Ex-vivo evaluation of the mucoadhesive properties of Cedrela odorata and Khaya senegalensis gums with possible applications for veterinary vaccine delivery

Development of cashew-alginate microbeads and powdered dose forms: prospects for oral vaccine delivery in chickens

Conventional oral vaccine delivery in poultry is challenging due to vaccine degradation in the gastrointestinal (GI) environment and the need for cold-chain storage. Microencapsulation offers a solution by protecting vaccines from GI degradation and improving stability. Natural polymers like alginate and cashew gum have mucoadhesive properties, making them promising candidates for oral vaccine delivery. This study developed cashew-alginate microbeads and a powdered dose form for oral vaccine delivery in chickens. The microbeads were created using ionotropic gelation, while the powdered form was obtained via freeze-drying. These formulations were characterized for size, shape, and stability using scanning electron microscopy (SEM), light microscopy, X-ray diffraction (XRD), and Energy Dispersive X-ray (EDX). Peak adhesion time (PAT) was determined using chicken intestinal and esophageal tissues, and antigenicity was assessed with in-vitro hemagglutination (HA) and hemagglutination inhibition (HI) assays. The microbeads exhibited a spherical shape with a porous structure, suggesting enhanced antigen accommodation. Hemagglutination Inhibition tests indicated that the experimental vaccine remained effective without cold-chain storage for three months. These findings suggest that cashew-alginate microbeads are promising for oral vaccine delivery in poultry.

Nanoparticles of Thiolated Xanthan Gum for the Oral Delivery of Miconazole Nitrate: In Vitro and In Vivo Evaluation

The objective of this research was to develop a mucoadhesive delivery system that improves permeation for the administration of poorly absorbed oral medications. Thiolation of xanthan gum (XGM) was carried out by esterification with mercaptobutyric acid. Fourier-transformed infrared spectroscopy was used to confirm thiol-derivatization. Using Ellman's technique, it was revealed that the xanthan-mercaptobutyric acid conjugate had 4.7 mM of thiol groups in 2 mg/mL of polymeric solution. Using mucosa of sheep intestine, the mucoadhesive properties of XGM and thiolated xanthan gum (TXGM) nanoparticles were investigated and we found that TXGM had a longer bioadhesion time than XGM. The disulfide link that forms between mucus and thiolated XGM explains why it has better mucoadhesive properties than XGM. A study on in vitro miconazole (MCZ) release using phosphate buffer (pH 6.8) found that TXGM nanoparticles released MCZ more steadily than MCZ dispersion did. A 1-fold increase in the permeation of MCZ was observed from nanoparticles using albino rat intestine compared to MCZ. Albino rats were used to test the pharmacokinetics of MCZ, and the results showed a 4.5-fold increase in bioavailability. In conclusion, the thiolation of XGM enhances its bioavailability, controlled release of MCZ for a long period of time, and mucoadhesive activity.

Effects of Boswellia species on viral infections with particular attention to SARS-CoV-2

The emergence of pathogenic viruses is a worldwide frequent cause of diseases and, therefore, the design of treatments for viral infections stands as a significant research topic. Despite many efforts, the production of vaccines is faced with many obstacles and the high rate of viral resistance caused a severe reduction in the efficacy of antiviral drugs. However, the attempt of developing novel natural drugs, as well as the exertion of medicinal plants, may be an applicable solution for the treatment of viral diseases. Boswellia species exhibited a wide range of pharmacological activities in various conditions such as bronchial asthma, rheumatism, and Crohn’s illness. Additionally, pharmacological studies reported the observance of practical antiviral activities from different parts of this substance, especially the oleo-gum-resin. Therefore, this work provided an overview on the antiviral properties of Boswellia species and their potential therapeutic effects in the field of COVID-19 pandemic.

Evaluation of oral phytogenic microbeaded Newcastle Disease vaccine delivery in indigenous chicken

This study describes the evaluation of microbeaded oral vaccine delivery for Newcastle Disease (ND) in village chicken. Microbeads containing vaccine were prepared by ionotropic-gelation technique using aluminum sulfate. Lasota Vaccine strain (2 g) was well mixed with Boswellia caterii gum extract at ratio 1:1. The wet beads were washed twice with distilled water and dried at 37℃ overnight. Microbeads without vaccine were prepared as control. A tablet dissolution machine was used to evaluate peak adhesion time (PAT). Sixty local chickens sourced from a recognized breeder were separated into four groups for in in-vivo evaluation. Group A was administered with the bead-loaded vaccine mixed with their feed, group B had vaccine alone administered in their drinking water, group C had the bead alone mixed with their feed, and group D, which served as negative control received no vaccination against ND nor gum beads.The PAT on both trachea and jejunum was 4 ± 10 hours. Post-vaccination antibody titer revealed higher response in group B than (6.6) in group A (5.3); the micro-beaded vaccine gave delayed but enhanced and prolonged immune response. This noninvasive and easy to administer method may be useful in the prevention of ND outbreaks in backyard poultry production.

Screening of polysaccharides from fruit pulp of Ziziphus mauritiana L. and Artocarpus heterophyllus L. as natural mucoadhesives

Background

Mucoadhesive polymers are applicable for improving the delivery of drug by prolonging the residence time and time of contact of the dosage form with the mucous membrane. Mucoadhesion may be defined as a process where the polymer substance gets adhered either to the biological substrate or synthetic or to a natural macromolecule, or to the mucus membrane. The natural polymers can be studied to determine whether they possess some mucoadhesive properties as several excipients derived from plants have proved their potential in the field of conventional or novel dosage form. The present work aims at determination of physical properties of polysaccharides from fruit pulp of Ziziphus mauritiana L. (ZM gum) and Artocarpus heterophyllus L. (AH gum), such as mucoadhesive strength (shear stress determination), swelling index, pH, viscosity, angle of repose, Carr’s index, density, and its comparative study with synthetic polymers Carbopol 934 and HPMC and also to study its FTIR and 1H-NMR spectra analysis.

Result

The most important properties such as mucoadhesive strength of ZM gum (3% w/v) and AH gum (3%) was found to be comparable with HPMC (3% w/v) and Carbopol 934 (3% w/v); also, the swelling index of the isolated gums were also found comparable with both HPMC and Carbopol 934. Falling sphere method is conducted in which the time taken by the sphere to move 50 divisions to the bottom for 3% w/v ZM gum solution was 10.14 s and for AH gum was 10.13 s which is comparable to HPMC and Carbopol 934. The FTIR & 1H NMR spectra showed typical characteristic signals of polysaccharides and presence of typical sugar residues.

Conclusion

From the study, it can be concluded that ZM and AH gum has potential to be better than Carbopol 934 and HPMC in respect of mucoadhesive strength and also it has the potential to replace some synthetic mucoadhesive polymers and polysaccharides.

Intranasal Peste des petits ruminants virus vaccination of goats using Irvingia gabonensis gum as delivery system: hematological and humoral immune responses

Peste des petits ruminants (PPR) in Africa continues to defy conventional vaccinational approaches aimed at its control. There is need for route modification and immunopotentiation of the current vaccination methods, using easily affordable materials. This study evaluates the immunomodulatory potential of Irvingia gabonensis (IG) seed gum extract for intranasal PPR vaccination in goats using attenuated Nigeria 75/1 PPR vaccine. Twenty West African dwarf goats were divided into four groups (n=5). Group 1 was vaccinated intranasally using IG gum as vehicle; Group 2 was vaccinated intranasally without the gum; Group 3 via subcutaneous injection while Group 4 was not vaccinated. Hematology and Serum IgG levels were assessed weekly for 28 days post vaccination (dpv). H-PPR bELISA detected antibodies against PPR by 7th dpv, peaking by 21st dpv with mean percentage inhibitions of 78.2%; 69.6%; 87.0% and 0% in Groups 1, 2, 3 and 4, respectively. Also, significantly lower neutrophil to lymphocyte ratio (P<0.05) were observed by 14th dpv to 28th dpv in the vaccinated groups. The findings of this study show that the use of I. gabonensis seed gum extract for mucoadhesive intranasal PPR vaccine delivery has an immunomodulatory effect on the systemic immune response following PPR intranasal vaccine administration.

Evaluation of mucoadhesive property and the effect of Boswellia carteri gum on intranasal vaccination against small ruminant morbillivirus infection (PPR)

A study was conducted to evaluate mucoadhesive property and immunomodulatory effect of phytogenic gums from Boswellia frereana, Boswellia carteri andCommiphora myrrha on intranasal Peste des petits ruminants (PPR) vaccination in goats and sheep in an ex-vivo and in-vivo situations. Plant gums were purified, dried and compressed into 500gm tablets. Modified shear stress measurement technique was used on freshly excised trachea and intestine tissues of goat to measure peak adhesion time. Forty eight animals (24 goats and 24 sheep) were divided into eight groups (of 3 goats and 3 sheep) and immunized intranasally with gum-vaccine combinations in two ratios (1:1, 1:2). Antibody against PPR virus was measured on day 14, 28, 42 and 56 post vaccination using H-based PPR bELISA. The peak adhesion time of the different gums was transient. PPR virus antibodies were detected in all immunized goats and sheep but not in unvaccinated control. The best percentage inhibition was recorded for Boswellia carteri-vaccine combination group at a ratio of 1:1. Administration of Boswellia carteri-PPR vaccine combination through intranasal or subcutaneous route, elicited similar antibody titre, implying that the intranasal route may be used as a non-invasive alternative delivery in PPR vaccination of small ruminants.

Evaluation of the mucoadhesive strengths of Abelmoschus esculentus and Irvingia gabonensis gums for possible application in veterinary vaccine delivery: the effect of extraction methods

This study evaluates the effects of different gum extraction methods on the mucoadhesive strengths of Abelmoschus esculentus (AE) and Irvingia gabonensis (IG) gums and the release of vaccine antigen in vaccine-gum formulations. AE and IG gums were extracted employing previously documented methods with acetone or sodium chloride (NaCl) and either oven-dried or freeze-dried. Gum extracts were analyzed for mucoadhesive strengths using a modified rotational cylinder method on animal mucosa. The time taken to detach from the mucosa was taken as the Peak Adhesion Time (PAT). The gum extracts were charged with Peste des petits ruminant vaccine and the antigen release was evaluated using agar gel immunodiffusion technique. The means of the PATS were analyzed using Mann-whitney t-test at p < .05. The NaCl extracted and freeze-dried IG gum showed sustained mean PATs of 1766 ± 73 s; 2116 ± 101 s; 7044 ± 117 s, while the oven-dried IG gum and both AE gums showed short-lived average PATs. Vaccine-gum formulations of IG at ratios 2:1, 1:1 & 1:2 had strong positive reactions while only that of AE at 2:1 showed a strong positive reaction. This study shows that NaCl extracted and freeze-dried IG gum has immunomodulatory potential for mucoadhesive vaccine delivery in ruminants.

Humoral and mucosal immune responses in challenged chickens vaccinated with Infectious bursal disease vaccine using gums from Cedrela odorata and Khaya senegalensis as delivery agents

The emergence of antigenic variants and very virulent strains of infectious bursa disease virus (IBDV) in vaccinated flocks considerably stimulated research in IBDV vaccine administration. The mucoadhesive and immunopotentials of Cedrela odorata and Khaya senegalensis were explored in vaccine delivery against clinical IBDV in broiler chickens. A total of 400 chicks were successfully brooded and raised from day old for commencement of this experiment. The birds were randomly distributed into eight groups with an average of 50 birds per group comprising: Gums-Gumboro Vaccine Ocular (infected) (GGVOC), Gumboro Vaccine alone Ocular (infected) (GVOC), Gums alone Ocular (infected) (GOC), Gums-Gumboro Vaccine Oral (infected) (GGVOR), Gumboro Vaccine alone Oral (infected) (GVOR), Gums alone Oral (infected) (GOR), No-Vaccine-No-Gums (infected) (NVNG/i), and No-Vaccine-No-Gums (not infected) (NVNG). On a weekly basis, 1.5mls of blood were collected from 5 birds and 3 birds euthanized per group for serological analysis and mucosal washings (trachea and intestine) respectively. Data obtained were analyzed and sample to positive ratio calculated. The post 1st vaccination trachea IgG antibody response was moderately higher in the ocular groups than the oral groups. It was also high in the VOC, GVOC, GOC, VOR groups than the GVOR groups. The antibody response (IgG) pre and post 1st vaccination, post 2nd vaccination and post infection from serum, trachea and intestinal washes showed that by week 1 Post 1st vaccination, there was insignificant increase in titer serum response of the gum-vaccine ocular group compared to the vaccine ocular alone while both groups were insignificantly higher than the oral group. Overall, serum titer showed a rapid response with spiked significant response by 48h pi in the gum vaccine groups (especially GVOR), which peaks by day 3 and remains insignificantly higher throughout the day 7 pi compared to vaccine alone groups. In conclusion, use of the mucilage from C. odorata and K. senegalenses in equal proportion has given better enhancement of the response to IBDV vaccination and premise for further investigations for improvement against IBD.

Clinicopathological evaluation of Newcastle disease virus vaccination using gums from Cedrela odorata and Khaya senegalensis as delivery agents in challenged chickens

Following previous studies on delivery potential and immune response of chickens given Newcastle disease vaccine with gums, this study was conducted to evaluate the protective ability of vaccines delivered with plant gums against clinicopathological features of Newcastle disease (ND). Processed gums from incised trunks of Cedrela odorata and Khaya senegalensis trees were combined with ND vaccine in ratio 2:2:1 and administered at 21 days to white leghorn cockerels after weaning of maternal antibodies. The birds were grouped into gum-vaccine-oral (GVOR), vaccine-oral (VOR), gum-vaccine-ocular (GVOC), vaccine-ocular (VOC), gum-oral (GOR), gum-ocular (GOC), no-gum-no-vaccine/challenged (NGNV/C), no-gum-no-vaccine/unchallenged (NGNV/U). Vaccination was boosted with the same preparation at day 42 while birds were challenged with live ND virus (KUDU strain) at day 84. Clinical signs (Dullness, Diarrhoea, Paralysis, Torticollis) Post infection (Pi), terminal weakness, gross and histology lesions were scored on a severity scale from absent (0-), mild (1+) to moderate (2+) and severe (3+). Scores were assigned a quantitative score of 0, 10, 20, 30 respectively. Clinical signs scores for the 5 week Pi were subjected to Friedman test to assess the significance of severity among the groups. The test was significant at 1% significance level which implies that the clinical signs ranked highest in the NGNV/C, followed by the Gum alone groups, the vaccine alone groups and the gum-vaccine groups irrespective of route. Moribund birds subsequently euthanized were seen in the GOR and GOC group at 21% each and at 57% in NGNV/C group alone. No signs were seen in the NVNG/U group. Grossly, mild to moderate lesions were seen in all groups except GVOR and NGNV/U. At histology, pulmonary congestion, acute pneumonia, cecal tonsilar haemorrhages, gliosis and neuronophagia were present at different proportions in all groups except the GVOR and NGNV/U. Overall, lesion severity was least in the gum-vaccine groups while the oral groups had less lesion score compared to the ocular. From this study, phytogenic mucoadhesives polymers used hold immense potential as a delivery agent capable of improving protection against clinicopathologic features of Newcastle disease in previously vaccinated birds.

Adjuvants for Clostridium tetani and Clostridium diphtheriae vaccines updating

It's known that diphtheria and tetanus are a contagious lethal diseases over the years, they caused by pathogenic microbes corynebacterium diphtheria and Clostridium tetani, respectively. The diseases result from the production of bacterial toxin. Vaccination with bacterial toxoid vaccines adsorbed on particulates adjuvants still are the best way to prevent this epidemic diseases from spread. The particulate vaccines have been shown to be more efficient than soluble one for the induction of the immune responses. Nanoparticles can be engineered to enhance the immune responses. As well known the immune response to inactivate killed and subunit vaccine enhances by alum adjuvants. The adjuvants examined and tested after reducing its size to particle size, thus mimic size of viruses which is considered smallest units can derive the immune system. The major issue is minimizing the adjuvant particles, to gain insight of resulting immunity types and impact on immune response. The adjuvant effect of micro/nanoparticles appears to largely be a consequence of their uptake into antigen presenting cells.

Evaluation of immune response in challenged chickens vaccinated with Newcastle disease vaccine using gums from Cedrela odorata and Khaya senegalensis as delivery agents

Immune response of challenged chickens following previous vaccinations with Newcastle disease vaccine using gums from Cedrela odorata and Khaya senegalensis as delivery agent were evaluated. Two hundred and fifty-two one-day old chickens were divided into vaccine-gum oral (GVOR), vaccine-gum ocular (GVOC), vaccine oral (VOR), vaccine ocular (VOC), gum oral (GOR), gum ocular (GOC), No-gum-no-vaccine/challenged (NGNV/C), and No-gum-no-vaccine/unchallenged (NGNV/U) groups. They were vaccinated at days 21 & 42 and challenged at day 84. Trachea and intestinal washings were collected at intervals as well as weekly serum samples. These were analyzed using enzyme-linked immunosorbent assay (ELISA) and haemagglutination inhibition (HI) test for mucosal and systemic IgG response (MA and SA). Statistical analysis was done using Omnibus one-way ANOVA. MA and SA were not different (P > 0.05) post first and second vaccination although gum-vaccine groups were marginally higher post second vaccination. Post Infection (PI), there was an early and sustained spike in both MA and SA for the GV groups especially GVOR (P < 0.05). MA and SA for the Gum alone (especially GOR) groups also spiked PI (P < 0.05). Therefore, phytogenic polymers used could be said to possess immunopotentiating property with a possible induction of immunologic memory mechanism.