scholarly journals Immunogenicity of Streptococcus pneumoniae 74 kDa Surface Protein in Rabbit Model

2016 ◽  
pp. 25-28
Author(s):  
Zeenat Jahan ◽  
Iztiba Mallik Deeba ◽  
Shahina Akter ◽  
Tasmina Rahman ◽  
Ashikun Nabi ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Extraction Procedure ◽  
Rabbit Model ◽  
Surface Protein ◽  
Immunoblot Analysis ◽  
High Titre ◽  
Control Group ◽  
Nitrocellulose Membrane ◽  
Immunoblot Assay ◽  
High Titre Antibody

Immunogenicity of a pneumococcal 74 kDa surface protein in the rabbit model was investigated in this study. For this, Streptococcus pneumoniae serotype 7F was collected and water extraction procedure was applied for the preparation of surface materials, which was used for further isolation of the 74 kDa surface protein. Rabbits were immunized with the sonicated nitrocellulose membrane containing the 74 kDa surface protein and the control group of rabbits was injected with same concentration of sonicated nitrocellulose membrane only. The antibody response against the 74 kDa surface protein was evaluated by both ELISA and immunoblot assay. Sera collected from the 74 kDa surface protein immunized rabbits were examined and the high titre (1:1600) ELISA values (OD490) indicated the production of adequate amounts of anti-74 kDa antibodies in the rabbits. In the immunoblot analysis, a single antigenic band was obtained on the nitrocellulose membrane treated with sera obtained from rabbits immunized with the 74 kDa surface protein. The high titre antibody production in the rabbits indicates the immunogenicity of the 74 kDa surface protein in rabbit model.Bangladesh J Microbiol, Volume 31, Number 1-2,June-Dec 2014, pp 25-28

scholarly journals The Effects of PspC on Complement-Mediated Immunity to Streptococcus pneumoniae Vary with Strain Background and Capsular Serotype

2009 ◽  
Vol 78 (1) ◽  
pp. 283-292 ◽  
Author(s):  
Jose Yuste ◽  
Suneeta Khandavilli ◽  
Naadir Ansari ◽  
Kairya Muttardi ◽  
Laura Ismail ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Allelic Variation ◽  
Degradation Products ◽  
Alternative Pathway ◽  
Surface Protein ◽  
Immunoblot Analysis ◽  
Factor H ◽  
Negative Regulator ◽  
Complement Activity ◽  
Strain Background

ABSTRACT Streptococcus pneumoniae may evade complement activity by binding of factor H (FH), a negative regulator of the alternative pathway, to the surface protein PspC. However, existing data on the effects of FH binding to PspC on complement activity are conflicting, and there is also considerable allelic variation in PspC structure between S. pneumoniae strains that may influence PspC-dependent effects on complement. We have investigated interactions with complement for several S. pneumoniae strains in which the gene encoding PspC has been deleted. The degree of FH binding varied between strains and was entirely dependent on PspC for seven strains. Data obtained with TIGR4 strains expressing different capsular serotypes suggest that FH binding is affected by capsular serotype. Results of immunoblot analysis for C3 degradation products and iC3b deposition assays suggested that FH bound to PspC retained functional activity, but loss of PspC had strikingly varied effects on C3b/iC3b deposition on S. pneumoniae, with large increases on serotype 4, 6A, 6B, and 9V strains but only small increases or even decreases on serotype 2, 3, 17, and 23F strains. Repeating C3b/iC3b assays with TIGR4 strains expressing different capsular serotypes suggested that differences in the effect of PspC on C3b/iC3b deposition were largely independent of capsular serotype and depend on strain background. However, data obtained from infection in complement-deficient mice demonstrated that differences between strains in the effects of PspC on complement surprisingly did not influence the development of septicemia.

scholarly journals 168. Efficacy of the Novel gwt1 Inhibitor APX2039 in a Rabbit Model of cryptococcus Meningitis

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S213-S213
Author(s):  
Karen J Shaw ◽  
Charles D Giamberardino ◽  
Quinlyn A Soltow ◽  
Jennifer Tenor ◽  
Dena Toffaletti ◽  
...  
Keyword(s):  
Brain Tissue ◽  
Oral Treatment ◽  
Treatment Options ◽  
Rabbit Model ◽  
Experimental Period ◽  
Control Group ◽  
Log10 Reduction ◽  
Research Support ◽  
Rapid Reduction ◽  
Geographical Regions

Abstract Background Cryptococcal meningitis (CM), caused primarily by Cryptococcus neoformans, is uniformly fatal if not treated. Treatment options are limited especially in resource-poor geographical regions, and mortality rates remain high despite current therapies. New oral treatment options are needed that demonstrate rapid reductions in CFU in CSF and brain tissue. APX2039 is a novel inhibitor of the fungal Gwt1 enzyme, which catalyzes an early step in glycosylphosphatidyl inositol (GPI) anchor biosynthesis. It is highly active against both C. neoformans and C. gattii and has previously demonstrated significant efficacy in a mouse delayed-treatment model of CM. CSF Fungal Burden in Rabbits Methods Male New Zealand White rabbits were inoculated with C. neoformans H99 (1.4 ×106 CFU) directly into the cisterna magna. Rabbits were immunosuppressed with cortisone acetate at 7.5 mg/kg (i.m.), starting on Day -1 relative to inoculation and then administered drug daily throughout the 14-day experimental period. Treatment was initiated on Day 2 postinfection and continued through Day 14 consisting of: 50 mg/kg APX2039 PO (BID), 80 mg/kg fluconazole (FLU) PO (QD), c) 1 mg/kg amphotericin B deoxycholate (AMB) IV (QD); and vehicle control. CSF was removed via an intracisternal tap on Days 2, 7, 10 and 14 post-infection and CFU/ml was assessed. Animals were sacrificed on Day 14 and CFU/g brain tissue was assessed. Results APX2039 demonstrated rapid reduction in CFU in both CSF and brain tissue. The range in CFU values in rabbit CSF is shown (Figure). Reductions in CFU were statistically different from the control group for all treatment groups. APX2039 was also different from both FLU and AMB and resulted in sterilization in CSF by Day 10. Brain harvested on Day 14 demonstrated a reduction in CFU/g tissue vs control of 1.8 log10 and 3.4 log10 for FLU and AMB, respectively, while a > 6 log10 reduction (tissue sterilization) was observed for APX2039. Conclusion APX2039 demonstrated potent efficacy in a rabbit model of CM. The more rapid clearance in CSF than either AMB or FLU, as well as > 6 log10 reduction in brain CFU highlights the unique properties of this drug, warranting further investigation of this molecule for the treatment of CM. Disclosures Karen J. Shaw, PhD, Amplyx (Consultant)Forge Therapeutics (Consultant) Charles D. Giamberardino, Jr., MR, Box (Shareholder) John R. Perfect, MD, amplyx (Grant/Research Support)astellas (Grant/Research Support)astellas (Grant/Research Support)

Parathyroid hormone promotes cartilage healing after free reduction of mandibular condylar fractures by upregulating Sox9

2021 ◽  
pp. 153537022110271
Author(s):  
Yuanyuan Jia ◽  
Liuqin Xie ◽  
Zhenglong Tang ◽  
Dongxiang Wang ◽  
Yun Hu ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Internal Fixation ◽  
Early Stage ◽  
Rabbit Model ◽  
Mandibular Condyle ◽  
Fracture Site ◽  
Control Group ◽  
Condylar Cartilage ◽  
Cartilage Healing ◽  
Experimental Group

After high fractures of the mandibular condyle, the insufficient blood supply to the condyle often leads to poor bone and cartilage repair ability and poor clinical outcome. Parathyroid hormone (PTH) can promote the bone formation and mineralization of mandibular fracture, but its effects on cartilage healing after the free reduction and internal fixation of high fractures of the mandibular condyle are unknown. In this study, a rabbit model of free reduction and internal fixation of high fractures of the mandibular condyle was established, and the effects and mechanisms of PTH on condylar cartilage healing were explored. Forty-eight specific-pathogen-free (SPF) grade rabbits were randomly divided into two groups. In the experimental group, PTH was injected subcutaneously at 20 µg/kg (PTH (1–34)) every other day, and in the control group, PTH was replaced with 1 ml saline. The healing cartilages were assessed at postoperative days 7, 14, 21, and 28. Observation of gross specimens, hematoxylin eosin staining and Safranin O/fast green staining found that every-other-day subcutaneous injection of PTH at 20 µg/kg promoted healing of condylar cartilage and subchondral osteogenesis in the fracture site. Immunohistochemistry and polymerase chain reaction showed that PTH significantly upregulated the chondrogenic genes Sox9 and Col2a1 in the cartilage fracture site within 7–21 postoperative days in the experimental group than those in the control group, while it downregulated the cartilage inflammation gene matrix metalloproteinase-13 and chondrocyte terminal differentiation gene ColX. In summary, exogenous PTH can stimulate the formation of cartilage matrix by triggering Sox9 expression at the early stage of cartilage healing, and it provides a potential therapeutic protocol for high fractures of the mandibular condyle.

Delivery of CD151 by Ultrasound Microbubbles in Rabbit Myocardial Infarction

Cardiology ◽  
2016 ◽  
Vol 135 (4) ◽  
pp. 221-227 ◽  
Author(s):  
Shao-Ling Yang ◽  
Ke-Qiang Tang ◽  
Jun-Jia Tao ◽  
Ai-Hong Wan ◽  
Yan-Duan Lin ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Heart Function ◽  
Rabbit Model ◽  
Physiological Saline ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Control Group ◽  
Therapeutic Effects ◽  
Ventricular Ejection Fraction ◽  
Cluster Of Differentiation

Objectives: We aimed to evaluate whether ultrasound (US) and microbubble-mediated delivery of Cluster of Differentiation 151 (CD151) could enhance the therapeutic effects of CD151 on myocardial infarction (MI). Methods: A rabbit model of MI was established by a modified Fujita method. Then, 50 MI rabbits were randomly divided into 5 groups, including G1 (CD151 plasmid and physiological saline in the presence of US); G2 (CD151 and Sonovue in the presence of US); G3 (CD151 and Sonovue in the absence of US); G4 (Sonovue in the absence of US), and a control group (physiological saline in the absence of US). After 14 days of treatment, the expression of CD151 was detected by Western blot. Besides, vessel density of peri-infarcted myocardium was measured by immunohistochemistry, and cardiac function was analyzed by echocardiography. Results: The rabbit model of MI was established successfully. CD151 injection increased the expression of CD151 and microvessel density in the myocardium of MI rabbits. Heart function was significantly improved by CD151, which exhibited increased left ventricular ejection fraction, left ventricular fractional shortening and a reduced Tei index. Besides, US Sonovue significantly increased the expression efficiency of CD151. Conclusion: US microbubble was an effective vector for CD151 delivery. CD151 might be an effective therapeutic target for MI.

scholarly journals Influence of the Thermal Treatment to Address a Better Osseointegration of Ti6Al4V Dental Implants: Histological and Histomorphometrical Study in a Rabbit Model

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Antonio Scarano ◽  
Ezio Crocetta ◽  
Alessandro Quaranta ◽  
Felice Lorusso
Keyword(s):  
Thermal Treatment ◽  
Dental Implants ◽  
Bone Healing ◽  
Rabbit Model ◽  
Titanium Implants ◽  
Control Group ◽  
Left Femur ◽  
Bone Response ◽  
First Choice ◽  
Significant Difference

Background. Pure titanium continues to be the first choice for dental implants and represents the gold standard for their biocompatibility and physical and mechanical characteristics, while the titanium alloy (Ti6Al4V) has good mechanical properties. The surface structure of the titanium oxide layer formation on the surface influences and improves the bone response around dental implants. Purpose. The purpose of this study is to evaluate the influence of a thermal treatment of Ti6Al4V implant surfaces and the bone healing response in a rabbit model. Methods. Altogether sixteen implants with same design were inserted into the distal femoral metaphysis. A screw (13 mm long, 4 mm in diameter) was inserted in an implant bed. Each rabbit received two implants, one in the left femur and one in the right femur. The samples were histologically and histomorphometrically evaluated at 8 weeks. Results. A statistically significant difference (p = 0.000034) was present histologically in the percentages of bone-implant contact (BIC) between the test group (BIC = 69.25±4.49%.) and control group (BIC = 56.25 ± 4.8%) by one-way analysis of variance (ANOVA). Significance was set at p ≤ 0.05. Conclusions. The outcome of the present study indicates a novel approach to improving bone healing around titanium implants.

scholarly journals DNA vaccines expressing pneumococcal surface protein A (PspA) elicit protection levels comparable to recombinant protein

2006 ◽  
Vol 55 (4) ◽  
pp. 375-378 ◽  
Author(s):  
Daniela M. Ferreira ◽  
Eliane N. Miyaji ◽  
Maria Leonor S. Oliveira ◽  
Michelle Darrieux ◽  
Ana Paula M. Arêas ◽  
...  
Keyword(s):  
Streptococcus Pneumoniae ◽  
Recombinant Protein ◽  
Dna Vaccines ◽  
Protein A ◽  
Surface Protein ◽  
Humoral Response ◽  
Cost Effective ◽  
Promising Candidate ◽  
Pneumococcal Surface Protein A ◽  
Antibody Levels

Pneumococcal surface protein A (PspA) is a promising candidate for the development of cost-effective vaccines against Streptococcus pneumoniae. In the present study, BALB/c mice were immunized with DNA vaccine vectors expressing the N-terminal region of PspA. Animals immunized with a vector expressing secreted PspA developed higher levels of antibody than mice immunized with the vector expressing the antigen in the cytosol. However, both immunogens elicited similar levels of protection against intraperitoneal challenge. Furthermore, immunization with exactly the same fragment in the form of a recombinant protein, with aluminium hydroxide as an adjuvant, elicited even higher antibody levels, but this increased humoral response did not correlate with enhanced protection. These results show that DNA vaccines expressing PspA are able to elicit protection levels comparable to recombinant protein, even though total anti-PspA IgG response is considerably lower.

scholarly journals Pneumococcal Surface Protein C Contributes to Sepsis Caused by Streptococcus pneumoniae in Mice

2004 ◽  
Vol 72 (5) ◽  
pp. 3077-3080 ◽  
Author(s):  
Francesco Iannelli ◽  
Damiana Chiavolini ◽  
Susanna Ricci ◽  
Marco Rinaldo Oggioni ◽  
Gianni Pozzi
Keyword(s):  
Streptococcus Pneumoniae ◽  
Protein C ◽  
Lethal Dose ◽  
Surface Protein ◽  
Infection Model ◽  
Wild Type ◽  
Mutant Strains ◽  
Type 3

ABSTRACT The role of pneumococcal surface protein C (PspC; also called SpsA, CbpA, and Hic) in sepsis by Streptococcus pneumoniae was investigated in a murine infection model. The pspC gene was deleted in strains D39 (type 2) and A66 (type 3), and the mutants were tested by being injected intravenously into mice. The animals infected with the mutant strains showed a significant increase in survival, with the 50% lethal dose up to 250-fold higher than that for the wild type. Our findings indicate that PspC affords a decisive contribution to sepsis development.

Atelocollagen Enhances the Healing of Rotator Cuff Tendon in Rabbit Model

2017 ◽  
Vol 45 (9) ◽  
pp. 2019-2027 ◽  
Author(s):  
Dong-Sam Suh ◽  
Jun-Keun Lee ◽  
Ji-Chul Yoo ◽  
Sang-Hun Woo ◽  
Ga-Ram Kim ◽  
...  
Keyword(s):  
Rotator Cuff ◽  
Rapid Development ◽  
Rabbit Model ◽  
Supraspinatus Tendon ◽  
Histological Evaluation ◽  
Control Group ◽  
Patch Type ◽  
Load To Failure ◽  
Cuff Repair ◽  
Experimental Group

Background: Failure of rotator cuff healing is a common complication despite the rapid development of surgical repair techniques for the torn rotator cuff. Purpose: To verify the effect of atelocollagen on tendon-to-bone healing in the rabbit supraspinatus tendon compared with conventional cuff repair. Study Design: Controlled laboratory study. Methods: A tear of the supraspinatus tendon was created and repaired in 46 New Zealand White rabbits. They were then randomly allocated into 2 groups (23 rabbits per group; 15 for histological and 8 for biomechanical test). In the experimental group, patch-type atelocollagen was implanted between bone and tendon during repair; in the control group, the torn tendon was repaired without atelocollagen. Each opposite shoulder served as a sham (tendon was exposed only). Histological evaluation was performed at 4, 8, and 12 weeks. Biomechanical tensile strength was tested 12 weeks after surgery. Results: Histological evaluation scores of the experimental group (4.0 ± 1.0) were significantly superior to those of the control group (7.7 ± 2.7) at 12 weeks ( P = .005). The load to failure was significantly higher in the experimental group (51.4 ± 3.9 N) than in the control group (36.4 ± 5.9 N) ( P = .001). Conclusion: Histological and biomechanical studies demonstrated better results in the experimental group using atelocollagen in a rabbit model of the supraspinatus tendon tear. Clinical Relevance: Atelocollagen patch could be used in the cuff repair site to enhance healing.

scholarly journals Effect of Acute Increases in Intraocular Pressure on Corneal Pachymetry in Rabbit Eyes Treated with Timolol Maleate

2018 ◽  
Vol 12 (1) ◽  
pp. 314-321
Author(s):  
Cristina Sánchez-Barahona ◽  
Gema Bolívar ◽  
Dimitrios G. Mikropoulos ◽  
Anastasios G. Konstas ◽  
Miguel A. Teus
Keyword(s):  
Intraocular Pressure ◽  
Anterior Chamber ◽  
Central Corneal Thickness ◽  
Corneal Thickness ◽  
Rabbit Model ◽  
Controlled Study ◽  
Control Group ◽  
Study Group ◽  
Timolol Maleate

Objective: To evaluate in an in vivo rabbit model, the effect of topical timolol maleate therapy on the central corneal thickness response to acute intraocular pressure increases. Method: In this prospective and interventional controlled study, the central corneal thickness and intraocular pressure were measured in vivo in 12 rabbit eyes treated with topical timolol maleate for 1 month and in 12 controls at baseline, and after the intraocular pressure (measured by direct cannulation of the anterior chamber) was increased to 15 and 30 mmHg using a forced saline infusion into the anterior chamber. Results: There were no significant differences in the basal central corneal thickness values (control group, 373.2±12.9 µm; study group, 377.5±19.2 µm, p=0.5) or the central corneal thickness values when the intraocular pressure was increased to 15 mmHg (control group, 335.2±14.3 µm; study group, 330.0±32.1 µm, p=0.6) and to 30 mmHg (study group, 318.8±25.3 µm; control group, 329.8±21.0 µm, p=0.3). Conclusion: Rabbit corneas treated with topical timolol maleate for 1 month did not show a strain response to acute intraocular pressure increases that differed from control eyes. This is in contrast to a previous finding in which rabbit eyes treated with prostaglandin analogues had a greater decrease in central corneal thickness in response to a sudden intraocular pressure increase compared with untreated corneas.

scholarly journals A Listeria monocytogenes-Based Vaccine Formulation Reduces Vertical Transmission and Leads to Enhanced Pup Survival in a Pregnant Neosporosis Mouse Model

Vaccines ◽  
2021 ◽  
Vol 9 (12) ◽  
pp. 1400
Author(s):  
Dennis Imhof ◽  
William Robert Pownall ◽  
Camille Monney ◽  
Anna Oevermann ◽  
Andrew Hemphill
Keyword(s):  
Listeria Monocytogenes ◽  
Mouse Model ◽  
Neospora Caninum ◽  
Post Partum ◽  
Systemic Infection ◽  
Surface Protein ◽  
Control Group ◽  
Protective Effects ◽  
Igg Antibody ◽  
Th2 Response

The apicomplexan parasite Neospora caninum is the worldwide leading cause of abortion and stillbirth in cattle. An attenuated mutant Listeria monocytogenes strain (Lm3Dx) was engineered by deleting the virulence genes actA, inlA, and inlB in order to avoid systemic infection and to target the vector to antigen-presenting cells (APCs). Insertion of sag1, coding for the major surface protein NcSAG1 of N. caninum, yielded the vaccine strain Lm3Dx_NcSAG1. The efficacy of Lm3Dx_NcSAG1 was assessed by inoculating 1 × 105, 1 × 106, or 1 × 107 CFU of Lm3Dx_NcSAG1 into female BALB/c mice by intramuscular injection three times at two-week intervals, and subsequent challenge with 1 × 105N. caninum tachyzoites of the highly virulent NcSpain-7 strain on day 7 of pregnancy. Dose-dependent protective effects were seen, with a postnatal offspring survival rate of 67% in the group treated with 1 × 107 CFU of Lm3Dx_NcSAG1 compared to 5% survival in the non-vaccinated control group. At euthanasia (25 days post-partum), IgG antibody titers were significantly decreased in the groups receiving the two higher doses and cytokines recall responses in splenocyte culture supernatants (IFN-γ, IL-4, and IL-10) were increased in the vaccinated groups. Thus, Lm3Dx_NcSAG1 induces immune-protective effects associated with a balanced Th1/Th2 response in a pregnant neosporosis mouse model and should be further assessed in ruminant models.

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