Intracutaneous Tests Research Articles

Safety and Efficacy of VIT against Wasp Venom in Ultra-Rush Protocols in Patients Older Than 60 Years.

Allergen immunotherapy remains a widely recognized and widely used method for the treatment of selected allergic diseases. Currently, according to the European Academy Of Allergy and Clinical Immunology (EAACI) guidelines, venom immunotherapy (VIT) may be considered for patients over 60. Nevertheless, no separate studies have confirmed the efficacy and safety of this therapy. This study aimed to evaluate the short-term effectiveness of VIT against wasp allergens in an ultra-rush protocol for older patients compared to young patients. Among the 113 patients included in this study, 51 were older than 60 years (Group A), and 62 formed the control "young group" (age range: 18-35 years). All patients were desensitized to wasp venom using the ultra-rush protocol according to Muller and aqueous solutions of vaccines containing wasp venom. A basophil activation test (Basotest, Orpegen Pharma, Germany) and intracutaneous tests with dilutions of wasp allergen and specific IgE to extract wasp venom were performed at the start and after six months of VIT. The safety of VIT was assessed on the basis of the international Mueller scale. One hundred and eleven patients with confirmed wasp allergies completed six months of VIT: 51 participants over 60 years of age (Group A) and 60 young people (Group B). No systemic adverse reactions were observed during the VIT induction phase. However, large local reactions were noted in 17% of older patients and 20% of young patients at a similar level (p > 0.05). During maintenance VIT, two mild grade I systemic reactions were confirmed in young patients. These symptoms resolved spontaneously. There were no such reactions in older patients. The effectiveness of VIT was tested using BAT. There was a statistically significant reduction in CD63 reactivity in 86% of patients in Group A, and a comparable and substantial decrease in 84% of young patients in Group B. According to the BAT test, the mean reductions in the area under the curve (AUC) after six months of VIT were significant (p < 0.05) and comparable between Groups A and B: -6.52 vs. 7.21. VIT against wasp venom is safe and effective in short-term observation, and is comparable to that used for young patients.

Non-pyrogenicity and biocompatibility of parylene-coated magnetic bead implants.

Clinical grade magnetic bead implants have important applications in interfacing with the human body, providing contactless mechanical attachment or wireless communication through human tissue. We recently developed a new strategy, magnetomicrometry, that uses magnetic bead implants as passive communication devices to wirelessly sense muscle tissue lengths. We manufactured clinical-grade magnetic bead implants and verified their biocompatibility via intramuscular implantation, cytotoxicity, sensitization, and intracutaneous irritation testing. In this work, we test the pyrogenicity of the magnetic bead implants via a lagomorph model, and we test the biocompatibility of the magnetic bead implants via a full chemical characterization and toxicological risk assessment. Further, we test the cleaning, sterilization, and dry time of the devices that are used to deploy these magnetic bead implants. We find that the magnetic bead implants are non-pyrogenic and biocompatible, with the insertion device determined to be safe to clean, sterilize, and dry in a healthcare setting. These results provide confidence for the safe use of these magnetic bead implants in humans.

Clinical characteristics, allergic response to autologous semen, and desensitization in patients with postorgasmic illness syndrome.

Postorgasmic illness syndrome (POIS) is rare and includes a cluster of physical and cognitive symptoms that occur after ejaculation. The pathogenesis and effective treatments remain unclear. This study aimed to characterize the symptomatology of POIS, study the allergic response of autologous semen in patients and controls, and evaluate the effects of desensitization therapy. The clinical characteristics of 24 Chinese patients with POIS were analyzed. Skin prick tests, intracutaneous tests, and specific IgE detection were performed with autologous semen. Five patients were desensitized via subcutaneous injections of autologous semen. Evaluated outcomes included the clinical features of POIS; scores of the Self-rating Anxiety Scale (SAS), Self-rating Depression Scale (SDS), and visual analog scale (VAS) of symptoms; skin reactions; desensitization with diluted autologous seminal fluid; and the IgE reactivity patterns of immunoblotting and enzyme-linked immunosorbent assay in vitro. The most common symptom cluster was the general cluster, and the most prevalent symptoms were extreme fatigue and inattention. A total of 66.67% (14/21) of the patients had no symptoms or milder symptoms after nocturnal emission than after intercourse or masturbation. Of the patients, 87.5% (21/24) had psychiatric symptoms and 53.85% (7/13) had abnormal sex hormone levels. The SAS and SDS scores of the high and low VAS groups were significantly higher than those of the control group. Pearson analysis showed that the correlation coefficient between the SAS and VAS was 0.607 (P < .01) and that between the SDS and VAS was 0.490 (P < .05). The patients and healthy donors all had positive intracutaneous test results with their own semen, negative skin prick test results, and no IgE specific to autologous semen. Most patients (4/5) did not achieve ideal therapeutic effects with desensitization. Allergy is not the main pathogenesis of POIS, and desensitization with autologous semen is not effective for most patients. This project included the largest number of patients with POIS in China and assessed the allergic response to autologous semen and the effect of desensitization therapy. There is no objective method for evaluating the efficacy of desensitization with autologous semen. IgE-mediated semen allergy is not the main pathogenesis of POIS, and there is a positive chance that POIS is related to psychological factors. Most patients do not respond to desensitization with autologous semen, and POIS treatment should be individualized, especially in cases with uncertain causes.

Skin Tests versus Serology: Specific IgE May Suffice for Diagnosis of Vespid Venom Allergy and Follow-Up of Allergen Immunotherapy

Introduction: In adults, allergic reactions to insect stings are among the most frequent causes of anaphylaxis, a potentially life-threatening condition. Recurrent anaphylaxis following vespid stings may be prevented by allergen immunotherapy (AIT). The aim of this study was to evaluate the benefit of measuring venom-induced wheal area in intracutaneous skin tests (ICT), in comparison to various serological and clinical parameters, for the diagnosis of severe vespid venom allergy and during follow-up of AIT. Methods: We conducted a monocentric, retrospective evaluation of 170 patients undergoing AIT against vespid venoms. We scanned ICT wheals at baseline and at three time points after AIT initiation and measured wheal area using objective data analysis software. Results: We found that ICT histamine-induced and venom-induced wheal areas did not correlate. In addition, the venom-induced wheal area was independent from the minimal venom concentration required to elicit a wheal in an ICT and all other parameters. No correlation was found between wheal area and the severity of anaphylaxis. Wheal area standardized to the application of 0.1 μg/mL venom inversely correlated with anaphylaxis severity and positively correlated with venom-specific IgE levels. During AIT, mean areas of venom-induced wheals did not change. In contrast, venom-specific IgG and IgG4 levels, and the minimal venom concentration required to induce a positive ICT result increased, while the venom wheal area standardized to 0.1 μg/mL venom application and specific IgE levels decreased over time. Conclusion: Wheal area evaluation did not provide additional information over specific IgE analysis. We therefore recommend that ICTs are used only as a secondary measure for confirming serological test results.

Biaxial stretching of polytetrafluoroethylene in industrial scale to fabricate medical ePTFE membrane with node-fibril microstructure.

Expanded polytetrafluoroethylene (ePTFE) is promising in biomedical fields such as covered stents and plastic surgery owing to its excellent biocompatibility and mechanical properties. However, ePTFE material prepared by the traditional biaxial stretching process is with thicker middle and thinner sides due to the bowing effect, which poses a major problem in industrial-scale fabrication. To solve this problem, we design an olive-shaped winding roller to provide the middle part of the ePTFE tape with a greater longitudinal stretching amplitude than the two sides, so as to make up for the excessive longitudinal retraction tendency of the middle part when it is transversely stretched. The as-fabricated ePTFE membrane has, as designed, uniform thickness and node-fibril microstructure. In addition, we examine the effects of mass ratio of lubricant to PTFE powder, biaxial stretching ratio and sintering temperature on the performance of the resultant ePTFE membranes. Particularly, the relation between the internal microstructure of the ePTFE membrane and its mechanical properties is revealed. Besides stable mechanical properties, the sintered ePTFE membrane exhibits satisfactory biological properties. We make a series of biological assessments including in vitro hemolysis, coagulation, bacterial reverse mutation and in vivo thrombosis, intracutaneous reactivity test, pyrogen test and subchronic systemic toxicity test; all of the results meet the relevant international standards. The muscle implantation of the sintered ePTFE membrane into rabbits indicates acceptable inflammatory reactions of our sintered ePTFE membrane fabricated on industrial scale. Such a medical-grade raw material with the unique physical form and condensed-state microstructure is expected to afford an inert biomaterial potentially for stent-graft membrane.

Screening for tuberculosis infection in children and adolescents by two intracutaneous tests: with tuberculin and tuberculosis recombinant allergen (ESAT-6/CFP-10) in Moscow in 2021

The objective: to evaluate effectiveness of mass screening for tuberculosis infection in children and adolescents in Moscow using two different options according to age; to determine impact of the COVID-19 pandemic on effectiveness of screening campaign judging by incidence rates in children and adolescents.Subjects and Methods. In 2021, 758,634 children aged 0-7 years, or 99.2% of those to be screened, were screened using the Mantoux test. Should the reaction increase compared to the previous year, an additional test with the tuberculosis recombinant allergen (TRA) was performed. Children of 8-17 years old were screened only with TRA test. 1,070,961 people were examined, or 97.9% of those to be examined.Results. It has been demonstrated that the test with TRA can be used as a screening tool and effectively identify patients with a high risk of tuberculosis development. The preventive therapy received by those positively responding to TRA test resulted in almost no disease in them. The predominance of new cases with post-tuberculosis changes over new cases of active tuberculosis while the number of both is decreasing indicates the ability of the methods (TRA together with computed tomography) to detect minor forms of the active disease and post-tuberculous changes. In 2021 versus 2020, the number of children diagnosed with tuberculosis did not statistically significantly increase because of those who failed to be detected in 2020 due to incomplete coverage with screening related to spread of COVID-19. However, in 2021 the rates were lower than in 2019 which confirmed their positive change.Conclusion: Screening with TRA test is effective, easy to perform and can be used in primary health care.

Intracutaneous Skin Tests and Serum IgE Levels Cannot Predict the Grade of Anaphylaxis in Patients with Insect Venom Allergies.

BackgroundAllergies against Hymenoptera venoms are a major cause of severe anaphylaxis. Risk assessment for subjects with suspected allergy is difficult because there are currently no biomarkers that predict the likelihood of high-grade anaphylaxis other than several associated comorbidities.ObjectiveWe investigated the relationship between the severity of anaphylaxis and the results of intracutaneous skin tests (ICTs) together with serum levels of tryptase, total IgE, and venom-specific IgE, IgG, and IgG4.MethodsWe performed a retrospective evaluation of 194 patients who presented to a single medical center with allergies to bee venoms (Apis mellifera, Bombus spp.; n=24, 12.4%), vespid venoms (Vespula spp., Vespa spp., Polistes spp.; n=169, 87.1%), or both (n=1, 0.5%).ResultsIndex bee stings occurred earlier in the year than vespid stings, although the latter were reported more frequently overall. On average, subjects who previously experienced grade IV anaphylaxis required higher dosages of venom to yield positive ICTs than those who exhibited lower grade responses. Patients diagnosed with grade IV anaphylaxis exhibited significantly lower levels of venom-specific IgE and IgG and trended toward elevated levels of tryptase. No significant differences in average levels of venom-specific IgG4 and total IgE were observed.ConclusionOur findings reveal that intracutaneous skin testing and levels of venom-specific IgE do not predict the degree of anaphylaxis that develops in patients with venom allergy. Furthermore, the month of the index sting is not a reliable means to differentiate bee from vespid stings in patients presenting with an uncertain history.

Biocompatibility evaluation for the developed hydrogel wound dressing – ISO-10993-11 standards – in vitro and in vivo study

Assessment of biocompatibility for the developed wound dressing plays a significant role in translational studies. In the present research work, a wound dressing has been developed using gelatin, hyaluronic acid and chondroitin sulfate using EDC as crosslinker in a specific manner. The characterized hydrogel wound dressing was evaluated for its biocompatibility studies by means of ISO-10993-11 medical device rules and standards. Various parameters like skin sensitization test, acute systemic toxic test, implantation study, intracutaneous reactivity test, in vitro cytotoxicity test and bacterial reverse mutation test, were evaluated and the results demonstrated its safety for the pre-clinical investigation.

Manufacture and preliminary evaluation of acellular tooth roots as allografts for alveolar ridge augmentation.

Alveolar ridge augmentation can be used to obtain appropriate alveolar ridge for dental implantation. A variety of bone graft materials including autogenous bone, allograft, xenograft, and alloplastic material are used in alveolar ridge augmentation. Autogenous tooth-derived bone graft material has received much attention for the past few years, because the structure and physicochemical characteristics of tooth are similar to those of bones. Compared to autogenous tooth, allogenic tooth has the advantage of extensive resources. However, the problem of cell-derived immunological rejection of allogenic tooth remains unresolved. In the present study, acellular tooth root (ATR) is obtained by an innovative combination procedure. The biocompatibility of ATR is assessed using cytotoxicity test, hemolysis test, intracutaneous reactivity test, and acute systemic toxicity test. Osseointegration is evaluated in vivo by implanting ATR into the rat tibia defect as an allograft material. The results show that the ATR has fine biocompatibility, and there is an osseointegration between ATR and bone bed at 8 weeks post operation. This study demonstrates that the ATR could be used in alveolar ridge augmentation as a kind of new tooth-derived bone graft material.

Graphene-doped Poly(methyl-methacrylate) as an enhanced biopolymer for medical device and dental implant.

Graphene-doping procedure represents a useful procedure to improve the mechanical, physical and biological response of several PMMA-derived polymers and biomaterials for dental applications. The aim of the study was to evaluate measure water sorption, water solubility and tolerance trough the rabbit pyrogen testing pyrogen detection of Graphene doped Poly (methyl methacrylate) (PMMA) compared with PMMA as potential materials for dental implant device. A total of 8 aged and unaged samples Graphene doped PMMA and PMMA were tested for water sorption and water solubility of the specimens. The experimental condition was evaluated according to the ISO 20795-1:2013 protocol. The biopolymer tolerance was evaluated in vivo on animals through the pyrogen detection test, acute intracutaneous and systemic irritation test. After wet conditioning both of Graphene doped PMMA and PMMA reported an increase of the weight. All the experimental samples showed a drastic low level of water sorption and solubility. Graphene doped PMMA unaged specimens showed a stability of physical and optical feature after the treatment. The Graphene doped PMMA has not shown pyrogens, an intradermal and systemic irritant effect on animals. The Graphene-doped PMMA satisfy the standard requirements and provide a physical and optical stability of the compound after the treatment. Further in vivo findings are required for future clinical application of the compound.

Diaskintest for the diagnosis of bovine tuberculosis

The objective of the study: to compare the diagnostic value of intracutaneous tests with tuberculin and diaskintest for detection of tuberculosis in cattle.Subjects and methods. In this study, PPD tuberculin for mammals was used, it was made from M. bovis strain AN-5, manufactured by BIOK, and Diaskintest (recombinant tuberculous allergen, solution forintracutaneous administration) manufactured by ZAO FF Lecco, series 030307.Laboratory animals (guinea pigs, rabbits, chickens) and farm animals (pigs and cattle) were used in the study.Results. It has been established on laboratory animals that diaskintest does not cause any adverse events. When assessing sows sensitized with M. avium, it was found that the intracutaneous administration of PPD tuberculin to mammals resulted in up to 8.5% of positive reactions, while diaskintest was negative in all of them. Among cattle sensitized to non-tuberculous mycobacteria, intracutaneous administration of tuberculin for mammals revealed up to 4.6% of positive reactions, and diaskintest – up to 0.6%. In the farm with the unfavorable TB situation where animals infected with M. bovis were previously detected, when examining 177 cows, tuberculin test was positive in 102 (57.6%) of them, and diaskintest in 88 (49.7%). Diaskintest can be used for differential diagnosis of tuberculosis and sensitization by non-tuberculous mycobacteria in pigs and cattle.

Allergic activity and specificity of tuberculin preparations with 30-50% of weakly secreted mycobacterial antigens of tuberculosis

Bovine tuberculosis remains a global problem. An intracutaneous test with tuberculin is the main method for determining the status of herds, which poses special requirements for the activity and specificity. The basis of cotemporal tuberculins are antigens of tuberculosis mycobacteria easily secreted to the liquid synthetic medium during growth, but a range of antigens with a low secretion index are in composition of tuberculins in small quantities. The purpose of the research is to obtain weakly secreted antigens from a production waste – autoclaved bacterial mass of production strain of tuberculosis mycobacteria (MTB) using ultrasound and nonionic detergent, to study the diagnostic properties of tuberculosis with 30-50% of such antigens. It has been determined that autoclaved bacterial mass of industrial MBT strain, which is a waste of tuberculin production, can be an additional source of tuberculoproteins, which are low-secreting (LS) MBT antigens, which in an equivalent dose are about 30% more active compared to standard tuberculin based on easily secreted antigens and is not inferior in terms of species specificity. Whereas, up to 50% of purified LS of tuberculoproteins from the bacterial mass can be included in tuberculin composition. The obtained preparation is not reactogenic, in an equivalent dose it does not differ in terms of activity from the international standard for PPD of tuberculin, but surpasses it in terms of species specificity. It has been shown that in herds with an undetermined tuberculosis status, 2.2 times more cows respond to tuberculins with 30-50% of purified LS tuberculoproteins compared to standard preparations based on easily secreted antigens of tuberculosis mycobacterium. Profound studies of reacting cows using methods for detecting the genome of tuberculosis mycobacterium and bacteriological markers of tuberculosis infection have confirmed the presence of latent tuberculosis infection in cow body. The inclusion of up to 50% of tuberculoproteins from the bacterial mass in tuberculin increases the diagnostic properties of the target product and significantly reduces its price cost.

The suitability of reconstructed human epidermis models for medical device irritation assessment: A comparison of In Vitro and In Vivo testing results

The ISO 10993 standards on biocompatibility assessment of medical devices discourage the use of animal tests when reliable and validated in vitro methods are available. A round robin validation study of in vitro reconstructed human epidermis (RhE) assays was performed as potential replacements for rabbit skin irritation testing. The RhE assays were able to accurately identify strong irritants in dilute medical device extracts. However, there was some uncertainty about whether RhE tissues accurately predicted the results of the rabbit skin patch or intracutaneous irritation test. To address that question, this paper presents in vivo data from the round robin and subsequent follow-up studies. The follow-up studies included simultaneous in vitro RhE model and in vivo testing of round robin polymer samples and the results of dual in vitro/in vivo testing of currently marketed medical device components/materials. Our results show for the first time that for both pure chemicals and medical device extracts the intracutaneous rabbit test is more sensitive to detect irritant activity than the rabbit skin patch test. The studies showed that the RhE models produced results that were essentially equivalent to those from the intracutaneous rabbit skin irritation test. Therefore, it is concluded that RhE in vitro models are acceptable replacements for the in vivo rabbit intracutaneous irritation test for evaluating the irritant potential of medical devices.

Hypersensitivity reactions to non-steroidal anti-inflammatory drugs: results of an Austrian cohort study

Summary Background Hypersensitivity to non-steroidal anti-inflammatory drugs (NSAIDs) is the second most common cause of drug hypersensitivity. Despite the importance of NSAIDs in routine analgesia only few studies have systematically addressed the question of tolerability in hypersensitive patients. Methods The authors retrospectively analysed 398 patients that were treated at the Department of Dermatology, Kepler University Hospital Linz, Austria, in the period 2012–2016 with a clinical history of NSAID hypersensitivity. Skin tests (skin prick and intracutaneous tests) to common NSAIDs were performed, followed by single-blinded, placebo-controlled drug challenge with either the culprit drug or an alternative NSAID. Results A total of 361 patients were subjected to skin testing. Of these, 25 patients (6.3%) showed a positive reaction to the culprit drug. According to the severity of the reaction in the medical history, 87 patients were exposed orally to the culprit drug (oral provocation test, OPT) after negative skin test and 255 patients received OPT with alternative NSAIDs according to established protocols. OPT with the culprit drug resulted in hypersensitivity reactions in 12 patients (13.79%). In terms of alternative NSAID testing, the three most commonly tested drugs were lornoxicam (192 OPTs), acetaminophen (156 OPTs) and celecoxib (133 OPTs) with tolerability rates in respectively 88.54% (hypersensitivity reactions, 11.46%), 92.31% (hypersensitivity reactions, 7.69%) and 91.73% (hypersensitivity reactions, 8.27%) of cases. Conclusion OPT with alternative NSAIDs are useful in patients with NSAID hypersensitivity as tolerability varies between the individual substances.

Skin testing in allergy.

Skin tests are used in addition to a directed history and physical examination to exclude or confirm immunoglobulin E (IgE) mediated diseases, such as allergic rhinitis, asthma, and anaphylaxis, to aeroallergens, foods, insect venoms, and certain drugs. There are two types of skin testing used in clinical practice: percutaneous testing (prick or puncture) and intracutaneous testing (intradermal). Prick testing involves introducing a needle into the upper layers of the skin through a drop of allergen extract that has been placed on the skin and gently lifting the epidermis up. Various devices are available for prick testing. Intracutaneous (intradermal) testing involves injecting a small amount of allergen into the dermis. The release of preformed histamine from mast cells causes increased vascular permeability via smooth-muscle contraction and development of a wheal; inflammatory mediators initiate a neural reflex, which causes vasodilatation, which leads to erythema (the flare). Prick testing methods are the initial technique for detecting the presence of IgE. These may correlate better with clinical sensitivity and are more specific but less sensitive than intradermal testing. Sites of skin testing include the back and the volar aspect of the arm. By skin testing on the arm, the patient can witness the emergence and often sense the pruritus of the skin test reaction. Because more patients are sensitized (have IgE antibodies and positive skin test reactions) than have corresponding symptoms, the diagnosis of allergy can be made only by correlating skin testing results with the presence of clinical symptoms.

Biocompatibility of a New Kind of Polyvinyl Alcohol Embolic Microspheres: In Vitro and In Vivo Evaluation.

The aim of this study is to investigate the biocompatibility of polyvinyl alcohol (PVA) embolic microspheres by in vivo and in vitro evaluations. Two specifications of PVA microspheres including colorless microspheres (1g microspheres with 7mL 0.9% sodium chloride (SC) per vial, size: 500-700µm) and blue microspheres (2g microspheres with 7mL 0.9% SC per vial, size: 500-700µm) were assessed for biocompatibility. The vitro cytotoxicity was evaluated in L929 cells by MTT assay. Acute systemic toxicity and 28-repeat dose intravenous subchronic toxicity were assessed in 20 ICR mice and 40 SD rates, respectively. Skin sensitization was conducted in 30 adult albino guinea pigs by maximization test, in addition, intracutaneous reaction test was performed in New Zealand white rabbits. Hemolysis ratio of PVA microspheres was evaluated with rabbit blood. Moreover, test for genotoxicity was assessed by bacterial reverse mutation test and mouse lymphoma mutagenesis assay. No cytotoxicity, hemolysis, or acute toxicity of PVA microspheres was found, and slight fluctuations of biochemical indexes were observed in test of 28-day repeat dose intravenous subchronic toxicity, while these changes remained within our historical permitted range. Maximization test and intracutaneous reactivity test disclosed no irritation to skin or tissues. According to bacterial reverse mutation test and mouse lymphoma mutagenesis assay, no genotoxicity of PVA microspheres was observed. PVA microspheres showed excellent biocompatibility both in vivo and in vitro, and they were promising embolic materials for drug-eluting beads transarterial chemoembolization (DEB-TACE) therapy.

Biocompatibility Assessments of Surgical sutures: Intracutaneous Reactivity Test in New Zealand White Rabbits

Biocompatibility Assessments of Surgical sutures: Intracutaneous Reactivity Test in New Zealand White Rabbits

Food allergies in weaned piglets in experiment and spontaneous occurrence

Food allergies in weaned piglets in experiment and spontaneous occurrence

Antibiotic Use After Removal of Penicillin Allergy Label

D Vyles, A Chiu, J Routes. Pediatrics. 2018;141(5):e20173466 To evaluate the clinical and economic impact of negative penicillin testing results for children with a previous penicillin allergy label. This study included caregivers and primary care providers (PCPs) of 100 children between the ages of 4 and 18 years with negative test results for penicillin allergy after percutaneous, intracutaneous testing and an oral challenge. A follow-up case series investigation was performed on 100 children with “low-risk” allergy symptoms who had a negative penicillin allergy evaluation result. Low-risk symptoms included a nonurticarial rash, itching, diarrhea, and vomiting. The study authors hypothesized that no serious allergic reactions would occur with reexposure and that prescribing practices would change as a result of testing. A brief telephone survey was administered to parents and PCPs. Parents were questioned regarding antibiotic use since penicillin testing, any recent allergic reactions, parental comfort level with future penicillin use, …

α-hemihydrate calcium sulfate/octacalcium phosphate combined with sodium hyaluronate promotes bone marrow-derived mesenchymal stem cell osteogenesis in vitro and in vivo.

PurposeThe aims of this research were to combine α-hemihydrate calcium sulfate/octacalcium phosphate (α-CSH/OCP) with sodium hyaluronate (SH) or SH sulfate (SHS) to determine whether these composites can be used as a new type of bone repair material. This study may provide a theoretical basis and new ideas for the construction of active bone repair materials and their clinical application.MethodsIn this study, we combined α-CSH/OCP with SH or SHS. Scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and the wettability test were performed, and porosity, setting time, in vitro degradation, and the mechanical properties of these composite materials were analyzed to evaluate the ultrastructural and physicochemical properties. We evaluated the histocompatibility of these composites by MTT assay, hemolysis, acute toxicity, and pyrogenic and intracutaneous stimulation tests. In addition, the osteogenic differentiation ability of these materials was detected in vitro using Western blot analysis and in vivo using an animal model of bone defect.ResultsThe α-CSH/OCP/SH composite had a compressive strength of 13.72 MPa, a porous rate of 27.45%, and the 28-day degradation rate of 64%. The MTT assay results showed that the relative proliferation rates of the α-CSH/OCP/SH group were greater than 90%. The results of the α-CSH/OCP/SH composite in the hemolysis, acute toxicity, pyrogenic, and intracutaneous stimulation tests were within the normal range. Western blot analysis indicated that the expression of bone extracellular matrix (ECM) proteins was notably upregulated and always higher in the α-CSH/OCP/SH group than in the other groups. XRD of the rabbit radius-defect model indicated that bone healing in the area implanted with α-CSH/OCP/SH was excellent approximately 9 weeks after repair.Conclusionα-CSH/OCP/SH has very good biocompatibility and exhibits clear advantages in the induction of bone regeneration and self-repair, and this compound shows promise in the field of bone tissue engineering.