Infected Rabbits Research Articles

Preliminary evaluation of the protective effect of rEi-SAG19 on Eimeria intestinalis infection in rabbits

Eimeria intestinalis is one of the most pathogenic coccidia species in rabbits. Anticoccidial treaments are the main measures to control rabbit coccidiosis now, but there are drug resistance and residues concerns. Therefore, vaccine has been used as an alternative strategy. The surface antigens (SAGs) of apicomplexan protozoa play a role in adhesion and invasion of host intestinal cells, and are considered to be potential candidate antigens for vaccines. In this study, transcriptional analysis of 5 Ei-SAGs genes at four developmental stages was conducted, then the Ei-SAG19 gene were screened out for prokaryotic expression and the reactogenicity of recombinant SAG19 (rEi-SAG19) was investigated by immunoblotting. To assessment the protective effects of rEi-SAG19, rabbits (n = 40) were randomly divided into four groups (Blank control, PBS-infected, Trx-His-S-Quil-A-infected and rEi-SAG19 immunized groups), the rEi-SAG19 immunized group was subcutaneously immunized with 100 μg rEi-SAG19 in the neck with an interval of two weeks, and challenged with 5 × 104 homologous oocysts two weeks after the second immunization. Two weeks after the challenge, all rabbits were sacrificed. After that, the level of serum specific IgG antibody was detected weekly and the level of cytokines in serum before the challenge were determined. At the end of the experiment, the weight gain, oocyst reduction rate, lesion score and anticoccidial index (ACI) were calculated. The results showed that rEi-SAG19 has a good reactogenicity. The relative weight gain rate, oocyst reduction rate and ACI of the rabbits in rEi-SAG19 immunized group were 80.51%, 72.6%, and 165.1, respectively, which has a moderate protective effect. The level of serum specific IgG antibody and IL-4 rised significantly (P < 0.05), but the levels of IL-2, IFN-γ and IL-10 had no significant difference (P > 0.05). Our results indicated that rEi-SAG19 could provides moderate protective effect against E. intestinalis infection in rabbits (ACI = 165.1). Therefore, rEi-SAG19 could be used as a vaccine candidate antigen for E. intestinalis.

Association of Encephalitozoon cuniculi with Clinical Signs and Abnormal Hematologic/Biochemical Changes in Pet Rabbits in Thailand.

Encephalitozoon cuniculi can cause serious disease and subclinical infection in rabbits and requires active surveillance to control the infection. This study investigated the association between anti-Encephalitozoon cuniculi antibody status and various health parameters in pet rabbits. A total of 90 rabbits were divided into healthy (N = 30), subclinical (N = 30), and clinical (N = 30) groups based on their anti-Encephalitozoon cuniculi antibody status and clinical presentations. The mean ages of the control (37 ± 40 months) and subclinical groups (38 ± 34 months) were notably lower compared to that of the clinical group (63 ± 38 months, p < 0.01). Serum titers for anti-Encephalitozoon cuniculi antibodies were significantly elevated in rabbits with subclinical and clinical infections compared to those of healthy rabbits (p < 0.05). Neurological signs were predominant in rabbits with active E. cuniculi infection (80.0%), with additional pathological features including urinary dysfunction (10.0%) and cataracts (10.0%). The source of rabbits was not associated with E. cuniculi infection (p = 0.159). Anemia was significantly linked to E. cuniculi infection (p = 0.026); however, no significant associations were found with leukocytosis, thrombocytopenia, or serum biochemistry parameters. Mature adult rabbits were more likely to be infected with E. cuniculi. Recognizing anemia and neurological signs facilitates in early diagnosis of E. cuniculi infection.

Inter and Intraserotype Variations of Streptococcus Pneumoniae Pathogenicity in Mice and Rabbits

The small mammalian labratory animals, the mice and the rabbits were tempted to be pathogenicity models for S. pneumoniae serotypes 1 and 6, the infecting doses were 0.3ml for mice and 0.5 ml for rabbits. These infectious doses were rated to a count of 1X 10 to 7 CFU/ml. The infection routes were intrapreritoneal for mice and intranasal for rabbits. The gold standard criteria for pathogenicity were the death end point DEP.DEP was up to 24hr for mice and ranged from four to 14 days in rabbits. Mice was more susciptable than rabbits for S. pneumoniae serotypes infections. Autopsy cultures of blood, lungs, liver and kideys were producing same infecting serotype both from mice and rabbits. This isolation profile was indicating bacterimic state induced by infection. Different serotypes have shown different death end points duration time. There were inter and intraserotype variations in DEP. Moderate to severe respiratory disease conditions RDC was noted in mice while mild RDC in rabbits. Both of the tested models were similar lung histology to man. The histological features of this experimental infections have shown that the infected mice and rabbits were of bronchopneumonia type. It appears that both mice and rabbits were standing as valid laboratory animal models for these local clinical isolates of S. pneumoniae serotypes.

Intravitreal chlorhexidine for sterilizing the vitreous cavity in an animal model of bacterial endophthalmitis

Purpose To evaluate the efficacy and safety of intravitreal chlorhexidine (CHX) for sterilising the vitreous cavity in bacterial endophthalmitis. Methods For in-vitro experiments, full-thickness retina explants were harvested from freshly enucleated pig eyes. Six-millimeter circular sensory retina patches were then incubated in varying concentrations of CHX (0.625-800 µg/mL) for 24 hours. Retinal cell viability was determined at the end of the incubation period with a live-dead assay. The bactericidal effects of the tested CHX concentrations were determined using a quantitative suspension test on Staphylococcus epidermidis. The safety of CHX was also tested by injecting varying doses of CHX (50-400 µg/mL) into the vitreous cavity of albino rabbits followed by flash electroretinography (ERG) and light microscopy. The bactericidal effect of the non-toxic CHX doses was determined using the rabbit model of endophthalmitis created by injecting 3000 CFU/0.1 mL of Staphylococcus epidermidis. Results In vitro concentrations of CHX greater than 6.25 µgr/mL exerted a bactericidal effect, while concentrations of CHX less than 200 µg/mL did not impair retinal cell viability. Intravitreal concentrations of CHX between 20-100 µg/mL were adequate to sterilise the infected rabbit vitreous cavity in the animal model. No significant functional or anatomical deleterious effect was observed with ERG or light microscopy. Conclusion CHX can sterilise the vitreous cavity in an animal model of bacterial endophthalmitis without impairing retinal cell viability. Our results encourage further research for clinical use of chlorhexidine in treatment of bacterial endophthalmitis.

MicroRNAs Regulate the Expression of Genes Related to the Innate Immune and Inflammatory Response in Rabbits Infected with Lagovirus europaeus GI.1 and GI.2 Genotypes.

MicroRNAs (miR) are a group of small, non-coding RNAs of 17-25 nucleotides that regulate gene expression at the post-transcriptional level. Dysregulation of miRNA expression or function may contribute to abnormal gene expression and signaling pathways, leading to disease pathology. Lagovirus europaeus (L. europaeus) causes severe disease in rabbits called rabbit hemorrhagic disease (RHD). The symptoms of liver, lung, kidney, and spleen degeneration observed during RHD are similar to those of acute liver failure (ALF) and multi-organ failure (MOF) in humans. In this study, we assessed the expression of miRs and their target genes involved in the innate immune and inflammatory response. Also, we assessed their potential impact on pathways in L. europaeus infection-two genotypes (GI.1 and GI.2)-in the liver, lungs, kidneys, and spleen. The expression of miRs and target genes was determined using quantitative real-time PCR (qPCR). We assessed the expression of miR-155 (MyD88, TAB2, p65, NLRP3), miR-146a (IRAK1, TRAF6), miR-223 (TLR4, IKKα, NLRP3), and miR-125b (MyD88). We also examined biomarkers of inflammation: IL-1β, IL-6, TNF-α, and IL-18 in four tissues at the mRNA level. Our study shows that the main regulators of the innate immune and inflammatory response in L. europaeus/GI.1 and GI.2 infection, as well as RHD, are miR-155, miR-223, and miR-146a. During infection with L. europaeus/RHD, miR-155 has both pro- and anti-inflammatory effects in the liver and anti-inflammatory effects in the kidneys and spleen; miR-146a has anti-inflammatory effects in the liver, lungs and kidneys; miR-223 has anti-inflammatory effects in all tissues; however, miR-125b has anti-inflammatory effects only in the liver. In each case, such an effect may be a determinant of the pathogenesis of RHD. Our research shows that miRs may regulate three innate immune and inflammatory response pathways in L. europaeus infection. However, the result of this regulation may be influenced by the tissue microenvironment. Our research shows that infection of rabbits with L. europaeus/GI.1 and GI.2 genotypes causes an overexpression of two critical acute phase cytokines: IL-6 in all examined tissues and TNF-α (in the liver, lungs, and spleen). IL-1β was highly expressed only in the lungs after L. europaeus infection. These facts indicate a strong and rapid involvement of the local innate immune and inflammatory response in L. europaeus infection-two genotypes (GI.1 and GI.2)-and in the pathogenesis of RHD. Profile of biomarkers of inflammation in rabbits infected with L. europaeus/GI.1 and GI.2 genotypes are similar regarding the nature of changes but are different for individual tissues. Therefore, we propose three inflammation profiles for L. europaeus infection for both GI.1 and GI.2 genotypes (pulmonary, renal, liver, and spleen).

Epidemiologic, clinicopathologic, and diagnostic findings in pet rabbits with myxomatosis caused by the California MSW strain of myxoma virus: 11 cases (2022-2023).

To determine epidemiologic features of naturally occurring myxomatosis in domestic rabbits in California and to characterize clinicopathologic and diagnostic findings. 11 client-owned rabbits, Oryctolagus cuniculus subsp domesticus. A prospective study of pet rabbits with myxomatosis seen at an exotic animal specialty clinic in Santa Cruz county, California, was conducted between January 1, 2022, and December 31, 2023. Rabbits were included in the study if they had bilateral blepharedema and were PCR positive for myxoma virus. All infected rabbits had spent time outdoors. Common clinical signs included bilateral blepharedema (11/11), anogenital edema (10/11), rectal temperature ≥ 39.7 °C (5/9), and sudden death (4/11). Eyelid biopsies from all rabbits (11/11) were positive for myxoma virus by qualitative PCR followed by Sanger sequencing (100% nucleotide identity to strain MSW, also known as California/San Francisco 1950 [Genbank accession KF148065]). Most rabbits had keratinocytes containing eosinophilic intracytoplasmic viral inclusions in biopsies of edematous skin (8/11) and lymphocyte necrosis in the spleen (10/11). Immunohistochemistry identified myxoma virus in samples of skin, heart, lung, ileum, spleen, and lymph node. Clinical signs of myxomatosis caused by the MSW strain of myxoma virus are distinctive but subtle. Cases occur regularly in the Santa Cruz and San Jose regions of California. As infection with this virus is almost 100% fatal and no vaccine is available in the US, owners of domestic rabbits in endemic areas should keep their pets indoors or behind mosquito screens. Myxomatosis is a reportable disease in the US, and the appropriate state or federal agencies should be contacted when outbreaks occur.

Vancomycin-encapsulated hydrogel loaded microarc-oxidized 3D-printed porous Ti6Al4V implant for infected bone defects: Reconstruction, anti-infection, and osseointegration

Infected bone defect is a formidable clinical challenge. Conventional approaches to prevention and treatment for infected bone defects are unsatisfactory. The key elements of the treatment are bone defect reconstruction, anti-infection, and osteogenesis. Conventional treatment methods remain unsatisfactory owing to the absence of composite integrating materials with anti-infective, and osteogenic activities as well as proper mechanical strength at the same time. In this study, we fabricated a vancomycin-encapsulated hydrogel with bacteria-responsive release properties combined with a shaved porous (submicron-micron) three-dimensional-printed Ti6Al4V implant. The implant surface, modified with submicron-sized pores through microarc oxidation (MAO), showed enhanced osteogenic activity and integrated well with the hydrogel drug release system, enabling sustained vancomycin release. In vitro experiments underscored the commendable antibacterial ability, biosafety, and osteoinductive potential. Effective antibacterial and osteogenic abilities of the implant were further demonstrated in vivo in infected rabbit bone defects. These results showed that the vancomycin-encapsulated hydrogel-loaded microarc-oxidized 3D-printed porous Ti6Al4V can repair the infected bone defects with satisfactory anti-infection and osseointegration effects.

A Case Study on Sarcocystis in Laboratory Rabbit

Sarcocystosis spp. was diagnosed in Newzealand white rabbit which was brought for the purpose of experiment. The rabbit was brought from the local market and rearing in group in cage and feed locally available grasses. No any clinical signs were observed infected rabbit. The physiological along with biochemical and hematological test were performed. At necropsy and tissue harvest, a gross lesion was not observed in heart. During histo-pathological observation, an oval round shape along with longitudinal shape cyst was observed in the myocardium.

The Different Influence of Cutibacterium acnes and Staphylococcus epidermidis in the Lumbar Disc : An in Vivo Study in Rabbits.

Animal laboratory study. This study investigated the effects of Cutibacteriumacnes and Staphylococcusepidermidis on the lumbar discs of rabbits, as well as the outcomes of combined infection. Many studies have indicated that bacterial infections are associated with lumbar disc degeneration (LDD). The most commonly cultured bacteria from disc tissues are C. acnes and S. epidermidis . New Zealand white rabbits (n=40) were randomly divided into control, C. acnes , S. epidermidis , and C. acnes plus S. epidermidis ( i.e. , combined) groups. All groups except the control were injected with 25μL of saline at L4-L5 and 25μL of bacteria (1×10 7 CFU/mL) at L5-L6. All injections were performed under x-ray guidance. Weight measurements, haematological evaluations, and magnetic resonance imaging were performed after 4, 8, and 12 weeks. Histological examination and gene expression detection were performed 12 weeks after surgery. Inflammatory factors in the blood and weight did not differ among the groups after 4, 8, and 12 weeks ( P >0.05). However, after 4 weeks, LDD occurred in the C. acnes group, and discitis occurred in the S. epidermidis and combined groups, all of which worsened after 8 weeks. After 12 weeks, the nucleus pulposus (NP) protruded and compressed the spinal cord in the C. acnes group, and tissue staining showed decreased NP tissue and cartilaginous endplate fracture. In the S. epidermidis and combined groups, the discitis was more confined, but tissue staining revealed a significant decrease in NP tissue, and loss of the normal disc structure. In the early stage of infection in rabbits, C. acnes caused LDD, and S. epidermidis caused discitis. Coinfection with C. acnes and S. epidermidis caused discitis but was more limited in scope than infection with S. epidermidis alone.

Haematobiochemical Alterations in Rabbit Mange

Mange in rabbits is an economically important parasitic disease which cause significant loss in productivity, body weight and fur quality. Forty eight rabbits with clinical signs of alopecia, anorexia, pruritis, skin erosions and dry crust like lesions on extremities, ears, nose and face were brought to Veterinary Clinical Complex, Rajendranagar and Hyderabad. Skin scrapings were collected, processed and examined under microscope to detect mite infestation. Different mites i.e. Sarcoptes scabiei, Psoroptes cuniculi, Notoedres cuniculi, Demodex cuniculi and Cheyletiella parasitivorax were noticed in rabbits. Haematological examination revealed a significant (p&lt;0.05) decrease in haemoglobin, PCV, RBC count and a significant (p&lt;0.05) increase in TLC count in affected rabbits. Serum analysis showed a significant (p&lt;0.05) increase in ALT and AST levels in infected rabbits. Treatment with ivermectin along with proper management resulted in recovery from mange in rabbits.

Infection of Egyptian domestic rabbits, Oryctolagus cuniculus, with Cysticercus pisiformis (Cestoda: Taeniidae): morphological, molecular, and histopathological diagnostic tools.

Cysticercosis raises the alarm for domestic rabbits since it has a significant impact on their health, productivity, and nutritional value. In this study, several white creamy- colored cysts were detected in the mesentery of the stomach and intestine, as well as embedded in the liver of domestic rabbits collected from Qena Governorate, Egypt. Based on both morphological and molecular assessments, revealed cysts could be identified as Cysticercus pisiformis, the larval stage of Taenia pisiformis. Gross and histopathological investigations of infected organs were documented. To our knowledge, this is the first geographical report on Cysticercus pisiformis in domestic rabbits in Qena Governorate, using current morphological, molecular, and histopathological methodologies that provide critical data for developing diagnostic targets for C. pisiformis.

Optimization of immunosuppression strategies for the establishment of chronic hepatitis E virus infection in rabbits.

Chronic hepatitis E mostly occurs in organ transplant recipients and can lead to rapid liver fibrosis and cirrhosis. Previous studies found that the development of chronic hepatitis E virus (HEV) infection is linked to the type of immunosuppressant used. Animal models are crucial for the study of pathogenesis of chronic hepatitis E. We previously established a stable chronic HEV infection rabbit model using cyclosporine A (CsA), a calcineurin inhibitor (CNI)-based immunosuppressant. However, the immunosuppression strategy and timing may be optimized, and how different types of immunosuppressants affect the establishment of chronic HEV infection in this model is still unknown. Here, we showed that chronic HEV infection can be established in 100% of rabbits when CsA treatment was started at HEV challenge or even 4 weeks after. Tacrolimus or prednisolone treatment alone also contributed to chronic HEV infection, resulting in 100% and 77.8% chronicity rates, respectively, while mycophenolate mofetil (MMF) only led to a 28.6% chronicity rate. Chronic HEV infection was accompanied with a persistent activation of innate immune response evidenced by transcriptome analysis. The suppressed adaptive immune response evidenced by low expression of genes related to cytotoxicity (like perforin and FasL) and low anti-HEV seroconversion rates may play important roles in causing chronic HEV infection. By analyzing HEV antigen concentrations with different infection outcomes, we also found that HEV antigen levels could indicate chronic HEV infection development. This study optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits and highlighted the potential association between the development of chronic HEV infection and immunosuppressants.IMPORTANCEOrgan transplant recipients are at high risk of chronic hepatitis E and generally receive a CNI-based immunosuppression regimen containing CNI (tacrolimus or CsA), MMF, and/or corticosteroids. Previously, we established stable chronic HEV infection in a rabbit model by using CsA before HEV challenge. In this study, we further optimized the immunosuppression strategies for establishing chronic HEV infection in rabbits. Chronic HEV infection can also be established when CsA treatment was started at the same time or even 4 weeks after HEV challenge, clearly indicating the risk of progression to chronic infection under these circumstances and the necessity of HEV screening for both the recipient and the donor preoperatively. CsA, tacrolimus, or prednisolone instead of MMF significantly contributed to chronic HEV infection. HEV antigen in acute infection phase indicates the development of chronic infection. Our results have important implications for understanding the potential association between chronic HEV infection and immunosuppressants.

Effects Vitis vinifera Leaves on the Oxidative Status of New Zealand Rabbit Liver Infected with Eimeria stiedae

Background: Rabbits are the most important protein sources of animals for humans all over the world. Its production has increased significantly in recent years and it has become one of the most important animal sources in the Kingdom of Saudi Arabia. Coccidiosis is one of the most dangerous diseases affecting rabbits and other animals causing global economic losses. Plant extracts have been used as potential alternatives to chemotherapy because they do not have the negative consequences of tissue deposits and drug resistance. Methods: The current study examined the antioxidant activity of Vitis vinifera leaf extract (VVLE) in New Zealand rabbits infected with Eimeria stiedae. The extract was subjected to phytochemical analysis by FT-IR. A total of 35 male New Zealand rabbits were divided into seven groups. Group 1 served as the uninfected, untreated (negative control) group. Group 2 uninfected and treated at 400 mg/kg of extract to test for toxicity. Group 3 represented the infected, non-treated (positive control) group. While, groups 4, 5 and 6 comprised infected treated with at100 mg/kg, 200 mg/kg and 400 mg/kg of extracts, respectively. Finally, group 7 consisted of infected rabbits treated with Toltrazuril at a dosage of 5 mg/kg body weight. Result: The analysis of phytochemicals by FT-IR for Vitis vinifera leaf extract revealed the existence of 15 biologically active compounds. VVLE was able to decrease the induced weight loss due to infection. Moreover, the oxidative status due to E. stiedae infection had been changed after treatment with VVLE where the level of glutathione, malondialdehyde and nitric oxide was improved indicating the antioxidant activity of the VVLE. Our findings suggested that VVLE could boost the induced oxidative stress in the liver of infected New Zealand rabbits, but studies are needed to determine the mechanism of VVLE.

In vivo and in vitro efficacy of the ithmid kohl/zinc-oxide nanoparticles, ithmid kohl/Aloe vera, and zinc-oxide nanoparticles/Aloe vera for the treatment of bacterial endophthalmitis

The aim of this study was to investigate the efficacy of the ithmid kohl/zinc-oxide nanoparticles (ZnONPs), ithmid kohl/Aloe vera, and ZnONPs/Aloe vera in the treatment of bacterial endophthalmitis. The endophthalmitis model was prepared by contaminating both eyes of 24 healthy adult male albino rabbits with a clinical isolate of Klebsiella pneumoniae. The animals were randomly divided into eight groups (A-H) according to the treatment. Group A received 1 ml of ithmid kohl/ZnONPs ointment, group B received 1 ml of ithmid kohl/Aloe vera gel ointment, group C received 1 ml of ZnONPs/Aloe vera gel ointment, and groups D, E, and F were treated with 1 ml of ithmid kohl solution (0.5 g/ml in distilled water), 1 ml of ZnONPs (0.5 g/ml) colloidal dispersion, and 1 ml of Aloe vera gel, respectively. Group G received 100 μl of a tetracycline antibiotic solution (final concentration: 16 µg/ml), and group H received sterile distilled water (no treatment). In vitro antibacterial activity was evaluated against K. pneumoniae using the agar well diffusion. The combination of ithmid kohl/ZnONPs was the most effective formulation for treating endophthalmitis model in infected rabbits within 2 days. In vitro antibacterial assay confirmed the potential of the ithmid kohl/ZnONPs formulation, which had the largest zone of inhibition (31 mm) among the compounds tested. The preparation of the ithmid kohl/ZnONPs formulation and its in vivo experiment in albino rabbits for the treatment of bacterial endophthalmitis was an innovative approach that has shown promise and may potentially serve as a viable alternative in clinical practice.

The feasibility of endoscopic autogenous fat transplantation in the treatment of gastroesophageal reflux disease: An animal pilot study

ObjectiveEndoscopic injection is one of the simplest minimally invasive methods for the treatment of gastroesophageal diseases. However, the safety of injection material limits its clinical application. We investigated the feasibility, safety and efficacy of endoscopic autogenous fat transplantation (EAFT) in the lower part of esophagus in the treatment of gastroesophageal reflux disease in New Zealand albino rabbits. MethodsEight New Zealand albino rabbits were used for autogenous fat transplantation. The dynamic pH value of the lower esophagus was monitored before and one week after fat transplantation in two rabbits. The local retention of fat was observed by endoscopy, and the pathological analysis was made at the junction of esophagus and stomach after two weeks of fat transplantation in six albino rabbits. During the experiment, the weight, dietary habit and infection of albino rabbits were monitored. ResultsEndoscopic autogenous fat transplantation of the lower esophagus was successfully performed in 8 albino rabbits. The average pH value of the esophagus increased from 5.6 to 7.5 and 7.4 to 7.9, respectively in two rabbits one week after transplantation. The fat barrier of the lower esophagus was remained locally and observed by endoscopy two weeks after transplantation in six rabbits. Pathology showed that the adipocytes survived in the submucosa with neovascularization. No complications of bleeding, perforation and infection occurred. All albino rabbits kept normal dietary habit. No significant changes in weight were observed. ConclusionEndoscopic autogenous fat transplantation in lower esophagus is considered as a safe and feasible method by preliminary animal experiments, which can provide a new option in the treatment of gastroesophageal reflux disease (GERD) and is worth further study.

Photoactivated Chromophore for Keratitis-Corneal Cross-linking (PACK-CXL)-A Scoping Review Based on Preclinical Studies.

Photoactivated chromophore for keratitis-corneal cross-linking (PACK-CXL) stabilizes the corneal stroma and eliminates microorganisms. Numerous PACK-CXL protocols, using different energy sources and chromophores, have been applied in preclinical studies, including live animal studies, with various experimental designs and endpoints. So far, a systematic mapping of the applied protocols and consistency across studies seems lacking but is essential to guide future research. The scoping review protocol was in line with the JBI Manual for Evidence Synthesis. Electronic databases were searched (Embase, MEDLINE, Scopus, Web of Science) to identify eligible records, followed by a two-step selection process (title and abstract screening, full text screening) for record inclusion. We extracted information on (1) different PACK-CXL protocol characteristics; (2) infectious pathogens tested; (3) study designs and experimental settings; and (4) endpoints used to determine antimicrobial and tissue stabilizing effects. The information was charted in frequency maps. The searches yielded 3654 unique records, 233 of which met the inclusion criteria. With 103 heterogeneous endpoints, the researchers investigated a wide range of PACK-CXL protocols. The tested microorganisms reflected pathogens commonly associated with infectious keratitis. Bacterial solutions and infectious keratitis rabbit models were the most widely used models to study the antimicrobial effects of PACK-CXL. If preclinical PACK-CXL studies are to guide future translational research, further cross-disciplinary efforts are needed to establish, promote, and facilitate acceptance of common endpoints relevant to PACK-CXL. Systematic mapping of PACK-CXL protocols in preclinical studies guides future translational research.

An injectable hydrogel based on sodium alginate and gelatin treats bacterial keratitis through multimodal antibacterial strategy

Bacterial keratitis is among the most prevalent causes of blindness. Currently, the abuse of antibiotics in clinical settings not only lacks bactericidal effects but also readily induces bacterial resistance, making the clinical treatment of bacterial keratitis a significant challenge. In this study, we present an injectable hydrogel (GS-PNH-FF@CuS/MnS) containing self-assembled diphenylalanine dipeptide (FF) and CuS/MnS nanocomposites (CuS/MnS NCs) that destroy bacterial cell walls through a synergistic combination of mild photothermal therapy (PTT), chemodynamic therapy (CDT), ion release chemotherapy, and self-assembled dipeptide contact, thereby eliminating Pseudomonas aeruginosa. Under 808 nm laser irradiation, the bactericidal efficiency of GS-PNH-FF@CuS/MnS hydrogel against P. aeruginosa in vitro reach up to 96.97 %. Furthermore, GS-PNH-FF@CuS/MnS hydrogel is applied topically to kill bacteria, reduce inflammation, and promote wound healing. Hematoxylin-eosin (H&E) staining, Masson staining, immunohistochemistry and immunofluorescence staining are used to evaluate the therapeutic effect on infected rabbit cornea models in vivo. The GS-PNH-FF@CuS/MnS demonstrate good biocompatibility with human corneal epithelial cells and exhibit no obvious eyes side effects. In conclusion, the GS-PNH-FF@CuS/MnS hydrogel in this study provides an effective and safe treatment strategy for bacterial keratitis through a multimodal approach.

Histopathological alterations caused by Klebsiella pneumoniae infection in rabbits and the preventive effects of whole sonicated killed antigen and Albizia lebbeck extract

Background. The purpose of this study is to estimate the protective capability of ethanolic Albizia lebbeck leaf extract against Klebsiella pneumoniae contagion in rabbits. Methods. The animals gathered into three groups each group contain eight albino rabbits were received the following: subcutaneously group one was received Killed Whole Cell Sonicated Antigen-Klebsiella pneumoniae (KWCSAg-KP); group two was orally received ethanolic Albizia lebbeck leaf extract and KWCSAg-KP subcutaneously; group three was quit as control group was given PBS subcutaneously. The rabbit groups were orally challenged by 1.5 × 108 CFU/ml Klebsiella pneumoniae then the rabbit were immolated ten days post-challenge for pathological changes. Spleen, liver, intestine and kidney were examined for histopathological alterations. Intestine, liver, kidney and spleen were examined for pathological changes. Results. The results revealed that the 2nd group had the least histopathological alterations with moderate infiltration of inflammatory cells in addition to no any abnormality detected in the kidney as well as the liver. The KWCSAg-KP group revealed sloughing with mild superficial inflammation in the lamina propria and mild vacuolation of the hepatocytes in the centrilobular area in addition to moderate white pulp hyperplasia in the spleen. The control group showed sever changes of inflammation, vacuolation, intestinal hemorrhage and congestion of the hepatic veins as well as hemosiderosis of the red pulp in the spleen. Conclusion. Albizia lebbeck leaf extract revealed to give an appropriate protection against inflammation as well as damage of virulent Klebsiella pneumoniae contagion in comparison to both of KWCSAg-KP and control groups.

HEMATOLOGICAL AND MOLECULAR STUDY OF TRYPANOSOMA EVANSI IN EXPERIMENTALLY INFECTION IN RABBITS

The lack of a sensitive diagnostic test for trypanosomasis in animals may hamper epidemiological data and control program implementation. This study aimed to detection of Trypanosoma evansi in rabbits that experimentally infected by this parasite which identified from camels of iraq by polymerase chain reaction. A study was conducted on 24 males rabbit divided into two groups (12 rabbits for each group). The first group was injected intra peritoneal (i/p) with 0.5 ml containing 1x105 trypanosome. The second group injected with distilled water and considered as control. At 7 and 10 days post infection, blood sample were collected from these rabbits. White blood cells count was conducted after 14 and 28 days post infection. The results showed that the 18S RNA and RoTat 1.2 genes related to T. evansi were identified .Furthermore ,there was significant elevation of Neutrophils ,Monocytes ,Lymphocytes ,Eosinophil and Basophils in infected rabbits compared with the control group. From this study we can conclude that PCR is a sensitive and effective technique for diagnosis of T.evansi through using 18S RNA and RoTat 1.2 genes. In addition ,WBC count was significantly elevated in an infected rabbits compared to the control. Whereas ,Lymphocyte was significantly higher in control group compared with infected group.

A Broad-specificity Neutralizing Nanobody against Hepatitis E Virus Capsid Protein.

Hepatitis E virus (HEV) is a worldwide zoonotic and public health concern. The study of HEV biology is helpful for designing viral vaccines and drugs. Nanobodies have recently been considered appealing materials for viral biological research. In this study, a Bactrian camel was immunized with capsid proteins from different genotypes (1, 3, 4, and avian) of HEV. Then, a phage library (6.3 × 108 individual clones) was constructed using peripheral blood lymphocytes from the immunized camel, and 12 nanobodies against the truncated capsid protein of genotype 3 HEV (g3-p239) were screened. g3-p239-Nb55 can cross-react with different genotypes of HEV and block Kernow-C1/P6 HEV from infecting HepG2/C3A cells. To our knowledge, the epitope recognized by g3-p239-Nb55 was determined to be a novel conformational epitope located on the surface of viral particles and highly conserved among different mammalian HEV isolates. Next, to increase the affinity and half-life of the nanobody, it was displayed on the surface of ferritin, which can self-assemble into a 24-subunit nanocage, namely, fenobody-55. The affinities of fenobody-55 to g3-p239 were ∼20 times greater than those of g3-p239-Nb55. In addition, the half-life of fenobody-55 was nine times greater than that of g3-p239-Nb55. G3-p239-Nb55 and fenobody-55 can block p239 attachment and Kernow-C1/P6 infection of HepG2/C3A cells. Fenobody-55 can completely neutralize HEV infection in rabbits when it is preincubated with nonenveloped HEV particles. Our study reported a case in which a nanobody neutralized HEV infection by preincubation, identified a (to our knowledge) novel and conserved conformational epitope of HEV, and provided new material for researching HEV biology.