Simple extraction of Campylobacter lipopolysaccharide and protein antigens and production of their antibodies in egg yolk

Liposomal-lipopolysaccharide vaccine extracted from Proteus mirabilis induces moderate TLR4 and CD14 production

Proteus mirabilis is a common cause of recurrent urinary tract infections in individuals with functional or structural abnormalities. It also forms bladder and kidney stones. Lipopolysaccharide (LPS) is a potential Proteus virulence factor that plays a key role in pathogenesis, as well as in stimulating innate immune response. Therefore, this study aimed to extract LPS from a highly resistant isolate and incorporate it in a delivery system (liposome) to stimulate an immune response against virulent pathogens. In the work, 50 isolates of P. mirabilis were taken from 200 urine specimens obtained from recurrent-urinary tract infections (UTI) of patients of AL-Sadar Hospital. Specimens were cultured on specific media, and then bacterial isolates were identified via morphological, biochemical and Vitek-2 systems. The results showed that P. mirabilis was expressed in 11 (22%), 30 (60%) and 9 (18%) recurrent UTI, kidney stone and catheter samples, respectively. All isolates were assessed through antibiogram testing, with the results revealing that most isolates were multidrug resistant to more than 3 classes of antibiotics. Herein, P. mirabilis NO 50 revealed particularly high resistance, so it was chosen for LPS extraction. Lethal dose 50 (LD50) observations indicated that a live suspension of P. mirabilis was at 4.5×107 CFU/ml, while LPS was at 270 μg/ml. LPS was used as an immunogenic to stimulate the immune system through injecting Rats intraperitoneally (I.P.) with 1 ml of LD50%. Subsequently, the efficiency of immunogenes in stimulating the immune response was evaluated by determining the Toll-like receptor and CD14 levels. The results indicate that LPS incorporated in the Liposome released moderate levels of Toll-like receptors-4 (TLR4) that enabled the immune system to clear pathogens. The LPS+ complete Freund’s adjuvant (CFA) and LPS vaccinated groups recorded hyper production for TLR4 (52.2 and 40.9 pg/ml, respectively), this was followed by liposome (LIP) and bacterial suspension (11 and 20.5 pg/ml, respectively) in ranking effectiveness. This study reveals a mean of CD14 that was higher in both LPS and LPS+CFA and moderate in LPS+LIP, in comparison with control and liposome groups.

In conclusion, LPS-Liposomes are a promising nanomedicine for modulating the hyper response of LPS. This may lead to tissue inflammation but appeared beneficial in stimulating the immune response at moderate levels so as to eradicate infection without tissue damage.

Human haemoclassification by use of specific yolk antibodies obtained after immunisation of chickens against human blood group antigens

Polyclonal antibodies, widely used in research and diagnostics, are conventionally isolated from the blood of immunised mammals, especially rabbits. The fact that antibodies can also be detected in the yolk of eggs laid by immunised hens, led to the development of yolk antibody technology (IgY-technology) as an alternative method that is less stressful to animals. This technology has become a worthwhile alternative to the blood-dependent techniques. Furthermore, because of the phylogenetic distance between birds and mammals, avian antigens have a very specific immune response to highly conserved antigens of mammals, such as human erythrocyte antigens. To evaluate the humoral immune response of hens immunised with human red erythrocyte antigens, 22 White Leghorn hens were kept in cages and immunised with total red blood cells or stroma of the human rhesus positive (Rh+) system (D antigen) by weekly intramuscular and intravenous injections, without the use of an adjuvant. The haemagglutination assay was used to evaluate the dynamics of the production of IgY antibodies against human erythrocyte antigens, and single radial immunodiffusion was used to evaluate the amount of total IgY in de-lipidated supernatants from egg yolk. The highest titres were observed four weeks after the first immunisation, and these remained stable for up to seven weeks for the intravenous route. Positive reactivity against human erythrocyte antigens A, B and O was demonstrated in de-lipidated supernatants from the egg yolks of immunised hens. The strongest reaction was observed against blood group O Rh+ (O+).