[Relevance of polymerase chain reaction technique in immunogenetics and histocompatibility]

INTRODUCTION

During the last decade of the previous century, among many of developing sciences, molecular biology had the most important position. The greatest influence on the development of scientific knowledge had been brought by discovery of PCR technique, that showed numerous advantages in comparison to the existing techniques.

PCR PROCEDURE

The capability of PCR technique to amplify specific DNA sequences, in a simple, automatic procedure, accelerated the development of many fields in molecular biology researches such as cloning, identification of new genes and pathogenes, determination and quantification of nucleotide sequences, thus opening fields of experimental investigations and its clinical application. PCR technique is widely used in various investigations from anthropological researches to those in molecular biology, from basic genetic investigations to clinical diagnostics.

APPLICATION OF PCR PROCEDURE IN THE FIELD OF IMMUNOGENETICS AND HISTOCOMPATIBILITY

In the field of immunogenetics and histocompatibility, there are several HLA genotyping techniques: PCR-SSOP, detection by sequence specific oligonucleotide probes. PCR-SSP, detection by sequence specific primers, RSCA, detection by Reference-Strand Conformation Analysis, SBT-Sequence Based Typing. The development of these techniques has enabled the testing of the HLA alleles as well as detection of shared nucleotide sequences between alleles on the same or/and different loci and the existence of some locus-specific nucleotide sequences in coding (exon) and noncoding (intron) regions.

CONCLUSION

The application of PCR technique in immunogenetics made it possible to define genetic polymorphism in HLA system, which contributed to a significant progress in the field of tissue and organ transplantation, population and genetic studies as well as in studies of disease association and HLA alleles.

Multiparameter analysis of immunogenetic mechanisms in clinical diagnosis and management of inflammatory bowel disease

The integrity of the intestinal mucosa depends on a functional coordination of the epithelium, lumenal microorganisms, and the local immune system. The mammalian immune system is superbly organized for innate and adaptive recognition of microbial antigens, a defensive capacity that must be balanced against the tissue damage produced by immune activity to preserve normal intestinal function. Inflammatory bowel disease (IBD) is generally thought to reflect an impairment in this balance, due to a combination of host genetic traits that shift the balance of immune and epithelial function to commensal microbiota, and perhaps the composition or activity of certain microbial elements as well. There has been much progress defining the fundamental disorders of these host traits, immunologic processes, and microbial targets in inflammatory bowel disease. Other fields of clinical and geologic microbiology are teaching us about the dynamic interaction of commensal bacteria with their host environment. These lines of investigation have revealed not only important insights about inflammatory bowel disease (IBD) pathogenesis, but also defined technologies and tools useful for its diagnosis and clinical management. This review focuses on these advances at the translational interface. We will first consider the innate anti-microbial response, centering on the utility of NOD2 genotyping for predicting disease susceptibility, prognosis, and therapeutic response profile. We will then turn to the adaptive anti-microbial response, focusing on the application of antibodies to fungal and bacterial species and products for Crohn's disease (CD) diagnosis and prognosis, and immunogenetics of T cell immunosuppression management. Finally, we will describe autoimmune mechanisms in IBD, with particular attention to autoantibodies in IBD diagnosis and infliximab responsiveness. We will conclude with the concept of multiparameter analysis of patients, to refine patient characterization and stratification in diagnosis and clinical management.

[Immunogenetic criteria for prediction of mixed hepatitis A + B]

The investigation has revealed that mixed hepatitis A + B is a genetically determined disease. HLA-A10, B21, Cw2, Cw5, A10-A19, B8-B13, B21-B35, A3-B21, and A9-B21 are immunogenetic markers of this disease. The carriers of HLA-B21, Cw5, A3-B21, and A9-B21 and those of HLA-A10, A10-A19, and A10-B14 are at high risk for this infection among men and women, respectively. The findings of the distribution of HLA antigens and their combinations in mixed infection with hepatitis A and B viruses allow prediction of its occurrence (including the consideration of examinees' gender) which will assist in solving the matter of timely prophylaxis of this pathology.

Immunogene therapy by adenovirus vector expressing CD40 ligand for metastatic liver cancer in rats

BACKGROUND

We have explored a gene-therapeutic approach to stimulate antitumor immunity by adenoviral-mediated transfer of CD40 ligand (CD40L) to treat metastatic liver cancer in a rat model.

MATERIALS AND METHODS

Rat metastatic liver cancer cells were implanted into the back of rats bilaterally. When the larger tumor reached 8.0 mm in diameter, adenovirus vector-expressing mouse CD40L was injected intratumorally as treatment group (n=5), while LacZ was injected in the control group (n=5).

RESULTS

In the control group, the tumor gradually grew to be 20.7+/-1.6 (mean+/-SD) mm in intratumorally injected tumors and 21.8+/-3.7 mm in opposite tumors seven weeks after injection, respectively. In contrast, in the treatment group, the tumor was reduced to 3.6+/-8.2 mm and 3.7+/-8.2 mm. The tumor growth and survival rate were significantly different (p<0.001).

CONCLUSION

Adenovirus vector-mediated CD40L gene therapy is an effective therapeutic method for metastatic liver cancer.

The clinical and immunogenetic characteristics of adult-onset type 1 diabetes mellitus in Korea

Although the HLA class II alleles and immunological abnormalities are associated with type 1 diabetes mellitus (T1DM) in all racial groups, there are considerable variations in the genotypes and the prevalence of autoantibodies. In order to investigate the characteristics of the immunogenetic patterns and to use these as an early diagnostic tool and guideline for a therapeutic plan, we examined the clinical characteristics and the patterns of anti-GAD antibody (GADA), IA-2 antibody (IA-2A), HLA-DR and HLA-DQ in Korean adult-onset T1DM patients. Adult-onset patients had higher serum C-peptide levels than child-onset patients. In adult-onset patients, the prevalence of GADA and IA-2A were 59.5% and 15.3% respectively, and increased frequencies of HLADR4 and-DR9 were found. The frequencies of HLADQA1,-DQB1 and-DQ heterodimers were similar to those of the control, but child-onset patients had high frequencies of the HLA-DR3,-DR4,-DR9, DQA1*0301, DQA1*0501 and DQB1*0201 genotypes. In conclusion, Korean adult-onset T1DM patients had a lower prevalence of GADA, which was comparable to that found in Caucasian patients. The detection of GADA might help to predict the insulin dependency of adult-onset diabetes. Difference in the frequencies of diabetes associated with HLA type suggests that there might be a heterogeneity in the pathogenesis of diabetes according to the age of onset.

Immunogenic tagging of chloroplasts allows their isolation from defined cell types

Chloroplast structure varies depending on cell type. Currently it is difficult to obtain insight into how differences in chloroplast structure relate to function, as it is often not possible to isolate chloroplasts from specific cells. To address this, we have developed an approach that involves labelling chloroplasts from individual cell types by placing the foreign yellow fluorescent protein (YFP) on their outer surface, and then isolating those labelled chloroplasts immunogenically. Cell specificity is achieved through the use of enhancer trap lines. When whole leaves are homogenized, a mixture of labelled and unlabelled chloroplasts is released, but magnetic beads coated with antibodies to the green fluorescent protein (GFP) allow the labelled chloroplasts to be isolated. Chloroplasts from spongy mesophyll, vascular and epidermal cells of Arabidopsis thaliana were obtained in this way, and semi-quantitative RT-PCR showed that the abundance of various chloroplast transcripts differed between these three cell types. The approach is based on genetic logic, and so could be applied to the isolation of various organelles or subcellular compartments from transformable organisms other than A. thaliana.

Immunogenicity of four complementary deoxyribonucleic acid fragments from rabbit zona pellucida 3 and their effects on fertility

OBJECTIVE

To evaluate the exact region in different exons of rabbit zona pellucida (ZP)3 involved in recognition and binding between sperm and the ZP.

DESIGN

Prospective study of a female immunocontraceptive.

SETTING

State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences.

ANIMAL(S)

BALB/C mice.

INTERVENTION(S)

Immunization recombinant vaccines.

MAIN OUTCOME MEASURE(S)

Oocyte immunofluorescence and immunohistochemistry.

RESULT(S)

The immunogenicity and effects on fertility of these four fragments we used were different. Except for the ZP domain, the other three fragments of rabbit ZP3 may be useful as antigen to elicit antibodies. Antiserum was specific and obvious. The fertility of mice after immunization decreased slightly compared with the control.

CONCLUSION(S)

The most effective fragment that is associated with the sperm binding was from sequences contained in exons 5-8 or oligosaccharide linked to this region. Exons 5-8 or oligosaccharide linked to this region may exist outside of the ZP matrix and be safe for use as the antigen. The ZP domain may be not related to the recognition and binding.

Artificial carriers: a strategy for constructing antigenic/immunogenic conjugates

The rational design of artificial carriers for anchoring multiple copies of B and/or T cell epitopes, built-in vaccine adjuvants and "promiscuous" T cell epitopes for the construction of conjugates as antigenic substrates or potent immunogens has been the stimulus of intensive efforts nowadays. The unambiguous composition, the reliability and the versatility of the production of reconstituted antigens or immunogens has found a great number of biochemical applications in developing immunoassays of high sensitivity, specificity and reproducibility and in generating site-specific antibodies for usage as human vaccine candidates. In this review are summarized different types of artificial carriers currently used as dendrimers bearing branching segments, multimeric core matrices and templates with built-in folding devices. Emphasis is given to the construction and application of a helicoid-type Sequential Oligopeptide Carrier (SOCn) developed in our laboratory. The beneficial structural elements of SOCn induce a favorable arrangement of the conjugated peptides, which also retain their initial "active" conformation, so that potent antigens and immunogens are generated.

Immunoproteome analysis of soluble and membrane proteins of Shigella flexneri 2457T

AIM

To profile the immunogenic proteins of Shigella flexneri (S. flexneri) expressed during human infection using a proteomic approach.

METHODS

Soluble and membrane protein extractions of S. flexneri 2457T were separated by two-dimensional gel electrophoresis (2-DE). Proteins were transferred to PVDF membrane and immunoblotted with sera from shigellosis patients. Reactive protein spots were matched to Coomassie stained gels run in parallel, cut out and trypsin digested. Matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS) was used to determine the peptide mass fingerprints, which were searched in the MASCOT database to identify the protein.

RESULTS

A total of 8 immunoreactive proteins were successfully identified from the Coomassie stained gels in three repeats. Six of these proteins have not previously been reported as immunogenic in S. flexneri. These proteins could be potential candidates for vaccine or attenuation studies.

CONCLUSION

Soluble and membrane proteins of S. flexneri 2457T have been screened by 2-DE and immunoblotting with sera from shigellosis patients. Eight proteins are identified as immunogenic.

[Population genetic study of Russian cosmonauts and test subjects: genetic demographic parameters and immunogenetic markers]

Genetic demographic characteristics and immunogenetic markers (blood groups ABO, Rhesus, MNSs, P, Duffy, Kidd, and Kell) have been studied in a group of 132 Russian cosmonauts and test subjects (CTSG). Analysis of pedigrees has shown a high exogamy in the preceding generations: almost half of the subjects have mixed ethnic background. According to the results of genetic demographic analysis, a sample from the Moscow population was used as control group (CG). Comparison between the CTSG and CG has demonstrated significant differences in genotype frequencies for several blood group systems. The CTSG is characterized by a decreased proportion of rare interlocus genotypic combinations and an increased man heterozygosity. Analysis of the distributions of individual heterozygosity for loci with codominant expression of alleles has shown that highly heterozygous loci are more frequent in the CTSG. Taking into account that the CTSG has been thoroughly selected from the general population, it is concluded that heterozygosity is related to successful adaptation to a space flight.

Immunogenomics: molecular hide and seek

Similar to other classical science disciplines, immunology has been embracing novel technologies and approaches giving rise to specialised sub-disciplines such as immunogenetics and, more recently, immunogenomics, which, in many ways, is the genome-wide application of immunogenetic approaches. Here, recent progress in the understanding of the immune sub-genome will be reviewed, and the ways in which immunogenomic datasets consisting of genetic and epigenetic variation, linkage disequilibrium and recombination can be harnessed for disease association and evolutionary studies will be discussed. The discussion will focus on data available for the major histocompatibility complex and the leukocyte receptor complex, the two most polymorphic regions of the human immune sub-genome.

Technical hurdles in a pilot clinical trial of combined B7-2 and GM-CSF immunogene therapy for glioblastomas and melanomas

OBJECTIVE

Malignant glioblastomas and melanomas continue to have a dismal prognosis despite advances in conventional therapy. This has led to investigations of novel treatment strategies including immunogene therapy. We report a pilot clinical trial of combined B7-2 and GM-CSF immunogene therapy for gliomas and melanomas and discuss technical hurdles encountered.

METHODS

Patients with recurrent malignant gliomas or medically refractory melanomas were vaccinated with irradiated autologous tumor cells transduced with B7-2 and GM-CSF genes using a retroviral vector. Patients were monitored for toxicity, inflammatory/immune reactions, and clinical status.

RESULTS

Vaccine preparation was attempted from 116 malignant glioma and 32 melanoma specimens. Adequate vaccines could only be prepared for five glioblastoma and three melanoma patients. Six patients (three recurrent glioblastomas and three melanomas) were actually vaccinated. Minor toxicities included flu-like symptoms (3/6), injection site erythema (4/6), and asymptomatic elevations in liver enzymes (3/6). Most patients showed evidence of an inflammatory response but specific anti-tumor immunity was not demonstrated. All six patients have died, although three patients with minimal residual disease at treatment had prolonged recurrence-free intervals after vaccination.

CONCLUSIONS

Combined B7-2 and GM-CSF immunogene therapy for glioblastomas and melanomas using autologous tumor cells has many technical pitfalls hindering large scale application and evaluation. As a result, this pilot study was too limited to draw meaningful conclusions regarding safety or anti-tumor immunity. While immunotherapy has been promising in pre-clinical studies, alternate strategies will be required to bring these benefits to patients.

From immunogenic mechanisms to novel therapeutic approaches in inflammatory bowel disease

Crohn's disease (CD) and ulcerative colitis (UC) are the two most common forms of chronic inflammatory bowel disease (IBD). The etiology of IBD is still unclear and should be considered as multi-factorial according to recent studies. Genetic factors seem to play a pathogenetic role as well as environmental, infectious and immulogical factors. Substantial progress, however, has been made in the understanding of the pathogenesis of IBD during the past years persuing the view, that IBD could result from disturbances of the intestinal barrier and a pathologic activation of the intestinal immune response towards luminal, bacterial antigens. This paradigm has led to the identification of key players of the intestinal immune system, which represent promising targets for novel therapeutic approaches. The objective of this chapter is to provide an overview over recent advances in the elucidation of the intestinal immune system in IBD and novel therapeutic approaches that have been derived from these results. Molecular biological techniques have revealed, that many of the established conventional antiinflammatory drugs such as salicylic acids, steroids or immunuosuppressants act at the same molecules that are the target for modern biologicals, i.e., the cytokine TNF or the transcription factor NFkappaB. This chapter, however, focusses on novel experimental approaches such as recombinant antiinflammatory cytokines, neutralizing antibodies or antisense oligonucleotides.

[Immunogenetics--HLA-association, molecular chaperones and "related" diseases]

The association of rheumatoid arthritis (RA) with the HLA complex has been well established since 1978. But what does that mean? After reminding the reader of some existing immunological interpretations, a more recent variant is introduced. Antigens and molecular chaperones of the HSP70 family form complexes, which interact with HLA-DR beta-chains, especially of the DRB1*0401 genotype, which is the most common among patients with RA in our region. This mechanism might bring *0401(+) persons an advantage in defence against microorganisms, but a disadvantage concerning autoimmunity. Chaperone machines are upregulated in synovial tissue of RA patients. As their number and variety is huge in humans, there exist many possibilities for function, reaching from antigen presentation to immune regulation. In addition to the HLA complex, the "genetic background" plays an important role for the development of an autoimmune disease. This is demonstrated in families of patients with RA or scleroderma, where a high percentage of first degree relatives suffer from a "related" disease.

DNA array-based gene profiling in tumor immunology

Recent advances in tumor immunology have fostered the clinical implementation of different immunotherapy modalities. However, the alternate success of such regimens underscores the fact that the molecular mechanisms underlying tumor immune rejection are still poorly understood. Given the complexity of the immune system network and the multidimensionality of tumor-host interactions, the comprehension of tumor immunology might greatly benefit from high-throughput DNA array analysis, which can portray the molecular kinetics of immune response on a genome-wide scale, thus accelerating the accumulation of knowledge and ultimately catalyzing the development of new hypotheses in cell biology. Although in its infancy, the implementation of DNA array technology in tumor immunology studies has already provided investigators with novel data and intriguing hypotheses on the cascade of molecular events leading to an effective immune response against cancer. Although the principles of DNA array-based gene profiling techniques have become common knowledge, the need for mastering this technique to produce meaningful data and correctly interpret this enormous output of information is critical and represents a tremendous challenge for investigators. In the present work, we summarize the main technical features and critical issues characterizing this powerful laboratory tool and review its applications in the fascinating field of cancer immunogenomics.

IMGT-Choreography for immunogenetics and immunoinformatics

IMGT, the international ImMunoGeneTics information system (http://imgt.cines.fr), was created in 1989 at Montpellier, France. IMGT is a high quality integrated knowledge resource specialized in immunoglobulins (IG), T cell receptors (TR), major histocompatibility complex (MHC) of human and other vertebrates, and related proteins of the immune system (RPI) which belong to the immunoglobulin superfamily (IgSF) and MHC superfamily (MhcSF). IMGT provides a common access to standardized data from genome, proteome, genetics and three-dimensional structures. The accuracy and the consistency of IMGT data are based on IMGT-ONTOLOGY, a semantic specification of terms to be used in immunogenetics and immunoinformatics. IMGT-ONTOLOGY has been formalized using XML Schema (IMGT-ML) for interoperability with other information systems. We are developing Web services to automatically query IMGT databases and tools. This is the first step towards IMGT-Choreography which will trigger and coordinate dynamic interactions between IMGT Web services to process complex significant biological and clinical requests. IMGT-Choreography will further increase the IMGT leadership in immunogenetics and immunoinformatics for medical research (repertoire analysis of the IG antibody sites and of the TR recognition sites in autoimmune and infectious diseases, AIDS, leukemias, lymphomas, myelomas), veterinary research (IG and TR repertoires in farm and wild life species), genome diversity and genome evolution studies of the adaptive immune responses, biotechnology related to antibody engineering (single chain Fragment variable (scFv), phage displays, combinatorial libraries, chimeric, humanized and human antibodies), diagnostics (detection and follow up of residual diseases) and therapeutical approaches (grafts, immunotherapy, vaccinology). IMGT is freely available at http://imgt.cines.fr.

Non-major histocompatibility complex alloantigen genes affecting immunity

An alloantigen is a genetically determined cell-surface molecule detected by specific antisera. An identifying letter has been assigned to each genetic locus responsible for the 12 distinct families of alloantigens: A, B, C, D, E, H, I, J, K, L, P, and R. The genes of each system segregate independently of the other systems, except that the A and E are very closely linked (0.5 centimorgans). Selection experiments over numerous generations have revealed distinct changes in gene frequency of the A-E alloantigens, suggesting immune responses associated with susceptibility to coccidiosis, response to immunizations with SRBC, and selection for size of the bursa of Fabricius. Immune response effects of the C system of alloantigen genes are indicated by distinct gene frequency changes following selection for response to SRBC, selection for size of bursa of Fabricius, and macrophage nitrite production after lipopolysaccharide (LPS) stimulation. Immune response effects of the D system of antigens are indicated by data from genetic selection for response to immunization with SRBC, selection for bursa size, and macrophage nitrite and cytokine interleukin (IL)-6 production following LPS stimulation. Immune response effects of the I system genes are indicated by distinct gene frequency changes in lines selected for bursa size and within family comparisons for macrophage nitrite and cytokine IL-6 production following LPS stimulation. Effects of the L system, consisting of only 2 alleles, are indicated by the gene frequency changes following selection for bursa size, direct comparison of genotypes within families for monocyte phagocytosis, susceptibility to coccidiosis, outcome of Rous sarcomas, and immune responses to SRBC and Brucella abortus. Genotypes of the P alloantigen system were directly compared within families of fully pedigreed chicks with significant differences for monocyte phagocytosis. An experimental procedure for simultaneously testing for immune responses of genotypes of 9 of the alloantigen systems (A, B, C, D, E, H, I, L, and P) has been established by producing test progeny from a single cross of parent lines segregating for genes of each of the systems.

Construction and characterization of novel staphylokinase variants with antiplatelet aggregation activity and reduced immunogenecity

To develop target thrombolytic agents with fibrinolytic activity, antiplatelet aggregation activity and reduced immunogenicity, two staphylokinase variants containing Arg-Gly-Asp (RGD) motif were constructed. Gene expression was induced in E. coli JF1125 and the variants, designated DGR and RL1, were purified with gel filtration and ion-exchange chromatography and the purity was over 95%. The fibrinolytic activity and kinetic constants of the two variants were comparable to those of recombinant wild-type staphylokinase. Both the variants can inhibit the platelet aggregation at a final concentration of 2 microM. The titers of antibodies against variants were much lower than those against recombinant staphylokinase in guinea pigs, which indicated that the immunogenicity of the variants was greatly reduced. These results confirm that it is possible to design and produce a bifunctional protein that possesses fibrinolytic and antiplatelet aggregation activities.

Prediction of exposed domains of envelope glycoprotein in Indian HIV-1 isolates and experimental confirmation of their immunogenicity in humans

We describe the impact of subtype differences on the seroreactivity of linear antigenic epitopes in envelope glycoprotein of HIV-1 isolates from different geographical locations. By computer analysis, we predicted potential antigenic sites of envelope glycoprotein (gp120 and gp4l) of this virus. For this purpose, after fetching sequences of proteins of interest from data banks, values of hydrophilicity, flexibility, accessibility, inverted hydrophobicity, and secondary structure were considered. We identified several potential antigenic epitopes in a B subtype strain of envelope glycoprotein of HIV-1 (IIIB). Solid- phase peptide synthesis methods of Merrifield and Fmoc chemistry were used for synthesizing peptides. These synthetic peptides corresponded mainly to the C2, V3 and CD4 binding sites of gp120 and some parts of the ectodomain of gp41. The reactivity of these peptides was tested by ELISA against different HIV-1-positive sera from different locations in India. For two of these predicted epitopes, the corresponding Indian consensus sequences (LAIERYLKQQLLGWG and DIIGDIRQAHCNISEDKWNET) (subtype C) were also synthesized and their reactivity was tested by ELISA. These peptides also distinguished HIV-1-positive sera of Indians with C subtype infections from sera from HIV-negative subjects.

Exploring and exploiting bacterial proteomes

The plethora of data now available from bacterial genome sequencing has opened a wealth of new research opportunities. Many of these have been reviewed in preceding chapters. Genomics alone, however, cannot capture a biological snapshot from an organism at a given point in time. The genome itself is static, and it is the changes in expression of genes, leading to the production of functional proteins, which allows an organism to survive and adapt to a constantly changing environment. Proteomics is the term used to describe the global analysis of proteins involved in a particular biological process. Such processes may be analyzed via comparative studies that examine bacterial strain differences, both phenotypic and genetic, bacteria grown under nutrient limiting conditions, growth phase, temperature, or in the presence of chemical compounds, such as antibiotics. Proteomics also provides the researcher with a tool to begin characterizing the functions of the vast proportion of "hypothetical" or "unknown" proteins elucidated from genome sequencing and database comparisons. For example, study of protein-protein, protein-ligand, protein-substrate, and protein-nucleic acid interactions for a given target protein may all help to define the functions of previously unknown proteins. Furthermore, genetic manipulation combined with proteomics technologies can provide an understanding of how gene expression is regulated. This chapter examines the technologies used in proteome analysis and the applications of proteomics to microbiological research, with an emphasis on clinically-relevant bacteria.

Induction of an antitumor immunological response by an intratumoral injection of dendritic cells pulsed with genetically engineered Semliki Forest virus to produce interleukin-18 combined with the systemic administration of interleukin-12

OBJECT

The aim of this study was to investigate further immunogene treatment of malignant brain tumor to improve its therapeutic efficacy.

METHODS

Intratumoral dendritic cells pulsed with Semliki Forest virus (SFV)-interleukin-18 (IL-18) and/or systemic IL-12 were injected into mice bearing the B16 brain tumor. To study the immune mechanisms involved in tumor regression, we monitored the growth of implanted B16 brain tumor cells in T cell-depleted mice and IFNgamma-neutralized mice. To analyze the protective immunity created by tumor inoculation, B16 cells were injected into the left thighs of mice that had received an inoculation, and tumor growth was monitored. The local delivery of dendritic cells pulsed with IL-18 bound by SFV combined with the systemic administration of IL-12 enhanced the induction of the T helper type 1 response from tumor-specific CD4+ and CD8+ T cells and natural killer cells as well as antitumor immunity. Interferon-gamma is partly responsible for this IL-18-mediated antitumor immunity. Furthermore, the protective immunity is mediated mainly by CD8+ T cells.

CONCLUSIONS

Immunogene therapy that combines the local administration of dendritic cells pulsed with IL-18 bound by SFV and the systemic administration of IL-12 may be an excellent candidate for the development of a new treatment protocol. A self-replicating SFV system may therefore open a novel approach for the treatment of malignant brain tumor.