulmonary bacterial infections, appropriate vaccine antigens (Ags), delivery systems and nontoxic molecular adjuvants must be considered. Such vaccine constructs can induce Ag‐specific immune responses that protect against mucosal infections. In particular, it has been shown that simply mixing the adjuvant with the bacterial Ag is a relatively easy means of constructing adjuvant‐based mucosal vaccine preparations; the resulting vaccines can elicit protective immunity. DNA‐based nasal adjuvants targeting mucosal DCs have been studied in order to induce Ag‐specific mucosal and systemic immune responses that provide essential protection against microbial pathogens that invade mucosal surfaces. In this review, initially a plasmid encoding the cDNA of Flt3 ligand (pFL), a molecule that is a growth factor for DCs, as an effective adjuvant for mucosal immunity to pneumococcal infections, is introduced. Next, the potential of adding unmethylated CpG oligodeoxynucleotide and pFL together with a pneumococcal Ag to induce protection from pneumococcal infections is discussed. Pneumococcal surface protein A has been used as vaccine for restoring mucosal immunity in older persons. Further, our nasal pFL adjuvant system with phosphorylcholine‐keyhole limpet hemocyanin (PC‐KLH) has also been used in pneumococcal vaccine development to induce complete protection from nasal carriage by Streptococcus pneumoniae . Finally, the possibility that anti‐PC antibodies induced by nasal delivery of pFL plus PC‐KLH may play a protective role in prevention of atherogenesis and thus block subsequent development of cardiovascular disease is discussed.