Insufficient experimental studies have reported the effect of ovalbumin (OVA) as an allergen towards embryonic growth in asthma mouse model. The impact of 10 μg/200 μL OVA on maternal inflammatory and oxidative stress (OS) responses, and preimplantation embryonic development was investigated in this study. We first established OVA-induced asthma mouse model, and following superovulation, mated the females and challenged them with Methacholine (Mch) test. Upon embryo retrieval, only those with the highest implantation potential were cultured in vitro. Significant reduction in the number of embryos at each preimplantation stage was noted in the treated group. Uneven sized blastomeres at 2-, 4- and 8-cell stages were also evident in this group. Embryo fragmentation was significant at only 2-, 4- and 8-cell stages. We also found that OVA tended to raise maternal inflammatory and OS biomarker levels as well as to cause inappropriate levels of pregnancy hormones progesterone (P4) and estrogen (E2) although insignificant. The combined results indicate that 10 μg/200 μL OVA had altered both quality and quantity of the embryos in asthma mouse model although its effect on pregnancy hormones, inflammatory and OS responses were non-pathological.
The current conventional injectable vaccines face several drawbacks such as inconvenience and ineffectiveness in mucosal immunization. Therefore, the current development of effective oral vaccines is vital to enable the generation of dual systemic and mucosal immunity. In the present study, we examine the potential of pH-responsive bacterial nanocellulose/polyacrylic acid (BNC/PAA) hydrogel microparticles (MPs) as an oral vaccine carrier. In-vitro entrapment efficiency and release study of Ovalbumin (Ova) demonstrated that as high as 72% of Ova were entrapped in the hydrogel, and the release of loaded Ova was pH-dependent. The released Ova remained structurally conserved as evident by Western blot and circular dichroism. Hydrogel MPs reduced the TEER measurement of HT29MTX/Caco2/Raji B triple co-culture monolayer by reversibly opening the tight junctions (TJs) as shown in the TEM images. The ligated ileal loop assay revealed that hydrogel MPs could facilitate the penetration of FITC-Ova into the Peyer's patches in small intestine. Ova and cholera toxin B (CTB) were utilized in in-vivo oral immunization as model antigen and mucosal adjuvant. The in-vivo immunization revealed mice orally administered with Ova and CTB-loaded hydrogel MPs generated significantly higher level of serum anti-Ova IgG and mucosal anti-Ova IgA in the intestinal washes, compared to intramuscular administrated Ova. These results conclude that BNC/PAA hydrogel MPs is a potential oral vaccine carrier for effective oral immunization.
An experiment was conducted with the objective to enhance mucosal immunity against ovalbumin (OVA) by co-administration of OVA with an aqueous extract from the fruit of Solanum torvum (STE). Five groups of female ICR mice aged approximately 8 weeks at the commencement of the experiment were caged in groups of eight and received various treatments. The treatments included OVA alone, OVA with cholera toxin (CT), and OVA with various doses of STE. Mice were primed intraperitoneally with 500 microg of OVA alone or co-administered with 0.1 microg CT, or with 1 microg STE. All mice were boosted orally via gastric intubation 14 days after priming with 10 mg OVA alone, or co-administered with 10 microg CT or with 10 mg, 1 mg or 0.1 mg STE. One week later all mice were killed and organs obtained for analysis of the immune response. Intestinal, faecal and pulmonary OVA-specific sIgA concentration was significantly increased (p<0.05) in mice that received booster combinations of OVA/CT and OVA with all extract doses (p<0.05). Specific serum IgG titres did not differ significantly between groups. It is concluded that STE can significantly enhance secretory immunity in the intestine to OVA with mucosal homing to the lungs. The adjuvant effect of STE is comparable to that of CT.