Liposome-Mediated Delivery of MERS Antigen Induces Potent Humoral and Cell-Mediated Immune Response in Mice.

The advancements in the field of nanotechnology have provided a great platform for the development of effective antiviral vaccines. Liposome-mediated delivery of antigens has been shown to induce the antigen-specific stimulation of the humoral and cell-mediated immune responses. Here, we prepared dried, reconstituted vesicles (DRVs) from DPPC liposomes and used them as the vaccine carrier system for the Middle East respiratory syndrome coronavirus papain-like protease (DRVs-MERS-CoV PLpro). MERS-CoV PLpro emulsified in the Incomplete Freund's Adjuvant (IFA-MERS-CoV PLpro) was used as a control. Immunization of mice with DRVs-MERS-CoV PLpro did not induce any notable toxicity, as revealed by the levels of the serum alanine transaminase (ALT), aspartate transaminase (AST), blood urea nitrogen (BUN) and lactate dehydrogenase (LDH) in the blood of immunized mice. Immunization with DRVs-MERS-CoV PLpro induced greater antigen-specific antibody titer and switching of IgG1 isotyping to IgG2a as compared to immunization with IFA-MERS-CoV PLpro. Moreover, splenocytes from mice immunized with DRVs-MERS-CoV PLpro exhibited greater proliferation in response to antigen stimulation. Moreover, splenocytes from DRVs-MERS-CoV PLpro-immunized mice secreted significantly higher IFN-γ as compared to splenocytes from IFA-MERS-CoV PLpro mice. In summary, DRVs-MERS-CoV PLpro may prove to be an effective prophylactic formulation to prevent MERS-CoV infection.

The level of decoy epitope in PCV2 vaccine affects the neutralizing activity of sera in the immunized animals.

Viral pathogens have evolved a wide range of tactics to evade host immune responses and thus propagate effectively. One efficient tactic is to divert host immune responses toward an immunodominant decoy epitope and to induce non-neutralizing antibodies toward this epitope. Therefore, it is expected that the amount of decoy epitope in a subunit vaccine can affect the level of neutralizing antibody in an immunized animal. In this study, we tested this hypothesis by generating an antibody specific to the decoy epitope on the capsid protein of porcine circovirus type 2 (PCV2). Using this antibody, we found that two commercial vaccines contained statistically different amounts of the decoy epitope. The vaccine with lower levels of decoy epitope induced a significantly higher level of neutralizing antibody after immunization. This antibody can be used as an analytical tool to monitor the quality of a vaccine from batch to batch.

Chitosan tripolyphosphate (CS/TPP) nanoparticles: preparation, characterization and application for gene delivery in shrimp.

The present study examines the use of CS/TPP nanoparticles for gene delivery in different tissues of shrimp through oral route. The viral gene of WSSV was used to construct DNA vaccines using pcDNA 3.1, a eukaryotic expression vector and the constructs were named as pVP28. The CS/TPP nanoparticles were synthesized by ionic gelation process and these particles were characterized. The structure and morphology of the nanoparticles were studied by field emission scanning electron microscopy (FE-SEM) and FTIR (Fourier Transform Infrared Spectra). The cytotoxicity of CS/TPP nanoparticles was evaluated by MTT assay using fish cell line. The expression of gene was confirmed by Immuno-dot blot, ELISA and RT-PCR analyses. The results indicate that DNA can be easily delivered into shrimp by feeding with CS/TPP nanoparticles.

DNA-chitosan nanoparticles improve DNA vaccine-elicited immunity against Newcastle disease virus through shuttling chicken interleukin-2 gene.

In this study, pCAGG-ChIL2 plasmid DNA containing the chicken interleukin-2 (ChIL-2) gene was used to prepare DNA-chitosan nanoparticles (CNPs). The CNPs prepared were spherical, with mean diameters between 100 and 200 nm, have a positive surface charge, and could protect DNA against DNase I degradation. The CNPs prepared were successfully used to transfect the Df-1 cell line with almost no cytotoxicity. CNPs prepared at an amino group to phosphate group ratio (N/P ratio) of 16 provided the highest transfection efficiency (1.1%) in medium with a pH of 6.5. When pCAGG-ChIL2 CNPs were administered to chickens simultaneously with a DNA vaccine against Newcastle disease virus (NDV), haemagglutination inhibition antibody titers and serum interferon-γ (IFN-γ) levels were significantly higher than in chickens immunised with the NDV DNA vaccine alone (p < 0.05). The results demonstrate that pCAGG-ChIL2 CNPs improve DNA vaccine-elicited immunity against NDV challenge.

A phase I trial of epstein-barr virus gp350 vaccine for children with chronic kidney disease awaiting transplantation.

BACKGROUND.: Vaccination against Epstein-Barr virus (EBV), inducing an antibody response to the envelope glycoprotein gp350, might protect EBV-negative children with chronic kidney disease from lymphoproliferative disease after transplantation. METHODS.: A phase I trial recruited children with chronic kidney disease to two successive cohorts given three injections of 12.5 microg (n=6) and 25 microg (n=10) recombinant gp350/alhydrogel vaccine over 6 to 8 weeks. RESULTS.: One in each cohort acquired wild EBV before the week 28 evaluation. Both doses were similarly immunogenic, inducing an IgG response in all 13 evaluable patients. Neutralizing antibodies were detected in four recipients (1/4 in the 12.5 microg and 3/9 in the 25 microg cohort). Median time from first vaccination to transplantation was 24 weeks. Immune responses declined rapidly and were unlikely to affect posttransplant events. DISCUSSION.: The vaccine was immunogenic but a prolonged vaccine schedule up to time of transplantation or improved adjuvants are required in future trials to reduce posttransplant EBV load and risk of lymphoproliferative disease.

Biodistribution and toxicological safety of adenovirus type 5 and type 35 vectored vaccines against human immunodeficiency virus-1 (HIV-1), Ebola, or Marburg are similar despite differing adenovirus serotype vector, manufacturer's construct, or gene inserts.

The Vaccine Research Center has developed vaccine candidates for different diseases/infectious agents (including HIV-1, Ebola, and Marburg viruses) built on an adenovirus vector platform, based on adenovirus type 5 or 35. To support clinical development of each vaccine candidate, pre-clinical studies were performed in rabbits to determine where in the body they biodistribute and how rapidly they clear, and to screen for potential toxicities (intrinsic and immunotoxicities). The vaccines biodistribute only to spleen, liver (Ad5 only), and/or iliac lymph node (Ad35 only) and otherwise remain in the site of injection muscle and overlying subcutis. Though approximately 10(11) viral particles were inoculated, already by Day 9, all but 10(3) to 10(5) genome copies per mu g of DNA had cleared from the injection site muscle. By three months, the adenovector was cleared with, at most, a few animals retaining a small number of copies in the injection site, spleen (Ad5), or iliac lymph node (Ad35). This pattern of limited biodistribution and extensive clearance is consistent regardless of differences in adenovector type (Ad5 or 35), manufacturer's construct and production methods, or gene-insert. Repeated dose toxicology studies identified treatment-related toxicities confined primarily to the sites of injection, in certain clinical pathology parameters, and in body temperatures (Ad5 vectors) and food consumption immediately post-inoculation. Systemic reactogenicity and reactogenicity at the sites of injection demonstrated reversibility. These data demonstrate the safety and suitability for investigational human use of Ad5 or Ad35 adenovector-based vaccine candidates at doses of up to 2 x 10(11) given intramuscularly to prevent various infectious diseases.

Adenovirus vector induced innate immune responses: impact upon efficacy and toxicity in gene therapy and vaccine applications.

Extensively characterized, modified, and employed for a variety of purposes, adenovirus (Ad) vectors are generally regarded as having great potential by many applied virologists who wish to manipulate and use viral biology to achieve beneficial clinical outcomes. Despite widespread functional prominence and utility (i.e., Ad-based clinical trials have begun to progress to critical Phase III levels, it has recently become apparent that investigations regarding the innate immune response to Ads may reveal not only reasons behind previous failures, but also reveal novel insights that will allow for safer, more efficacious uses of this important gene transfer platform. Insights gained by the exploration of Ad induced innate immune responses will likely be most important to the fields of vaccine development, since Ad-based vaccines are regarded as one of the more promising vaccine platforms in development today. Adenovirus is currently known to interact with several different extracellular, intracellular, and membrane-bound innate immune sensing systems. Past and recent studies involving manipulation of the Ad infectious cycle as well as use of different mutants have shed light on some of the initiation mechanisms underlying Ad induced immune responses. More recent studies using microarray-based analyses, genetically modified cell lines and/or mouse mutants, and advanced generation Ad vectors have revealed important new insights into the scope and mechanism of this cellular defensive response. This review is an attempt to synthesize these studies, update Ad biologists to the current knowledge surrounding these increasingly important issues, as well as highlight areas where future research should be directed. It should also serve as a sobering reality to researchers exploring the use of any gene transfer vector, as to the complexities potentially involved when contemplating use of such vectors for human applications.

A live, attenuated recombinant West Nile virus vaccine.

West Nile (WN) virus is an important cause of febrile exanthem and encephalitis. Since it invaded the U.S. in 1999, >19,000 human cases have been reported. The threat of continued epidemics has spurred efforts to develop vaccines. ChimeriVax-WN02 is a live, attenuated recombinant vaccine constructed from an infectious clone of yellow fever (YF) 17D virus in which the premembrane and envelope genes of 17D have been replaced by the corresponding genes of WN virus. Preclinical tests in monkeys defined sites of vaccine virus replication in vivo. ChimeriVax-WN02 and YF 17D had similar biodistribution but different multiplication kinetics. Prominent sites of replication were skin and lymphoid tissues, generally sparing vital organs. Viruses were cleared from blood by day 7 and from tissues around day 14. In a clinical study, healthy adults were inoculated with 5.0 log(10) plaque-forming units (PFU) (n = 30) or 3.0 log10 PFU (n = 15) of ChimeriVax-WN02, commercial YF vaccine (YF-VAX, n = 5), or placebo (n = 30). The incidence of adverse events in subjects receiving the vaccine was similar to that in the placebo group. Transient viremia was detected in 42 of 45 (93%) of ChimeriVax-WN02 subjects, and four of five (80%) of YF-VAX subjects. All subjects developed neutralizing antibodies to WN or YF, respectively, and the majority developed specific T cell responses. ChimeriVax-WN02 rapidly elicits strong immune responses after a single dose, and is a promising candidate warranting further evaluation for prevention of WN disease.

Toxicological safety evaluation of DNA plasmid vaccines against HIV-1, Ebola, Severe Acute Respiratory Syndrome, or West Nile virus is similar despite differing plasmid backbones or gene-inserts.

The Vaccine Research Center has developed a number of vaccine candidates for different diseases/infectious agents (HIV-1, Severe Acute Respiratory Syndrome virus, West Nile virus, and Ebola virus, plus a plasmid cytokine adjuvant-IL-2/Ig) based on a DNA plasmid vaccine platform. To support the clinical development of each of these vaccine candidates, preclinical studies were performed to screen for potential toxicities (intrinsic and immunotoxicities). All treatment-related toxicities identified in these repeated-dose toxicology studies have been confined primarily to the sites of injection and seem to be the result of both the delivery method (as they are seen in both control and treated animals) and the intended immune response to the vaccine (as they occur with greater frequency and severity in treated animals). Reactogenicity at the site of injection is generally seen to be reversible as the frequency and severity diminished between doses and between the immediate and recovery termination time points. This observation also correlated with the biodistribution data reported in the companion article (Sheets et al., 2006), in which DNA plasmid vaccine was shown to remain at the site of injection, rather than biodistributing widely, and to clear over time. The results of these safety studies have been submitted to the Food and Drug Administration to support the safety of initiating clinical studies with these and related DNA plasmid vaccines. Thus far, standard repeated-dose toxicology studies have not identified any target organs for toxicity (other than the injection site) for our DNA plasmid vaccines at doses up to 8 mg per immunization, regardless of disease indication (i.e., expressed gene-insert) and despite differences (strengths) in the promoters used to drive this expression. As clinical data accumulate with these products, it will be possible to retrospectively compare the safety profiles of the products in the clinic to the results of the repeated-dose toxicology studies, in order to determine the utility of such toxicology studies for signaling potential immunotoxicities or intrinsic toxicities from DNA vaccines. These data build on the biodistribution studies performed (see companion article, Sheets et al., 2006) to demonstrate the safety and suitability for investigational human use of DNA plasmid vaccine candidates for a variety of infectious disease prevention indications.

The cytotoxic anti-tumor effect of MTH-68/H, a live attenuated Newcastle disease virus is mediated by the induction of nitric oxide synthesis in rat peritoneal macrophages in vitro.

Rat peritoneal macrophages were induced to produce high amounts of nitric oxide (NO) when rats were challenged by MTH68/H, (a live attenuated oncolytic Newcastle disease virus strain). The increase in NO production was observed to be viral particle dose dependent. The higher NO production measured could be due to the enhanced expression of NO synthase II enzyme. In addition, viral administration caused a higher macrophage cell count in the peritoneal cavity of treated rats. Interleukin-1 and granulocyte-monocyte colony stimulating factors were also produced by the induced macrophages. COS 7, a transformed cell line was killed by both NO donors and activated macrophages; the latter effect was markedly decreased in the presence of the inhibitors of NO production. Cytotoxic effect of NO was evidenced by the decrease of cell viability and proliferation of COS 7 cells. Excessive NO production may also be cytotoxic for macrophages themselves as proved by the addition of exogenous NO donors. These results strongly suggested the participation of induced NO synthesis of macrophages in the anti-tumor effect of MTH-68/H vaccine treatment.

The effects of injection of bovine vaccine into a human digit: a case report.

BACKGROUND: The incidence of needlestick injuries in farmers and veterinary surgeons is significant and the consequences of such an injection can be serious. CASE PRESENTATION: We report accidental injection of bovine vaccine into the base of the little finger. This resulted in increased pressure in the flexor sheath causing signs and symptoms of ischemia. Amputation of the digit was required despite repeated surgical debridement and decompression. CONCLUSION: There have been previous reports of injection of oil-based vaccines into the human hand resulting in granulomatous inflammation or sterile abscess and causing morbidity and tissue loss. Self-injection with veterinary vaccines is an occupational hazard for farmers and veterinary surgeons. Injection of vaccine into a closed compartment such as the human finger can have serious sequelae including loss of the injected digit. These injuries are not to be underestimated. Early debridement and irrigation of the injected area with decompression is likely to give the best outcome. Frequent review is necessary after the first procedure because repeat operations may be required.

Combined prime-boost vaccination against tick-borne encephalitis (TBE) using a recombinant vaccinia virus and a bacterial plasmid both expressing TBE virus non-structural NS1 protein.

BACKGROUND: Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol. RESULTS: The heterologous prime-boost vaccination protocol, using a VV recombinant and bacterial plasmid, both containing the NS1 TBE virus protein gene under the control of different promoters, achieved a high level of protection in mice against lethal challenge with a highly pathogenic TBE virus strain. No signs of pronounced TBE infection were detected in the surviving animals. CONCLUSION: Heterologous prime-boost vaccination protocols using recombinant VV and bacterial plasmids could be used for the development of flavivirus vaccines.

Effect of tuftsin on embryo vaccination with Newcastle disease virus vaccine.

The effect of tuftsin of embryo and post-hatch vaccination with NDV-F was studied. The embryo vaccination with NDV-F resulted in more number of dead-in-shell embryos. To overcome this problem, the vaccine was treated separately with ethyl methane sulfate (EMS) and 5-fluorouracil (5-FU) and administered. Treating the vaccine with 5-FU resulted in better hatchability as compared to EMS treatment. In embryo, NDV antibody titres increased upto 2 weeks of age and declined thereafter, whereas in post-hatch vaccination, the antibody titre increased from second to fourth week of age and declined thereafter. The seroconversion was better when the vaccine was given along with tuftsin either to embryos or chicks (post-hatch vaccination) as compared to those vaccinated without tuftsin. Moreover, the percentage of hatchability was more in tuftsin administered groups. It was found that embryo vaccination can ensure definite protection during the early life of the chicks despite the presence of maternal antibodies. In cases where breeder vaccinations do not result in concomitant transfer of antibody to progeny chicks, embryo vaccination would give only neonatal resistance. During the later stages, embryo vaccination did not confer any advantage over post-hatch vaccination.

[Safety and efficacy of attenuated Salmonella typhimurium harbouring DNA vaccine against Newcastle disease virus].

A pair of primers were designed and synthesized according to the previously published sequence of fusion protein (F) gene of Newcastle disease virus (NDV) and used to amplify F gene by reverse-transcription polymerase chain reaction (RT-PCR) from the genomic RNA of a NDV strain JS5 isolated from goose. The PCR product was identified by sequencing. Then recombinant eukaryotic expression vector pVAX1-F was constructed through inserting F gene into MCS of pVAX1. The recombinant plasmid pVAX1-F was transfected in COS-7 cells, and identified for the transient expression of F gene by indirect immunofluorescent assay. Finally, the recombinant plasmid was transformed into attenuated Salmonella typhimurium SL7207, and the recombinant was screened and designated as SL7207 (pVAX1-F). It was verified that SL7207 (pVAX1-F) as the oral NDV DNA vaccine was safe for chickens after oral immunization at dosage of 10(10) CFU or below. 1-day-old commercial ISA brown chickens were immunized orally with SL7207 (pVAX1-F) at two different dosages (10(9) CFU and 10(8) CFU) on day 1, 14 and 28. On day 7 after the last immunization, no significant difference was observed in the body weight between these two groups (p > 0.05), and also no significant difference between those two groups and negative control group (p > 0.05). Since there were maternal antibodies, high ELISA titers of serum antibodies against NDV were detected in the chickens of all groups on day 14. However, the levels of serum antibodies were decreased in the chickens of all groups on day 28, but the anti-NDV antibody response detected in the sera of chickens immunized with SL7207 (pVAX1-F) at the dosage of 10(9) CFU were increased and significantly higher than the response induced by immunization with SL7207 (pVAX1) on day 35 (p < 0.05). Intestinal mucosal immune response was observed in chickens immunized with SL7207 (pVAX1-F) at the dosage of 10(9) CFU or 10(8) CFU. The high ELISA titers of antibodies against NDV in small intestinal mucosal samples from immunized chickens were on day 28 and 35. After challenged intranasally with virulent NDV strain F48E8, the chickens immunized with SL7207 (pVAX1-F) at the dosage of 10(9) CFU could be protected with the protective rate of 77.27%, significantly higher than those with SL7207 (pVAX1) (p < 0.05). In summary, the DNA vaccine delivered by attenuated Salmonella typhimurium was safe and has good immunogenicity for chickens. A novel mucosal DNA vaccine was developed and could be useful for controlling the infection and epidemic of ND in the poultry.

Evaluation in macaques of HIV-1 DNA vaccines containing primate CpG motifs and fowlpoxvirus vaccines co-expressing IFNgamma or IL-12.

Induction of HIV-specific T-cell responses by vaccines may facilitate efficient control of HIV. Plasmid DNA vaccines and recombinant fowlpoxvirus (rFPV) vaccines are promising HIV-1 vaccine candidates, although either vaccine alone may be insufficient to protect against HIV-1. A consecutive immunisation strategy involving priming with DNA and boosting with rFPV vaccines encoding multiple common HIV-1 antigens was further evaluated in 30 macaques. The DNA vaccine vector included CpG immunostimulatory molecules, and rFPV vaccines were compared with rFPV vaccines co-expressing the pro-T cell cytokines IFNgamma or IL-12. Vaccines expressed multiple HIV-1 genes, mutated to remove active sites of the HIV proteins. The vaccines were well tolerated, and a significant enhancement of DNA-vaccine primed HIV-1 specific T lymphocyte responses was observed following rFPV boosting. Co-expression of IFNgamma or IL-12 by the rFPV vaccines did not further enhance immune responses. Non-sterilising protection from a non-pathogenic HIV-1 challenge was observed. This study provides evidence of a safe, optimised, strategy for the generation of T-cell mediated immunity to HIV-1.

Technology evaluation: ChimeriVax-DEN, Acambis/Aventis.

Acambis, in collaboration with Aventis Pasteur, is developing a chimeric vaccine based on a recombinant yellow fever vaccine for the potential prevention of dengue virus infection. The vaccine is undergoing phase I clinical trials.

Enhanced disease and pulmonary eosinophilia associated with formalin-inactivated respiratory syncytial virus vaccination are linked to G glycoprotein CX3C-CX3CR1 interaction and expression of substance P.

Vaccination with formalin-inactivated respiratory syncytial virus (FI-RSV) vaccine or RSV G glycoprotein results in enhanced pulmonary disease after live RSV infection. Enhanced pulmonary disease is characterized by pulmonary eosinophilia and is associated with a substantial inflammatory response. We show that the absence of the G glycoprotein or G glycoprotein CX3C motif during FI-RSV vaccination or RSV challenge of FI-RSV-vaccinated mice, or treatment with anti-substance P or anti-CX3CR1 antibodies, reduces or eliminates enhanced pulmonary disease, modifies T-cell receptor Vbeta usage, and alters CC and CXC chemokine expression. These data suggest that the G glycoprotein, and in particular the G glycoprotein CX3C motif, is key in the enhanced inflammatory response to FI-RSV vaccination, possibly through the induction of substance P.

Enhanced tumour growth after DNA vaccination against human papilloma virus E7 oncoprotein: evidence for tumour-induced immune deviation.

We have examined the induction of anti-tumour immunity in a murine model using a gene vaccine approach to deliver a well defined tumour antigen. The vaccines expressed the human papilloma virus type 16 (HPV 16) E7 oncoprotein, and protection was measured against HPV 16-expressing C3R tumour cell line in vivo. In control mice injected with saline, C3R cells initially formed tumours but then regressed completely. As expected, animals injected with a peptide that represents the D(b)-presented CTL epitope from E7 (RAHYNIVTF) were completely protected from tumour growth. Contrary to expectation, however, we consistently saw enhanced tumour growth, delayed regression, or tumour outgrowth in mice vaccinated with two different E7-expressing DNA vaccines. We found no evidence for loss of D(b) or K(b) class I MHC molecules from C3R cells recovered from outgrown tumours, and fluorescent MHC/peptide tetramer staining revealed E7 gene vaccination did not delete RAHYNIVTF-specific CD8(+) T cells. However, we did observe an effect on cytokine production. Splenocytes from E7 gene vaccinated animals responded to re-stimulation in vitro with C3R cells by producing IL-4 but background levels of IFN-gamma. We also observed that cytokine production and E7 peptide-specific CTL were only detectable in vaccinated animals after C3R challenge, but not after DNA priming alone. We conclude that 'prime-boosting' is necessary to observe tumour-specific T cell responses with the gene vaccine approach, but that boosting with tumour cells causes skewing of the primed cells in a T2 direction that is incompatible with protective anti-tumour immunity.

Phase II clinical trial of intralesional administration of the oncolytic adenovirus ONYX-015 in patients with hepatobiliary tumors with correlative p53 studies.

PURPOSE: ONYX-015 is a genetically modified adenovirus with a deletion of the E1B early gene and is therefore designed to replicate preferentially in p53-mutated cells. A Phase II trial of intralesional ONYX-015 was conducted in patients with hepatobiliary tumors to determine the safety and efficacy of such a treatment. EXPERIMENTAL DESIGN: All patients had biopsy-proven, measurable tumors of the liver, gall bladder, or bile ducts that were beyond the scope of surgical resection. Patients received intralesional injections of ONYX-015 at either 6 x 10(9) or 1 x 10(10) plaque-forming units/lesion up to a total dose of 3 x 10(10) plaque-forming units, and i.p. injections were allowed in patients with malignant ascites. The status of p53 was assessed by immunohistochemistry or Affymetrix GeneChip microarray analysis. Studies were conducted for viral shedding and for the presence of antiadenoviral antibodies before and after the injection of ONYX-015. Patients were assessed for response and toxicity. RESULTS: Twenty patients were enrolled, and 19 patients were eligible. Half of the patients had primary bile duct carcinomas. Serious toxicities (> grade 2) were uncommon and included hepatic toxicity (three patients), anemia (one patient), infection (one patient), and cardiac toxicity (one patient, atrial fibrillation). Sixteen patients were evaluable for response. Among these evaluable patients, 1 of 16 (6.3%) had a partial response, 1 of 16 (6.3%) had prolonged disease stabilization (49 weeks), and 8 of 16 (50%) had a >50% reduction in tumor markers. Of the 19 eligible patients, 18 (94.7%) had specimens available for p53 analysis. Fifteen of these 18 patients (83.3%) had evidence of p53 mutation by one or both methods, although the methods correlated poorly. Viral shedding was confined to bile (two of two patients) and ascites (four of four patients). Pretreatment adenoviral antibodies were present in 14 of 14 patients and increased by 33.2% after ONYX-015 treatment. CONCLUSIONS: Intralesional treatment with ONYX-015 in patients with hepatobiliary tumors is safe and well tolerated, and some patients had evidence of an anticancer effect. The high incidence of p53 mutations in these tumors makes this a logical population in which to test this therapy but precludes definitive evaluation about the necessity of a p53 mutation for ONYX-015 clinical activity.