Plant expressed EtMIC2 is an effective immunogen in conferring protection against chicken coccidiosis

Coccidiosis is an economically important disease affecting poultry industry and remains one of the major problems globally. Developing a cost effective sub-unit vaccine may help mitigate loss in the industry. Here, we report expressing one of the microneme proteins, EtMIC2 from Eimeria tenella in tobacco using Agrobacterium-mediated transient expression. The ability of plant expressed recombinant EtMIC2 in eliciting both humoral and cell-mediated immune responses were measured in the immunized birds. The protective efficacy in the vaccinated birds against a homologous challenge was also evaluated. Birds immunized with plant expressed EtMIC2 showed good sero-conversion, reduced oocyst output and increased weight gain when compared to control birds. Our data indicate that use of plant expressed recombinant EtMIC2 in birds was safe and had the potential in imparting partial protection in chickens against homologous challenge.

Expression of codon optimized major capsid protein (L1) of human papillomavirus type 16 and 18 in Pichia pastoris; purification and characterization of the virus-like particles

The major capsid protein (L1) of human papillomaviruses (HPV) expressed in heterologous systems assembles into virus-like particles (VLPs). We report cloning and expression of codon optimized HPV L1 genes of the two high-risk HPV types 16 and 18 in methylotropic yeast, Pichia pastoris. The VLPs produced in P. pastoris were subjected to three step purification method involving density gradient centrifugations and size exclusion chromatography. The enriched VLPs were characterized using conformation-specific monoclonal antibodies in ELISA and by transmission electron microscopy. Mice immunized with a bivalent HPV16 and HPV18 VLPs developed high serum antibody titers to both HPV types that persisted for 190 days post vaccination. Serum of mice immunized with the HPV-VLP preparations could neutralize homologous pseudoviruses in an in vitro assays. Our results demonstrate that the L1 proteins expressed in P. pastoris fold properly as evidenced by assembly into VLPs and induction of type-specific neutralizing antibody response in mice. This work constitutes a step towards developing an alternate production platform for generating an affordable HPV vaccine to meet the needs of developing countries.

Eimeria maxima recombinant Gam82 gametocyte antigen vaccine protects against coccidiosis and augments humoral and cell-mediated immunity (46.19)

Intestinal infection with Eimeria, the etiologic agent of avian coccidiosis, stimulates protective immunity to subsequent colonization by the homologous parasite, whilst cross-protection against heterologous species is poor. This study was designed to assess a purified recombinant protein from E. maxima gametocytes (Gam82) in stimulating immunity against experimental infection with live parasites. Following Gam82 intramuscular immunization and oral parasite challenge, body weight gain, fecal oocyst output, gut lesions, serum antibody response, cytokine production, and lymphoproliferation were assessed to evaluate vaccination efficacy. Animals vaccinated with Gam82 and challenged with E. maxima showed lower oocyst shedding and reduced intestinal pathology compared with non-vaccinated and parasite-challenged animals. Gam82 vaccination also stimulated the production of antigen-specific serum antibodies, induced greater levels of IL-2 and IL-15 mRNAs, and increased splenic lymphoproliferation compared with non-vaccinated controls. These results demonstrate that the Gam82 recombinant protein protects against coccidiosis and augments humoral and cell-mediated immunity.

Eimeria maxima recombinant Gam82 gametocyte antigen vaccine protects against coccidiosis and augments humoral and cell-mediated immunity

Intestinal infection with Eimeria, the etiologic agent of avian coccidiosis, stimulates protective immunity to subsequent colonization by the homologous parasite, while cross-protection against heterologous species is poor. As a first step toward the development of a broad specificity Eimeria vaccine, this study was designed to assess a purified recombinant protein from Eimeria maxima gametocytes (Gam82) in stimulating immunity against experimental infection with live parasites. Following Gam82 intramuscular immunization and oral parasite challenge, body weight gain, fecal oocyst output, lesion scores, serum antibody response, and cytokine production were assessed to evaluate vaccination efficacy. Animals vaccinated with Gam82 and challenged with E. maxima showed lower oocyst shedding and reduced intestinal pathology compared with non-vaccinated and parasite-challenged animals. Gam82 vaccination also stimulated the production of antigen-specific serum antibodies and induced greater levels of IL-2 and IL-15 mRNAs compared with non-vaccinated controls. These results demonstrate that the Gam82 recombinant protein protects against E. maxima and augments humoral and cell-mediated immunity.

The insulin sensitiser pioglitazone does not influence skin microcirculatory function in patients with type 2 diabetes treated with insulin

AIMS/HYPOTHESIS

Insulin resistance is associated with abnormal microvascular function. Treatment with insulin sensitisers may provoke oedema, suggesting microvascular effects. The mechanisms underlying the peripheral oedema observed during glucose-lowering treatment with thiazolidinediones are unclear. Therefore we examined the effect of pioglitazone on microvascular variables involved in oedema formation.

METHODS

Subjects (40-80 years) with type 2 diabetes and on insulin were randomised to 9 weeks of pioglitazone therapy (30 mg/day; n=14) or placebo (n=15). The following assessments were performed at baseline and 9 weeks: microvascular filtration capacity; isovolumetric venous pressure; capillary pressure; capillary recruitment following venous or arterial occlusion; postural vasoconstriction; and maximum blood flow. A number of haematological variables were also measured including vascular endothelium growth factor (VEGF), IL-6 and C-reactive protein (CRP).

RESULTS

Pioglitazone did not significantly influence any microcirculatory variable as compared with placebo (analysis of covariance [ANCOVA] for microvascular filtration capacity for the two groups, p=0.26). Mean VEGF increased with pioglitazone (61.1 pg/ml), but not significantly more than placebo (9.76 pg/ml, p=0.94). HbA(1c) levels and the inflammatory markers IL-6 and CRP decreased with pioglitazone compared with placebo (ANCOVA: p=0.009, p=0.001 and p=0.004, respectively).

CONCLUSIONS/INTERPRETATION

Pioglitazone improved glycaemic control and inflammatory markers over 9 weeks but had no effect on microcirculatory variables associated with oedema or insulin resistance in type 2 diabetic patients treated with insulin.

Efficacy of plant-produced recombinant antibodies against HCG

BACKGROUND

Antibody engineering facilitates the construction of different antibody formats [single chain variable fragment (scFv), diabody, full-size chimeric monoclonal antibody] with ease.

METHODS

We constructed recombinant antibodies against HCG, which is widely used in pregnancy testing and is also produced by a number of cancers.

RESULTS

The recombinant antibodies were transiently expressed in tobacco leaves to levels of up to 40 mg of pure protein per kg fresh leaf weight. Enzyme linked immunosorbent assay (ELISA) and electrophoretic mobility assay (EMSA) confirmed antibody specificity for the beta subunit of beta-HCG. The efficacy was confirmed by inhibiting HCG induced testosterone production by Leydig cells in vitro and by blocking the HCG induced increase in mouse uterine weight in vivo.

CONCLUSIONS

Passive immunization with recombinant HCG-specific antibodies may have clinical utility as (i) diagnostic and therapeutic tools for HCG-expressing cancers and (ii) contraceptive measures.

Effect of combined kinetic therapy and percussion therapy on the resolution of atelectasis in critically ill patients

BACKGROUND

Some critically ill patients have difficulty in mobilizing their respiratory secretions. These patients can develop pulmonary atelectasis that may result in hypoxemia. There are some data to show that atelectasis may be prevented by turning a patient from side to side utilizing special beds.

STUDY OBJECTIVES

To determine the role of kinetic therapy (KT) combined with mechanical percussion (P) in the resolution of established atelectasis of the lungs and hypoxemia in critically ill, hospitalized patients. (KT was defined as rotation of a patient along the longitudinal axis of > or = 40 degrees to each side continuously.)

DESIGN

Prospective and randomized study (2:1 test to control group).

PATIENTS

Twenty-four patients with respiratory failure, either mechanically ventilated or spontaneously breathing, who demonstrated segmental, lobar, or unilateral entire lung atelectasis were studied.

SETTING

Medical ICU and adult respiratory ward in a county hospital in New York.

INTERVENTIONS

Seventeen patients were treated with KT combined with mechanical P using a KT system (Triadyne Kinetic Therapy System; KCI; San Antonio, TX). Seven patients received manual repositioning and manual P every 2 h. Both groups received similar conventional therapy with inhaled bronchodilators and suctioning.

RESULTS

Partial or complete resolution of atelectasis was seen in 14 of 17 patients (82.3%) in the test group as compared with 1 of 7 patient (14.3%) in the control group. The median duration to resolution of atelectasis was 4 days in the test group. Bronchoscopy was performed in 3 of 7 patients in the control group, but in none of the patients in the test group. A cost of $720 was incurred per patient for utilizing the specialty beds for a mean duration of 4 days. An improvement in oxygenation index occurred in the test group (change in baseline PaO2/fraction of inspired oxygen from 207.4+/-106.7 mm Hg to 318+/-100.7 mm Hg) at the end of therapy, while the control group showed a reduction over a similar duration of time (181.3+/-96.3 mm Hg to 112+/-21.2 mm Hg).

CONCLUSIONS

KT and mechanical P therapy resulted in significantly greater partial or complete resolution of atelectasis as compared with conventional therapy. There was a generalized trend toward statistical significance in the improvement of oxygenation and a reduced need for bronchoscopy in the group receiving KT and P therapy.