Induction of host gene expression following infection of chicken embryo fibroblasts with oncogenic Marek's disease virus

Microarrays containing 1,126 nonredundant cDNAs selected from a chicken activated T-cell expressed sequence tag database (http://chickest.udel.edu) were used to examine changes in host cell gene expression that accompany infection of chicken embryo fibroblasts (CEF) with Marek's disease virus (MDV). Host genes that were reproducibly induced by infection of CEF with the oncogenic RB1B strain of MDV included macrophage inflammatory protein, interferon response factor 1, interferon-inducible protein, quiescence-specific protein, thymic shared antigen 1, major histocompatibility complex (MHC) class I, MHC class II, beta(2)-microglobulin, clusterin, interleukin-13 receptor alpha chain, ovotransferrin, a serine/threonine kinase, and avian leukosis virus subgroup J glycoprotein.     

A functional MicroRNA-155 ortholog encoded by the oncogenic Marek's disease virus

Kaposi's sarcoma-associated herpesvirus-encoded microRNA (miRNA) MiR-K12-11 was recently shown to be a functional ortholog of miR-155, a miRNA that plays a major role in lymphoid malignancies and the modulation of immune responses. Here we show that miR-M4, encoded by the highly oncogenic Marek's disease virus of chickens, shares common targets with miR-155 and thus is also a functional ortholog of miR-155, the first one identified in an alphaherpesvirus. The observation that two distinct oncogenic herpesviruses associated with distinct types of lymphomas in different species encode functional miR-155 orthologs suggested the importance of this miRNA in regulatory pathways and the biology of lymphomagenesis.     

In vivo and in vitro measurement of cell mediated immunity in Marek's disease: role of reticuloendothelial system

Dinitrofluorobenzene (DNFB) contact-sensitivity test and leucocyte adherence inhibition (LAI) test were performed in this study as in vivo and in vitro tests to measure the cell-mediated immunity (CMI) in chickens subjected to stimulation of reticuloendothelial (RE) system, depletion of RE system and other experimental groups after being challenged with Marek's disease (MD) virus. It was found that CMI was lower in the birds with depleted RE system and infected control birds, whereas CMI was higher in the birds with activated RE system and vaccinated birds as revealed by DNFB contact-sensitivity test. In cases of LAI test, the number of LAI-positive birds were highest in the chicks with depleted RE system particularly in 3rd and 4th month of age, when the incidence of MD was also maximum.     

阿尔茨海默病核酸疫苗的构建及诱导体液免疫反应的初步研究

近年,内源性蛋白主动免疫预防和治疗阿尔茨海默病(AD)的策略成为AD研究领域的热点,并获得迅猛发展。构建了以β-片层结构的淀粉样蛋白(AB)及其可溶性与病理性突变体为抗原基因的DNA疫苗用于免疫小鼠,经过对免疫方案的探索和调整,结果能够打破其自身耐受,在外周血中诱发出较高滴度的抗-AB抗体。初步探讨了诱导体液免疫学效应的规律。并在原代培养的海马神经元AB毒性模型中验证了免疫后血清的生物学活性。     

Induction of cytotoxic T cell responses and tumor immunity against unrelated tumors using telomerase reverse transcriptase RNA transfected dendritic cells

The polypeptide component of telomerase (TERT) is an attractive candidate for a broadly expressed tumor rejection antigen because telomerase is silent in normal tissues but is reactivated in more than 85% of cancers. Here we show that immunization against TERT induces immunity against tumors of unrelated origin. Immunization of mice with TERT RNA-transfected dendritic cells (DC) stimulated cytotoxic T lymphocytes (CTL), which lysed melanoma and thymoma tumor cells and inhibited the growth of three unrelated tumors in mice of distinct genetic backgrounds. TERT RNA-transfected human DC stimulated TERT-specific CTL in vitro that lysed human tumor cells, including Epstein Barr virus (EBV)-transformed B cells as well as autologous tumor targets from patients with renal and prostate cancer. Tumor RNA-transfected DC were used as surrogate targets in the CTL assays, obviating the difficulties in obtaining tumor cells from cancer patients. In one instance, where a tumor cell line was successfully established in culture from a patient with renal cancer, the patient's tumor cells were efficiently lysed by the CTL. Immunization with tumor RNA was generally more effective than immunization with TERT RNA, suggesting that an optimal immunization protocol may have to include TERT as well as additional tumor antigens.     

In vitro cytotoxicity against Marek's disease lymphoblastoid cell lines after enzymatic removal of Marek's disease tumor-associated surface antigen.

Marek's disease tumor-associated surface antigen (MATSA) has been claimed to be the target of cytotoxic lymphocytes in in vitro tests for Marek's disease immunity. Treatment with papain, but not with trypsin or mixed glycosidases, removed MATSA from certain Marek's disease lymphoblastoid cell lines. Tumor cells with and without MATSA were used as target cells for in vitro studies on cell-mediated immune responses with sensitized spleen cells in a chromium release assay. The removal of MATSA did not influence the results of the chromium release assay. Attempts to block the cell-mediated cytotoxicity in vitro by coating tumor cells with an anti-MATSA serum failed. It was concluded that cell-mediated immune responses against Marek's disease tumor cells are directed against an as yet undefined antigen(s).     

Induction of immune response against NY-ESO-1 by CHP-NY-ESO-1 vaccination and immune regulation in a melanoma patient

BACKGROUND: NY-ESO-1 is a cancer/testis antigen highly immunogenic in cancer patients. Cholesterol-bearing hydrophobized pullulan (CHP) is a nanoparticle-forming antigen-delivery vehicle and CHP complexed with NY-ESO-1 protein (CHP-NY-ESO-1) efficiently activates CD4 and CD8 T cells in vitro. AIM: In this study we report on a 50-year-old male melanoma patient with multiple skin and organ metastases (T4N3M1c) who was vaccinated with CHP-NY-ESO-1 at biweekly intervals and who had an unusual disease course. We characterized in this patient humoral and cellular immune responses, immune regulatory cells, and cytokine profiles in the peripheral blood and at local tumor sites. RESULTS: Ten days after the second CHP-NY-ESO-1 vaccination (day 25), blisters appeared on the skin at the metastatic lesions associated with inflammatory changes. A skin biopsy showed the presence of many NY-ESO-1-expressing apoptotic melanoma cells as determined by a terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling (TUNEL) test. However, the tumors continued to grow, and the patient died of pulmonary failure due to multiple metastases on day 48. Serum antibody responses were detected after the second CHP-NY-ESO-1 vaccination and antibody titer increased with subsequent vaccinations. Th1 dependent IgG1 was the predominant immunoglobulin subtype. Both, NY-ESO-1-specific CD4 and CD8 T cell responses were detected in PBMC by IFN-gamma secretion assays. After CHP-NY-ESO-1 vaccination a slight decrease in CD4(+)CD25(+)Foxp3(+) Tregs was observed in PBMC but significantly increased numbers of CD4(+)CD25(+)Foxp3(+) Tregs and CD68(+) immunoregulatory macrophages were detected at the local tumor sites. CD4(+)CD25(+)Foxp3(+) Tregs were also increased in the blister fluid. Cytokines in the serum suggested a polarization towards a Th1 pattern in the PBMC and those in the blister fluid suggested a Th2-type response at the tumor site. CONCLUSIONS: Our observations indicate induction of specific humoral and cellular immune responses against NY-ESO-1 after CHP-NY-ESO-1 vaccination in a melanoma patient. The concomitant appearance of regulatory T cells and of immune regulatory macrophages and cytokines at the local tumor sites in this patient may explain immune escape.     

Induction of immune response to influenza virus with anti-idiotypic antibodies.

Anti-idiotypic (anti-Id) antibodies were raised in rabbits against five monoclonal antibodies (MAbs) specific for different antigenic sites on the hemagglutinin (HA) of influenza virus Mem71H-BelN (H3N1) [A/Memphis/1/71 (H3N2) x A/Bel/42 (H1N1)]. Each of the anti-Id sera was directed predominantly towards a unique (private) idiotype of the immunizing MAb, none of the five idiotypes being detectable in pooled BALB/c antisera against Mem71H-BelN virus or on most other anti-HA MAbs tested. Partial idiotypic sharing was observed, however, between certain MAbs, from different mice, having the same or similar epitope specificity for HA. When used as immunogens in BALB/c mice, two of the five anti-Id preparations induced antibodies that reacted with Mem71H-BelN virus and displayed neutralizing activity. Mice of other inbred strains responded similarly, indicating that the response was not genetically restricted by the Igh locus. From their pattern of reactivity with mutants of Mem71H-BelN virus with known single amino acid substitutions in the HA molecule, the antiviral antibodies elicited by anti-Id antibodies were shown to be directed to the same antigenic site on A/Memphis/1/71 HA as the original immunizing MAb (site A or site E, respectively). However, several of these antisera were shown to contain additional distinct subpopulations of antibodies specific for heterologous influenza A virus strains, either of the H3 subtype or of a different HA subtype (H1 or H2). Since the induction of antibodies to HA of different subtypes is not a feature of the antibody response to influenza virus itself, their induction by anti-Id antibodies merits further investigation.     

Macrophage restriction of Marek's disease virus replication and lymphoma cell proliferation.

Macrophages are shown to restrict the replication of Marek's disease virus (MDV) and isotope uptake by spleen cells from chickens bearing Marek's disease (MD) tumors. The titer of virus from duck embryo fibroblasts (DEF) co-cultivation with MDV-spleen cells pretreated to deplete marcophages was 4- to 18-fold higher than with untreated cells. Treated MDV-spleen cells increased isotope uptake by 2-fold. These restrictive activities are attributable to macrophage regulation of cell proliferation.     

Induction of heterosubtypic immunity to influenza virus by intranasal immunization

Recovery from live influenza virus infection is known to induce heterosubtypic immunity. In contrast, immunity induced by inactivated vaccines is predominantly subtype specific. In this study, we investigated the heterosubtypic protective immunity induced by inactivated influenza virus. Intranasal immunization of mice with inactivated influenza virus A/PR8 (H1N1) provided complete protection against the homologous virus and a drift virus within the same subtype, A/WSN (H1N1), but not against the heterosubtypic virus A/Philippines (H3N2). However, coadministration of inactivated virus with cholera toxin as an adjuvant conferred complete heterosubtypic protection, without observed illness, even under conditions of CD4⁺ or CD8⁺ T-cell depletion. Analysis of immune correlates prior to challenge and postchallenge indicated that humoral immune responses with cross-neutralizing activity in lungs and in sera play a major role in conferring protective immunity against heterosubtypic challenge. This study has significant implications for developing broadly cross-reactive vaccines against newly emerging pathogenic influenza viruses.     

Bacterial kidney disease as a model for studies of cell mediated immunity in rainbow trout (Oncorhynchus mykiss)

A cell mediated immune (CMI) response was measured in vitro to heat-killed and to paraformaldehyde fixed Renibacterium salmoninarum (Rs) in rainbow trout (Oncorhynchus mykiss) experimentally challenged with live Rs. The mitogenic response to the T lymphocyte mitogen Concanavalin A (Con A) was reduced during samplings 4 to 6 weeks after immersion, but no effect of the response to the B lymphocyte mitogen lipopolysaccharide (LPS) was detected. The subpopulation of lymphocytes, detected by the monoclonal antibody 1C2, was decreased from the 4th week to the 5th week of infection, and remained at the decreased level up to 10 weeks post immersion. The proportion of Immunoglobulin (Ig) bearing lymphocytes was not affected during the Rs infection period. The humoral antibody level to heat-stable Rs-antigens was increased up to 10 weeks after immersion but after 27 weeks was reduced to a level similar to that of the non-challenged fish. An anamnestic response was demonstrated in challenged fish, as intraperitoneal injection of heat-treated Rs bacteria into Rs challenged fish elicited a stronger humoral antibody response compared with injection into non-challenged fish.     

Cytotoxic cells suppress in vitro generation of cellular immunity by stimulator cell lysis

Irradiated BALB/c spleen-cell populations actively cytotoxic to BL/6 alloantigens (modulator cells) were capable of suppression of the in vitro generation of BALB/c anti-BL/6 cellular cytotoxicity. This suppression was abrogated by anti-θ serum plus complement. The suppression was dose dependent on the number of modulator cells and correlated directly with the magnitude of their cytotoxicity. By varying the number of stimulator cells, specific suppression for a relevant stimulator cell and nonspecific suppression for an irrelevant stimulator cell were demonstrated in the same cultures. These data suggest that cytotoxic cells caused specific suppression in mixed lymphocyte culture by lysing stimulator cells although evidence for other nonspecific suppressor factors was seen. A model was proposed suggesting that cell populations possessing high levels of cytotoxicity may feed back negatively on an ongoing immune response by competing with proliferating T cells for cellular antigen.     

The RNA subunit of telomerase is encoded by Marek's disease virus

Marek's disease virus (MDV) is a herpesvirus of chickens that induces T lymphomas and tumors within 4 to 5 weeks of infection. Although the ability of MDV to induce tumors was demonstrated many years ago and although a number of viral oncogenic proteins have been identified, the mechanism by which the MDV is implicated in tumorigenesis is still unknown. We report the identification of a virus-encoded RNA telomerase subunit (vTR) within the genome of MDV. This gene is found in the genomic DNA of the oncogenic MDV strains, whereas it is not carried by the nononcogenic MDV strains. The vTR sequence exhibits 88% sequence identity with the chicken gene (cTR). Our functional analysis suggests that this telomerase RNA can reconstitute telomerase activity in a heterologous system (the knockout murine TR(-/-) cell line) by interacting with the telomerase protein component encoded by the host cell. We have also demonstrated that the vTR promoter region is efficient whatever the species of cell line considered and that vTR is expressed in vivo in peripheral blood leukocytes from chickens infected with the oncogenic MDV-RB1B and the vaccine MDV-Rispens strains. The functionality of the vTR gene and the potential implication of vTR in the oncogenesis induced by MDV is discussed.     

Induction of the immune response to cell surface antigens in vitro

Summary Two tissue culture incubation systems are described in which immune responses to cell surface antigens have been demonstrated In the one-way “mixed lymphocyte interaction” system, a specific stimulation of thymidine uptake was induced by a particulate membrane antigen fraction, the microsomal lipoproteins (MLP)when low levels (0.01 to 0.001 μg per ml) were incubated with spleen or lymph node cells from nonsensitized mice. No stimulation was seen when allogeneic MLP was used at high levels, 10 μg per ml, nor at any level with syngeneic MLP. Specific effectors were demonstrated after 72-hr incubation with stimulatory levels of allogeneic MLP in three separate in vitro assays, a plaque-forming cell reduction assay, a tumor target assay, and an antigen-binding cell assay. In the latter assay, [¹²⁵I]MLP was used as the source of antigen. This system has limited potential inasmuch as mouse spleen cells do not survive in it beyond the 4th day of culture. The second tissue culture system, the Marbrook system, has much greater possibilities because at least 25% of the inoculum is recovered 7days later. In this culture system a cell-free sheep erythrocyte membrane preparation can induce, plaque-forming cells in the absence of macrophages. Using a sensitive radioimmunoassay, frees specific antibody was detected in culture supernatant fluids. With the same culture system, allogeneic lymphocytotoxic cells (killer) have been induced with spleen cells from unprimed mice in strains differing at the major histocompatibility locus (H-2). Allogeneic MLP induced very significant “killer” cell activity with spleen cells from primed mice. In a syngeneic tumor systems, significant amounts of killer cell activity were induced with unprimed spleen cell inocula, and much larger amounts induced with spleen cells from immunized mice. Presented in the formal symposium on Carcinogenesis in Vitro, at the 25th Annual Meeting of the Tissue Culture Association, Miami Beach, Florida, June 3–6, 1974. This work was supported by Public Health Service Rescarch grants CA 07973 and CA 10815 from the National Cancer Institute.     

Antibody response against strains of influenza-A virus in ferrets with basic immunity

Summary In Holland ferrets are offered for sale with basic antibodies against one or more sub-groups of strains of influenza-A virus. With the haemagglutination inhibition test low basic antibody titers can only be detected by neutralising the non-specific inhibitor in the ferret sera. When such a ferret is infected with a strain of a heterologous sub-group, a considerable rise in antibodies is obtained against the homologous and heterologous sub-groups. It is very probable that the same holds for human beings. Some examples are given of haemagglutination-inhibition tests with serum pairs from adults who suffered from influenza in the epidemic of the winter of 1949 in Holland from which the non-specific inhibitor had been eliminated.Sub-unit of the Influenza Research Team of the Institute of Preventive Medicine, Leyden. With the financial support of the Institute of Preventive Medicine, the Department of Medical Research Philips Roxane (Weesp), the State Department of Science, and the Jan Dekker Fund.