Biomedical subjects

Juan Morales

Publications and source records attributed to Juan Morales.

12 recordsLinked to original sources

PubMed2006

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.

Amino Acid Sequence↗

PubMed2004

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.

Animals↗

PubMed2004

Late reactivation of tuberculosis in an oleothorax.

The injection of oil into the pleural cavity was a widely used treatment of pulmonary tuberculosis until the advent of effective anti-tuberculous therapy. Long-term complications of oleothorax can occur when the oil is not removed. The authors present an unusual complication of oleothorax, reactivation of tuberculosis, 54 years after oil instillation.

Aged↗

PubMed2004

Frequency domain formulation of active parametric deformable models.

Active deformable models are simple tools, very popular in computer vision and computer graphics, for solving ill-posed problems or mimic real physical systems. The classical formulation is given in the spatial domain, the motor of the procedure is a second-order linear system, and rigidity and elasticity are the basic parameters for its characterization. This paper proposes a novel formulation based on a frequency-domain analysis: The internal energy functional and the Lagrange minimization are performed entirely in the frequency domain, which leads to a simple formulation and design. The frequency-based implementation offers important computational savings in comparison to the original one, a feature that is improved by the efficient hardware and software computation of the FFT algorithm. This new formulation focuses on the stiffness spectrum, allowing the possibility of constructing deformable models apart from the elasticity and rigidity-based original formulation. Simulation examples validate the theoretical results.

Journal Article↗

PubMed2003

Estimating volumetric motion in human thorax with parametric matching constraints.

In radiotherapy (RT), organ motion caused by breathing prevents accurate patient positioning, radiation dose, and target volume determination. Most of the motion-compensated trial techniques require collaboration of the patient and expensive equipment. Estimating the motion between two computed tomography (CT) three-dimensional scans at the extremes of the breathing cycle and including this information in the RT planning has been shyly considered, mainly because that is a tedious manual task. This paper proposes a method to compute in a fully automatic fashion the spatial correspondence between those sets of volumetric CT data. Given the large ambiguity present in this problem, the method aims to reduce gradually this uncertainty through two main phases: a similarity-parametrization data analysis and a projection-regularization phase. Results on a real study show a high accuracy in establishing the spatial correspondence between both sets. Embedding this method in RT planning tools is foreseen, after making some suggested improvements and proving the validity of the two-scan approach.

Algorithms↗

PubMed2002

Improvement of human interferon HUIFNalpha2 and HCV core protein expression levels in Escherichia coli but not of HUIFNalpha8 by using the tRNA(AGA/AGG).

High-level expression from one particular heterologous gene in Escherichia coli generally requires the optimization of codon usage. Genes encoding for Hepatitis C virus core protein (HCcAg), human interferon alpha2 and 8 subtypes (HUIFNalpha2 and HUIFNalpha8) show a high content of AGA/AGG codons. These are encoded by the product of the dnaY gene in E. coli. The proteins used in this work have a high therapeutic value and were used as models for studying the effects of these rare codons on the efficiency of heterologous gene expression in E. coli. Expression plasmids were constructed to express any of these proteins and the dnaY gene product simultaneously in E. coli. After dnaY gene expression, HCcAg, and HUIFNalpha2 expression levels increased 5 and 3 times, respectively. However, HUIFNalpha8 expression was barely detected either supplying or not the additional dnaY gene product. These results suggest that the high frequency of AGA/AGG codons present in the HCcAg and HUIFNalpha2 genes could be one of the factors limiting its expression in E. coli. Nevertheless, for HUIFNalpha8 it seems that other factors prevail upon the lack of dnaY product. Data presented here for HCcAg and HUIFNalpha2 expressions proved the value of this approach to obtain therapeutic proteins in E. coli.

Antiviral Agents↗

PubMed2002

Processing of the Hepatitis C virus precursor protein expressed in the methylotrophic yeast Pichia pastoris.

The expression and processing of the Hepatitis C virus core protein (HCcAg) were analyzed in the methylotrophic yeast Pichia pastoris. Two proteins with 21 (p21) and 23 kDa (p23) were detected in immunoblot with a serum from a chronic carrier patient, as the major products for HCcAg. Both proteins, p21 and p23, produced by proteolytic processing in P. partoris, share the same N-terminal region and reacted with a monoclonal antibody towards the first 35 amino acids of HCcAg. The proteolytic processing of the recombinant polypeptide, having the HCcAg and the first 148 aa of E1 protein, was also confirmed by immunoblot analysis using mAbs with HCcAg and E1 specificities, respectively. The 32 kDa glycosilated E1 protein was then immuno-identified, as well as the processed HCcAg. These data demonstrated the usefulness of P. pastoris, as expression system, to study the processing of HCV structural proteins.

Hepatitis C Antigens↗

PubMed2002

In vitro self-assembled HCV core virus-like particles induce a strong antibody immune response in sheep.

The in vitro self-assembly properties of the entire hepatitis C virus core protein (HCcAg) obtained from Pichia pastoris cells and the induction of specific antibody immune response were studied. HCcAg was purified as a low-molecular-weight species by electroelution under denaturing conditions for confirmation of its self-assembly properties. After renaturalization, electron microscopy showed that HCcAg assembled into spherical particles of 30 nm. HCcAg also showed homogeneity and was specifically recognized by serum from a chronic HCV carrier patient. The data indicated that in vitro assembly of HCcAg, into virus-like particles resembling HCV nucleocapsid particles at a mature stage, is an intrinsic quality of this protein. Finally, HCcAg generated a strong antibody immune response in sheep, suggesting its usefulness for stimulating the host immune response against HCV.

Animals↗

PubMed2002

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.

Animals↗

PubMed2002

Effect of aldose reductase inhibition on interleukin-1beta-induced nitric oxide (NO) synthesis in vascular tissue.

Glucose metabolism via sorbitol pathway has been implicated as a possible contributor to the diabetes-related vascular changes. Nitric oxide plays a major regulatory role in the vascular dilatatory and constricted response. Also it has been observed that diabetes causes vascular changes leading to a decrease in nitric oxide production. Additionally the accumulation of sorbitol is also related to decreased nitric oxide production. In the present study we investigated the effect of normal and high glucose in the presence or absence of both interleukin-1beta or an aldose reductase inhibitor on nitric oxide production in rat aortic rings in vitro. Aortic rings from normal male Wistar rats were dissected and incubated for 24 to 48 hrs in the presence of glucose (5.0 mM or 20 mM) or with or without interleukin (20 ng/ml). Other rings were incubated in the above media with the addition of the aldose reductase inhibitor (WAY 121509). Interleukin-1beta stimulated the 24 hr nitric oxide production and WAY 121509 decreased it under both low and high glucose culture conditions. The interleukin-1beta stimulation was continued for 72 hrs. Nitric oxide production in response to interleukin-1beta was greater at all time points when compared to the incubation in media without interleukin-1beta. In media containing WAY 121509 the nitric oxide production was decreased. Interleukin-1beta stimulated a greater increase in nitric oxide production from aortic rings when incubated in high glucose when compared to normal glucose. The inhibitory effect of aldose reductase inhibition was reversible after 24 hr inhibition under both normal and high glucose conditions. We conclude that high glucose enhances the interleukin-1beta-induced nitric oxide synthesis and the cytokine-induced nitric oxide production was inhibited by aldose reductase inhibition. Nitric oxide production may be linked to redox influences caused by the polyol pathway.

Aldehyde Reductase↗

PubMed2002

Prevalence of oral lesions in Mexican children with perinatally acquired HIV: association with immunologic status, viral load, and gender.

It has been proposed that HIV-related oral lesions (HIV-ROL) have a significant diagnostic and prognostic value for human immunodeficiency virus (HIV) infection in adult patients. However, in HIV-infected children, the relation between HIV-ROL and immune and virologic status is not well established. The principal objective of this paper is to assess the prevalence of HIV-related oral lesions (HIV-ROL) in Mexican HIV-infected children in relation to their immunologic status, viral load, and gender. Forty-eight HIV-infected children from Immunodeficiency Clinic, Child's Hospital of México, México City, were examined for oral pathology. The data obtained from medical records were: name, gender, age, route of infection, CD4 lymphocytes cells count/mL, HIV-1-RNA level of copies/mL (viral load), and type and time of treatment. The prevalence of HIV-ROL was 29.2%. Oral candidosis was the most prevalent oral lesion (20.8%) followed by periodontal and gingival disease (4.2%), herpes simplex (2.1%), and parotid enlargement (2.1%). There was no association between the prevalence of HIV-ROL and gender, immunological status, or viral load. The most frequent clinical form of oral candidosis was erythematous candidosis (12.5%, N = 6). Our results do not suggest a direct relationship between prevalence of HIV-ROL, severe immunodepression, and/or viral load > 100000 copies in this population.

AIDS-Related Opportunistic Infections↗

PubMed2002

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.

Animals↗