Toxicological data of rats and rabbits: Sub-chronic testing of recombinant HPV vaccine through oral and intranasal routes.

Current article illustrates the data of body weight, biochemical, haematological profile, and organ weights of rats and rabbits administered with recombinant human papilloma virus (HPV) vaccine, along with genotoxicity effect. The data was collected from nonclinical safety/toxicity and immune response evaluations of recombinant Salmonella typhi expressing the HPV 16 and 18 L1 proteins as vaccine. The intended clinical route of vaccine administration is through oral route, whereas it is established fact that attenuated S. typhi could not colonize in laboratory animals. In view of this it is challenging to undertake the nonclinical safety/toxicity evaluations following the regulatory guidelines. Hence sub chronic safety/toxicity testing was carried out in rat and rabbits by administration of HPV vaccine through oral (intended clinical route) and innovative intranasal routes. The prophylactic dose derived from adult human clinical dose (2 × 109CFU/70 kg) was administered to SD rats (PD: 0.18 × 109CFU/kg) and New Zealand White (NZW) rabbits (PD: 0.09 × 109CFU/kg) through oral and intranasal routes. Similarly, average dose (AD:5xPD) was administered to rats (AD:0.9 × 109CFU/kg) and rabbits (AD: 0.45 × 109CFU/kg) through intranasal route only. The repeated doses were administered on 3rd and 5th days of post-exposure of 1st dose through specified routes and test compound effects in relation with time of exposure was assessed by euthanizing animals and data collection at different time points i.e. 15th (25% of animals), 29th (25% of animals) and 93rd days (50% of animals) of post-exposure of 1st dose. The retro-orbital plexus blood was collected before euthanizing animals to unveil the biochemical and haematological profile. The data on genotoxicity effect of test compound, if any, was obtained by assessing the bone-marrow micronucleus assay. The immune response and allergenicity in terms of specific IgG and IgE levels against HPV 16 and 18 L1 proteins were determined in mice. The raw data of various parameters collected at different time points were compiled and computed according to the groups. The haematological profile and organ weights data can be used as reference data for SD rats and NZW rabbits for future studies.

Nonclinical safety evaluation of oral recombinant anti-human papilloma virus vaccine (RHPV 16 & 18): Regulatory toxicology studies in mice, rats and rabbits - An innovative approach.

AIM: The human papilloma virus (HPV) type 16 and 18 causes nearly 70% of uterine cervical cancers. Oral administration of live Salmonella typhi Ty21a, expressing major capsid proteins (L1) of HPV 16 and 18 is a potential choice for immunization in adolescent girls under low resource settings. Present study aimed to assess the nonclinical safety of recombinant S. typhi expressing HPV 16 and 18 (rStHPV) proteins. METHODOLOGY: The acute toxicity of rStHPV was tested by intranasal single dose administration, of 10 and 50 folds higher than clinical prophylactic dose, in mice and rat followed by monitoring their survival for 14 days. Sub-chronic toxicity was evaluated in rats and rabbits with prophylactic and 5 times (average) to clinical prophylactic dosages on scheduled days (1st, 3rd & 5th day) through oral and intranasal routes. The immune/allergic response of rStHPV was assessed in mice through intranasal and intra-peritoneal routes. Experimental animals were daily monitored for live phase, and clinical chemistry, haematology, immunotoxicology, immunogenic response and histopathological examination of vital organs on 15th, 29th and 93rd days. RESULTS: No abnormal changes were noticed in live phase activity, clinical chemistry and haematology profile. The gross necropsy, organ weights and histopathology were found to be normal. No immunotoxicity was recorded as evaluated by tier I tests. Allergic immune response, as evaluated with IgE levels was also negative irrespective of test routes. On the other hand, a significant (P < 0.01) increase of anti-HPV IgG levels was noted in mice exposed through intranasal route. Though the pre-terminal mortality was noted in mice (6-15%), rats (10%) and rabbits (15%), the autopsy revealed no signs of toxicity related to rStHPV, as the changes neither significant nor dose dependent; and even noted in vehicle control also. CONCLUSION: The study results suggested 'no observable adverse effects' of rStHPV even at higher dosages (5, 10 & 50 folds) than intended clinical dose. A significant increase of anti-HPV specific IgG suggests the immunogenicity of vaccine. The innovative approach of current study is nonclinical toxicology evaluation of vaccine through intra-nasal route, an alternate route apart from stipulated regulatory guidelines.

Interleukin-18-induced cell adhesion molecule expression is associated with feedback regulation by PPAR-γ and NF-κB in Apo E-/- mice.

Focal recruitment of monocytes and lymphocytes is one of the earliest detectable cellular responses in atherosclerotic lesion formation. Endothelium may regulate leukocyte recruitment by expressing specific adhesion molecules. Interleukin-18 is a proinflammatory cytokine that plays an important role in vascular pathologies. The present study highlights the modulation of adhesion molecules and PPAR-γ by IL-18 and proposes a novel feedback mechanism by which PPAR-γ may regulate IL-18 expression. Three groups of normal chow diet-fed, male Apo E-/- mice, aged 12 weeks (n = 6/group) were employed: Gp I, phosphate-buffered saline (PBS) (2 mo): Gp II, recombinant IL-18 (rIL-18) (1 mo) followed by PBS (1 mo); Gp III, rIL-18 (1 mo) followed by pyrrolidine dithiocarbamate (PDTC) (1 mo). Significantly augmented mRNA expression of ICAM-1 (~5.7-fold), VCAM-1 (~3.6-fold), and NF-κB (~7-fold) was observed in Gp II mice as compared to Gp I, whereas PPAR-γ expression was not altered. PDTC treatment caused a significant downregulation of ICAM-1 (~4.2-fold), VCAM-1(~2-fold), and NF-κB (~4.5-fold) and upregulation of PPAR-γ expression (~5-fold) in Gp III mice. A similar trend was observed in protein expression. In vivo imaging results demonstrated a marked increase in probe (CF750 dye conjugated to VCAM-1 antibody) fluorescence intensity for VCAM-1 expression in Gp II mice, whereas it was moderately decreased in Gp III. PPAR-γ was found to significantly downregulate both IL-18 levels and IL-18-induced adhesion molecules. The underlying mechanism was found to be via inhibition of NF-κB activity by PDTC, thereby leading to decreased adherence of monocytes to the activated endothelial cells and a step to halt the progression and development of atherosclerotic lesions.

Combination of spices and herbal extract restores macrophage foam cell migration and abrogates the athero-inflammatory signalling cascade of atherogenesis.

The trapping of lipid-laden macrophages in the arterial intima is a critical but reversible step in atherogenesis. However, information about possible treatments for this condition is lacking. Here, we hypothesized that combining the polyphenol-rich fractions (PHC) of commonly consumed spices (Allium sativum L (Liliaceae), Zingiber officinale R (Zingiberaceae), Curcuma longa L (Zingiberaceae)) and herbs (Terminalia arjuna (R) W & A (Combretaceae) and Cyperus rotundus L (Cyperaceae)) prevents foam cell formation and atherogenesis. Using an in vitro foam cell formation assay, we found that PHC significantly inhibited lipid-laden macrophage foam cell formation compared to the depleted polyphenol fraction of PHC (F-PHC). We further observed that PHC attenuated the LDL and LPS induced CD36, p-FAK and PPAR-γ protein expression in macrophages and increased their migration. NK-κB-DNA interaction, TNF-α, ROS generation, and MMP9 and MMP2 protein expression were suppressed in PHC-treated macrophages. The anti-atherosclerotic activity of PHC was investigated in a high fat- and cholesterol-fed rabbit model. The inhibition of foam cell deposition within the aortic intima and atheroma formation confirmed the atheroprotective activity of PHC. Therefore, we conclude that the armoury of polyphenols in PHC attenuates the CD36 signalling cascade-mediated foam cell formation, enhances the migration of these cells and prevents atherogenesis.

Lead and essential trace element levels in school children: a cross-sectional study.

BACKGROUND: Nutritional status is thought to modulate susceptibility to lead (Pb) toxicity. The type and nature of these interactions needs to be investigated. AIM: To assess the prevalence of sub-clinical Pb toxicity (defined by ≥ 10 µ_rm;g/dL blood levels) and trace element deficiencies (Iron (Fe), Zinc (Zn), Copper (Cu) and Magnesium (Mg)) and to find out their possible relationship, if any. SUBJECTS AND METHODS: A cross-sectional survey was carried out in a total of 195 school children residing in urban (n = 65), urban heavy traffic (n = 65) and urban industrial (n = 65) zones of Hyderabad, India. Blood Pb, trace element levels, haemoglobin and δ-aminolevulinate dehydratase (δ-ALAD) activity was measured. RESULTS: High blood lead levels ( ≥ 10 µ_rm;g/dL) were observed in 54.3% of children while percentage prevalence of trace element deficiencies such as Fe (16.2%), Zn (68.6%), Mg (41.7%) and Cu (25%) were also high in children included in the study. Higher blood Pb levels and reduced δ-ALAD activity was observed in children residing in heavy traffic and industrial areas. Blood Pb levels but not δ-ALAD activity correlated inversely with serum Fe in heavy traffic and industrial children, respectively. Interestingly, δ-ALAD activity but not blood Pb levels correlated inversely with trace element levels only in urban children. CONCLUSIONS: These results suggest higher prevalence of sub-clinical Pb toxicity and trace element deficiencies in urban children. Further, high blood Pb levels appear to be correlated with reduced δ-ALAD activity and iron status in Pb exposed children.