NeuroEPO plus (NeuralCIM®) in mild-to-moderate Alzheimer's clinical syndrome: the ATHENEA randomized clinical trial.

BACKGROUND: NeuroEPO plus is a recombinant human erythropoietin without erythropoietic activity and shorter plasma half-life due to its low sialic acid content. NeuroEPO plus prevents oxidative damage, neuroinflammation, apoptosis and cognitive deficit in an Alzheimer's disease (AD) models. The aim of this study was to assess efficacy and safety of neuroEPO plus. METHODS: This was a double-blind, randomized, placebo-controlled, phase 2-3 trial involving participants ≥ 50 years of age with mild-to-moderate AD clinical syndrome. Participants were randomized in a 1:1:1 ratio to receive 0.5 or 1.0 mg of neuroEPO plus or placebo intranasally 3 times/week for 48 weeks. The primary outcome was change in the 11-item cognitive subscale of the AD Assessment Scale (ADAS-Cog11) score from baseline to 48 weeks (range, 0 to 70; higher scores indicate greater impairment). Secondary outcomes included CIBIC+, GDS, MoCA, NPI, Activities of Daily Living Scales, cerebral perfusion, and hippocampal volume. RESULTS: A total of 174 participants were enrolled and 170 were treated (57 in neuroEPO plus 0.5 mg, 56 in neuroEPO plus 1.0 mg and 57 in placebo group). Mean age, 74.0 years; 121 (71.2%) women and 85% completed the trial. The median change in ADAS-Cog11 score at 48 weeks was -3.0 (95% CI, -4.3 to -1.7) in the 0.5 mg neuroEPO plus group, -4.0 (95% CI, -5.9 to -2.1) in the 1.0 mg neuroEPO plus group and 4.0 (95% CI, 1.9 to 6.1) in the placebo group. The difference of neuroEPO plus 0.5 mg vs. placebo was 7.0 points (95% CI, 4.5-9.5) P = 0.000 and between the neuroEPO plus 1.0 mg vs. placebo was 8.0 points (95% CI, 5.2-10.8) P = 0.000. NeuroEPO plus treatment induced a statistically significant improvement in some of clinical secondary outcomes vs. placebo including CIBIC+, GDS, MoCA, NPI, and the brain perfusion. CONCLUSIONS: Among participants with mild-moderate Alzheimer's disease clinical syndrome, neuroEPO plus improved the cognitive evaluation at 48 weeks, with a very good safety profile. Larger trials are warranted to determine the efficacy and safety of neuroEPO plus in Alzheimer's disease. TRIAL REGISTRATION: https://rpcec.sld.cu Identifier: RPCEC00000232.

Toxicology and biodistribution study of CIGB-230, a DNA vaccine against hepatitis C virus.

CIGB-230, a mixture of a DNA plasmid expressing hepatitis C virus (HCV) structural antigens and a HCV recombinant capsid protein, has demonstrated to elicit strong immune responses in animals. The present study evaluated the plasmid biodistribution after the administration of CIGB-230 in mice, as well as toxicity of this vaccine candidate in rats. In the biodistribution study, mice received single or repeated intramuscular injections of CIGB-230, 50 microg of plasmid DNA mixed with 5 microg of Co.120 protein. Plasmid presence was assessed in ovaries, kidney, liver, pancreas, mesenteric ganglion, blood, and muscle of the injection site by a qualitative polymerase chain reaction. The toxicology evaluation included treatment groups receiving doses 5, 15, or 50 times higher, according to the body weight, than the expected therapeutic clinical dose. During the first hour after repeated inoculation, a promiscuous distribution was observed. However, 3 months later, plasmid could not be detected in any tissue. There was an absence of detectable adverse effects on key toxicology parameters and no damage evidenced in inspected organs and tissues. These results indicate that CIGB-230 is nontoxic at local and systemic levels and no concerns about persistence are observed, which support clinical testing of this vaccine candidate against HCV.

Expression and processing of hepatitis C virus structural proteins in Pichia pastoris yeast.

Development of heterologous systems to produce useful HCV vaccine candidates is an important part of HCV research. In this study different HCV structural region variants were designed to express the first 120 aa, 176 aa, 339 aa, and 650 aa of HCV polyprotein, and aa 384 to 521, or aa 384-605 or aa 384-746 of HCV E2 protein fused to the leader sequence of sucrose invertase 2 allowing the secretion of recombinant E2 proteins. Low expression levels were observed for HCV core protein (HCcAg) variants expressing the first 120 aa and 176 aa (HCcAg.120 and HCcAg.176, respectively). Higher expression levels were observed when HCcAg was expressed as a polypeptide with either E1 or E1 and E2 proteins. In addition, HCcAg was processed to produce two antigenic bands with 21 and 23kDa (P21 and P23, respectively) when expressed as a polypeptide with HCV E1 and E2 proteins. Results also suggest E1 processing in the context of HCcAg.E1.E2 polyprotein. On the other hand, E2.521, E2.605, and E2.680 were efficiently excreted to the culture medium. However, the entire E2.746 variant predominantly localized in the insoluble fraction of ruptured cells. Results suggest that the hydrophobic C-terminal E2 region from aa 681 to 746 is critical for intracellular retention of recombinant E2.746 protein in Pichia pastoris cells. Endo H or PNGase F treatment suggests that E2.746 was modified with high-mannose type oligosaccharides in P. pastoris. These data justify the usefulness of P. pastoris expression system to express HCV structural viral proteins which may be useful targets for HCV vaccine candidates.

Hepatitis C virus (HCV) core protein enhances the immunogenicity of a co-delivered DNA vaccine encoding HCV structural antigens in mice.

In the present study, recombinant HCV (hepatitis C virus) core proteins enhanced the immune response elicited by a co-delivered DNA vaccine encoding HCV core and envelope proteins. A mixture of the plasmid pIDKE2 and Co.173, a protein comprising the first 173 amino acids of HCV core, in particular induces a strong humoral response, including antibodies that recognized peptides representing hypervariable region I from different viral isolates. Moreover, positive lymphoproliferative responses against the HCV structural proteins, encoded by the plasmid, were detected after two doses with this mixture. When the HCV core protein used in the mixture with pIDKE2 was Co.120, a protein comprising the first 120 amino acids of the viral antigen, a strong humoral response and a positive lymphoproliferative response were also detected. The effectiveness of this formulation was tested in vivo by measuring the protection against infection with a recombinant vaccinia virus expressing HCV core protein. A 2 log reduction in vaccinia-virus titre was observed in mice immunized with the mixture of pIDKE2 and Co.120. Humoral and cellular immune responses elicited for the mixture of pIDKE2 with either Co.173 or Co.120 was stronger and more diverse than those generated by individual components. In conclusion, our results indicate that formulations comprising both DNA constructs and protein subunit vaccine candidates are able to elicit strong humoral and cellular immunity against several antigens. Particularly, HCV core protein might be used as a feasible vehicle/adjuvant for DNA vaccines.

HCV core protein localizes in the nuclei of nonparenchymal liver cells from chronically HCV-infected patients.

Understanding the mechanism of hepatitis C virus (HCV) pathogenesis is an important part of HCV research. Recent experimental evidence suggests that the HCV core protein (HCcAg) has numerous functional activities. These properties suggest that HCcAg, in concert with cellular factors, may contribute to pathogenesis during persistent HCV infection. HCV is capable of infecting cells other than hepatocytes. Although the extrahepatic cellular tropism of HCV may play a role in the pathophysiology of this infection, the precise biological significance of the presence of HCV components in different liver cell types presently remains to be established. In this study, HCcAg was detected in nonparenchymal liver cells of six patients out of eight positive for serum HCV RNA. Immunostaining with anti-HCcAg mAbs revealed the presence of this protein in different liver cell types such as lymphocytes, Kupffer, polymorphonuclear, pit, endothelial, stellate, and fibroblast-like cells. Interestingly, HCcAg was immunolabeled not only in the cytoplasm but also in the nucleus of these cells. Remarkably, HCcAg co-localized with large lipid droplets present in stellate cells and with collagen fibers in the extracellular matrix. Moreover, HCcAg was immunolabeled in bile canaliculus suggesting the involvement of the biliary system in the pathobiology of HCV. Data suggest that nonparenchymal liver cells may constitute a reservoir for HCV replication. Besides, HCcAg may contribute to modulate immune function and fibrosis in the liver as well as steatosis.

Immunization with a DNA vaccine encoding the hepatitis-C-virus structural antigens elicits a specific immune response against the capsid and envelope proteins in rabbits and Macaca irus (crab-eating macaque monkeys).

In the present study, we evaluated the capability of the plasmid pIDKE2, encoding the HCV (hepatitis C virus) structural proteins Core, E1 and E2, to induce immune response against HCV antigens after injection into rabbits and Macaca irus (crab-eating macaque). Animals were immunized intramuscularly with different amounts of plasmid on weeks 0, 3 and 8. Monkeys received a booster dose on week 46. All rabbits immunized with pIDKE2 generated a positive antibody response and, particularly in rabbits immunized with 2 mg, antibody titres reached values above 1:1500 and 1:400 against the core and the envelope proteins, respectively, 28 weeks after primary immunization. The antibody response in monkeys developed slowly, but antibody titres greater than 1:3500 against HCV structural antigens were detected at week 52. Moreover, anti-E2 antibodies recognized synthetic peptides covering the HVR-1 (hypervariable region-1) from different isolates corresponding to different genotypes. Additionally, a specific lymphoproliferative response against Core and E2 was detected in two out of three monkeys immunized with pIDKE2. The other monkey had a specific proliferative response to E1. Taking all these data together, immunization with pIDKE2 is able to elicit both humoral and cellular immunity against HCV structural antigens in animal models other than mice.

Ultrastructural evidences of HCV infection in hepatocytes of chronically HCV-infected patients.

In this study, 13 samples of liver biopsies from patients with chronic hepatitis C were studied by transmission electron microscopy (EM) and immunoelectron microscopy (IEM). The 13 biopsies showed ultrastructural cell damage typical of acute viral hepatitis. In four of the 13 liver biopsies enveloped virus-like particles (VLPs) inside cytoplasmic vesicles and in the cytoplasm of hepatocytes were observed. We also detected the presence of unenveloped VLPs mainly in the cytoplasm and in the endoplasmic reticulum. IEM using anti-core, E1 and E2 monoclonal antibodies (mAbs) confirmed the specific localization of these proteins, in vivo, inside cytoplasm and endoplasmic reticulum. Thus, this work provided evidence for hepatocellular injury related to HCV infection. It also suggested the presence of HCV-related replicating structures in the cytoplasm of hepatocytes and raised the possibility of hepatitis C virion morphogenesis in intracellular vesicles.

Enhancement of the immune response generated against hepatitis C virus envelope proteins after DNA vaccination with polyprotein-encoding plasmids.

Plasmids expressing variants of the hepatitis C virus (HCV) core, E1 and E2 proteins individually or as polyproteins were administered to BALB/c mice. All plasmids induced a detectable and specific antibody response. Antibody titres against core, E1 and E2 proteins, 19 weeks after primary immunization, ranged from 1:50 to 1:4500 depending on the inoculated plasmid and the HCV antigen evaluated. Constructs expressing HCV envelope proteins as polyprotein variants including the core amino acid region induced statistically stronger antibody responses than plasmids encoding individual E1 and E2 proteins. Particularly, the pIDKE2 plasmid, expressing the first 650 amino acids in the viral polyprotein, induced a potent and multispecific antibody and lymphoproliferative response against HCV core, E1 and E2 proteins. Anti-E2 antibodies generated by pIDKE2 immunization were cross-reactive to hypervariable region-1 peptides from different genotypes. Immunization with the pIDKE2 also generated a positive cellular immune response against the core antigen, determined by interferon-gamma enzyme-linked immunospot (ELISPOT) assay, and induced detectable levels of interferon-gamma but not interleukin-4 in vaccinated mice. The detection of both antibody and cytotoxic T-lymphocyte responses, potentially targeted to circulating or cell-infecting virions respectively, in mice vaccinated with the pIDKE2 plasmid is very attractive for the effective eradication of HCV infection.

Additives and protein-DNA combinations modulate the humoral immune response elicited by a hepatitis C virus core-encoding plasmid in mice.

Humoral and cellular immune responses are currently induced against hepatitis C virus (HCV) core following vaccination with core-encoding plasmids. However, the anti-core antibody response is frequently weak or transient. In this paper, we evaluated the effect of different additives and DNA-protein combinations on the anti-core antibody response. BALB/c mice were intramuscularly injected with an expression plasmid (pIDKCo), encoding a C-terminal truncated variant of the HCV core protein, alone or combined with CaCl2, PEG 6000, Freund's adjuvant, sonicated calf thymus DNA and a recombinant core protein (Co. 120). Mixture of pIDKCo with PEG 6000 and Freund's adjuvant accelerated the development of the anti-core Ab response. Combination with PEG 6000 also induced a bias to IgG2a subclass predominance among anti-core antibodies. The kinetics, IgG2a/IgG1 ratio and epitope specificity of the anti-core antibody response elicited by Co. 120 alone or combined with pIDKCo was different regarding that induced by the pIDKCo alone. Our data indicate that the antibody response induced following DNA immunization can be modified by formulation strategies.

Additives and protein-DNA combinations modulate the humoral immune response elicited by a hepatitis C virus core-encoding plasmid in mice

Humoral and cellular immune responses are currently induced against hepatitis C virus (HCV) core following vaccination with core-encoding plasmids. However, the anti-core antibody response is frequently weak or transient. In this paper, we evaluated the effect of different additives and DNA-protein combinations on the anti-core antibody response. BALB/c mice were intramuscularly injected with an expression plasmid (pIDKCo), encoding a C-terminal truncated variant of the HCV core protein, alone or combined with CaCl2, PEG 6000, Freund's adjuvant, sonicated calf thymus DNA and a recombinant core protein (Co.120). Mixture of pIDKCo with PEG 6000 and Freund's adjuvant accelerated the development of the anti-core Ab response. Combination with PEG 6000 also induced a bias to IgG2a subclass predominance among anti-core antibodies. The kinetics, IgG2a/IgG1 ratio and epitope specificity of the anti-core antibody response elicited by Co.120 alone or combined with pIDKCo was different regarding that induced by the pIDKCo alone. Our data indicate that the antibody response induced following DNA immunization can be modified by formulation strategies