In vitro bioactivity and degradation of polycaprolactone composites containing silicate fillers

In spite of numerous publications on the potential use of combinations of polycaprolactone (PCL)/bioactive fillers for bone regeneration, little information exists on the assessment of solid, nonporous composites prepared via solventless routes and consisting of unmodified, slowly degrading homopolymer with relatively low amounts of reactive fillers such as bioglass or calcium silicate (CS). Thus, composites of PCL with commercial CS and a bioactive glass (BG45S5) at 30wt.% were produced by melt mixing in a twin screw extruder. Neat fillers, PCL and their composites were immersed in simulated body fluid (SBF) and phosphate buffer saline and tested for in vitro bioactivity and degradation, respectively, over a 4 month period. Testing methods included scanning electron microscopy with energy dispersive X-ray analysis, X-ray diffraction (XRD), elemental analysis and weight and pH changes before and after immersion. Experiments with neat fillers indicated fast growth of calcium phosphate minerals having different textures; they included clusters and globules of mineral precipitates as well as needle-shaped nanosized crystallites and possibly other calcium phosphate structures with varying Ca/P ratio. The bioactive glass composite initially showed fast growth of the precipitated minerals and partial surface coverage after 1 week, whereas in the CS composite, growth and surface coverage increased as a function of immersion time (over a period of 4 weeks) in the SBF solution. XRD results showed early appearance (1 week) of hydroxyapatite for both types of composites with differences attributed to different dissolution rates and different surface reactions of the fillers. Both fillers appeared to enhance the hydrolytic degradation of the matrix. Overall, the limited observed bioactivity of both composites within the test period may be related to the hydrophobicity of the matrix, insufficient ionic activity since SBF was not replenished and the relatively low content of the low surface areas fillers. Optimization of filler properties, such as surface/volume ratio, surface chemistry and size range, appears as a most important factor that would provide, at the required high filler volume fractions, a balance of melt processability and bioactivity.     

In vitro characterization of polycaprolactone matrices generated in aqueous media

In this study, a novel process of dissolving polycaprolactone (PCL) matrices in glacial acetic acid was explored in which matrices spontaneously formed upon contact with water. Scanning electron microscopy analysis showed rough architecture and holes on the self-assembled matrix relative to matrices formed after dissolving in chloroform. Immersion in the gelatin solution reduced its roughness and number of micropores. Atomic force microscopy (AFM) analysis confirmed the increased roughness of the self-assembled matrices. The roughness of the matrices decreased after incubation in 1 N NaOH for 10 min. AFM analysis also revealed that the self-assembled matrix had a net positive surface charge, whereas chloroform–cast matrix had a negative surface charge. The surface charge of self-assembled matrix after immersion in gelatin changed to negative. However, incubation in NaOH did not affect the surface charge. The tensile properties were tested in both the dry state (25 °C) and the wet state (37 °C) by immersion in phosphate-buffered saline. Self-assembled matrix had lower elastic modulus, break stress and break strain than chloroform–cast matrix in both states. The elastic modulus in the wet condition was reduced by half in self-assembled matrix but tensile strain increased. Samples were further analyzed by ramp-hold test for assessing stress relaxation behavior. Both self-assembled and chloroform–cast matrices had similar trends in stress relaxation behavior. However, stress accumulation in self-assembled matrix was half that of chloroform–cast matrix. In vitro cell cultures were conducted using human foreskin fibroblast (HFF-1) in serum-free medium. Cytoskeletal actin staining showed cell adhesion and spreading on all matrices. Cell retention was significantly increased in self-assembled matrix compared to chloroform–cast matrix. Addition of gelatin improved the retention of seeded cells on the surface. In summary, PCL matrices generated using this novel technique show significant promise in biomedical applications.     

In vitro and in vivo response to nanotopographically-modified surfaces of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and polycaprolactone

Colloidal lithography and embossing master are new techniques of producing nanotopography, which have been recently applied to improve tissue response to biomaterials by modifying the surface topography on a nano-scale dimension. A natural polyester (Biopol), 8% 3-hydroxyvalerate-component (D400G) and a conventional biodegradable polycaprolactone (PCL) were studied, both nanostructured and native forms, in vitro and in vivo. Nanopits (100-nm deep, 120-nm diameter) on the D400G surface were produced by the embossing master technique (Nano-D400G), while nanocylinders (160-nm height, 100-nm diameter) on the PCL surface were made by the colloidal lithography technique (Nano-PCL). L929 fibroblasts were seeded on polyesters, and cell proliferation, cytotoxic effect, synthetic and cytokine production were assessed after 72 h and 7 days. Then, under general anesthesia, 3 Sprague-Dawley rats received dorsal subcutaneous implants of nanostructured and native polyesters. At 1, 4 and 12 weeks the animals were pharmacologically euthanized and implants with surrounding tissue studied histologically and histomorphometrically. In vitro results showed significant differences between D400G and PCL in Interleukin-6 production at 72 h. At 7 days, significant (P < 0.05) differences were found in Interleukin-1beta and tumor necrosis factor-alpha release for Nano-PCL when compared to Nano-D400G, and for PCL in comparison with D400G. In vivo results indicated that Nano-D400G implants produced a greater extent of inflammatory tissue than Nano-PCL at 4 weeks. The highest vascular densities were observed for Nano-PCL at 4 and 12 weeks. Chemical and topographical factors seem to be responsible for the different behaviour, and from the obtained results a prevalence of chemistry on in vitro data and nanotopography on soft tissue response in vivo are hypothesized, although more detailed investigations are necessary in this field.     

In vitro and in vivo response to nanotopographically-modified surfaces of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and polycaprolactone

Colloidal lithography and embossing master are new techniques of producing nanotopography, which have been recently applied to improve tissue response to biomaterials by modifying the surface topography on a nano-scale dimension. A natural polyester (Biopol^?), 8% 3-hydroxyvalerate-component (D400G) and a conventional biodegradable polycaprolactone (PCL) were studied, both nanostructured and native forms, in vitro and in vivo. Nanopits (100-nm deep, 120-nm diameter) on the D400G surface were produced by the embossing master technique (Nano-D400G), while nanocylinders (160-nm height, 100-nm diameter) on the PCL surface were made by the colloidal lithography technique (Nano-PCL). L929 fibroblasts were seeded on polyesters, and cell proliferation, cytotoxic effect, synthetic and cytokine production were assessed after 72 h and 7 days. Then, under general anesthesia, 3 Sprague–Dawley rats received dorsal subcutaneous implants of nanostructured and native polyesters. At 1, 4 and 12 weeks the animals were pharmacologically euthanized and implants with surrounding tissue studied histologically and histomorphometrically. In vitro results showed significant differences between D400G and PCL in Interleukin-6 production at 72 h. At 7 days, significant (P < 0.05) differences were found in Interleukin-1 β and tumor necrosis factor-α release for Nano-PCL when compared to Nano-D400G, and for PCL in comparison with D400G. In vivo results indicated that Nano-D400G implants produced a greater extent of inflammatory tissue than Nano-PCL at 4 weeks. The highest vascular densities were observed for Nano-PCL at 4 and 12 weeks. Chemical and topographical factors seem to be responsible for the different behaviour, and from the obtained results a prevalence of chemistry on in vitro data and nanotopography on soft tissue response in vivo are hypothesized, although more detailed investigations are necessary in this field.     

In vitro biocompatibility of titanium oxide for prosthetic devices nanostructured by low pressure metal-organic chemical vapor deposition

Metal-Organic Chemical Vapor Deposition (MOCVD) has recently been proposed to coat orthopedic and dental prostheses with metal nanostructured oxide films through the decomposition of oxygenated compounds (single-source precursors) or the reaction of oxygen-free metal compounds with oxygenating agents. The present study was carried out to assess the in vitro biocompatibility in terms of cell proliferation and activation, of commercially pure Ti (control material: TI/MA) coated with nanostructured TiO2 film by MOCVD (Ti/MOCVD) using osteoblast-like cell cultures (MG-63). Evaluations were performed at 3, 7 and 14 days. Cell proliferation showed a similar trend for Ti/MA and TilMOCVD compared to polystyrene; cell number increased with time from seeding to day 7 (p < 0.005), and then decreased progressively until day 14 (ranging from -14% to -47%). The ALP level and OC production showed no significant differences between Ti/MOCVD and Ti/MA at each experimental time. Significantly higher ALP levels were found in Ti/MA at 3 days and in Ti/MOCVD at 7 and 14 days when compared to the polystyrene group. OC production decreased over time and the highest values were observed at 3 days, when it was significantly higher in the Ti/MA than in the polystyrene group (50%, p < 0.05). CICP synthesis was positively affected by the presence of Ti/MOCVD and was higher in Ti/MOCVD than in the polystyrene group. No significant differences were found between Ti/MOCVD and Ti/MA in terms of IL-6 and TGF-beta1 synthesis at any experimental time. In conclusion, the current findings demonstrate that the nanostructured TiO2 coating positively affects the osteoblast-like cell behavior in terms of cell proliferation and activity, thus confirming its high level of in vitro biocompatibility in accordance with expectations.     

In vitro bioactivity and phase stability of plasma-sprayed nanostructured 3Y-TZP coatings

In this work, plasma-sprayed nanostructured zirconia coatings stabilized with 3 mol.% yttria (3Y-TZP) were deposited on Ti substrates. The microstructure and phase composition of coatings were characterized using scanning electron microscopy and X-ray diffraction. The in vitro bioactivity of coatings was evaluated by examining the formation of bone-like apatite on its surface in simulated body fluid. MG63 cell lines were cultured on the coating to investigate its cytocompatibility. The crystalline phase of the as-sprayed coating was tetragonal zirconia, and no monoclinic zirconia was detected. The size of the grains on the as-sprayed coating surface was less than 100 nm. The apatite could precipitate on the surface of the coating immersed in simulated body fluid for 28 days while no apatite was formed on the surface of 3Y-TZP ceramic control, indicating that the bioactivity of the coating is superior to the ceramic with the same composition. It also revealed that the polished coating whose nanostructural outmost layer was removed was bioinert, implying the significance of the nanosized grains for its bioactivity. MG63 cells could adhere, grow and proliferate well on the coating surface, indicating that the coating had good cytocompatibility. Phase stability of plasma-sprayed 3Y-TZP coating was evaluated under hydrothermal conditions at 134 °C. It revealed that the plasma-sprayed nanostructured zirconia coating was more sensitive to aging than that of zirconia ceramics.     

In vitro characterization and osteoblast responses to nanostructured photocatalytic TiO2 coated surfaces

The aims of the study were to characterize a nanostructured photoactive titanium dioxide (TiO(2)) coating and to compare the cellular response of human osteoblasts before and after ultraviolet (UV) irradiation of the coating. A specific nanostructured TiO(2) powder (Degussa P-25), which consists of approximately 80% anatase and 20% rutile, was spin-coated onto commercially pure titanium discs, and was heat-treated thereafter. After topographical, chemical and photocatalytic property characterizations, human osteoblasts were cultured on the coated discs before and after UV irradiation. Cell morphology was evaluated by scanning electron microscopy (SEM), and cell viability was analysed by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. From the contact angle analysis, the wettability significantly improved after UV irradiation. The cultured cells were flattened with numerous elongated lammellipodia; however, no morphological differences were indicated between -UV and +UV surfaces. The MTT assay analysis showed that -UV surface presented significantly higher viability compared to the +UV surface except for one cell population group at 3h where there were no differences. The nanostructured photoactive TiO(2) surface improved its hydrophilicity by UV irradiation, however no enhancing effect in cell response was confirmed at the time tested compared to the non-irradiated surface.     

Evaluation of mesoporous silicon/polycaprolactone composites as ophthalmic implants

The suitability of porous silicon (pSi) encapsulated in microfibers of the biodegradable polymer polycaprolactone (PCL) for ophthalmic applications was evaluated, using both a cell attachment assay with epithelial cells and an in vivo assessment of biocompatibility in rats. Microfibers of PCL containing encapsulated pSi particles at two different concentrations (6 and 20 wt.%) were fabricated as non-woven fabrics. Given the dependence of Si particle dissolution kinetics on pSi surface chemistry, two different types of pSi particles (hydride-terminated and surface-oxidized) were evaluated for each of the two particle concentrations. Significant attachment of a human lens epithelial cell line (SRA 01/04) to all four types of scaffolds within a 24 h period was observed. Implantation of Si fabric samples beneath the conjunctiva of rat eyes for 8 weeks demonstrated that the composite materials did not cause visible infection or inflammation, and did not erode the ocular surface. We suggest that these novel composite materials hold considerable promise as scaffolds in tissue engineering with controlled release applications.     

In vitro evaluation of random and aligned polycaprolactone/gelatin fibers via electrospinning for bone tissue engineering

Scaffold, as an essential element of tissue engineering, should provide proper chemical and structural cues to direct tissue regeneration. In this study, aligned and random polycaprolactone (PCL)/gelatin fibrous scaffolds with different mass ratio were electrospun. Chemical, structural, and mechanical properties of PCL/gelatin fibrous scaffolds were characterized by FTIR and tensile measurements. The average diameters of different groups were between 334.96?±?41.43?nm and 363.78?±?50.49?nm. Blending PCL with gelatin increased the mechanical properties of the scaffolds. The cell culture results demonstrated that the mass ratio of PCL and gelatin showed no obvious effects on cell behavior, whereas the cell growth behavior was affected by the fibers orientation. Higher elongation ratio, enhanced cell proliferation and elevated alkaline phosphatase activity were observed for cells cultured on aligned fibers. The findings in our research provide insightful information for the design and fabrication of scaffolds for bone tissue engineering.     

In vitro T-cell proliferative response to the flavivirus, west Nile.

West Nile virus (WNV)-specific murine T-cell proliferation in vitro was investigated in terms of conditions that optimize antigen-specific responses and reduce background proliferation. The responder populations consisted of splenocytes from WNV-primed mice enriched for L3T4+ T cells. Ia+ antigen-presenting cells (APC) were derived from splenocytes of WNV-primed or naive mice. Antigen was a lysate prepared from WNV-infected Vero cells at 12 h postinfection. Strong virus-specific proliferative responses were observed when antigen-pulsed APC were cocultured with responders at a 1:1 ratio. Substantial nonspecific proliferation occurred when culture medium supplemented with 5% fetal bovine serum (FBS) was used, whereas with 1% normal mouse serum a higher degree of antigen specificity was evident, although the magnitude of the responses was lower. The best separation between antigen-specific and background proliferation was obtained by using an exogenous source of T-cell growth factors to amplify for 2 days the proliferation of L3T4+ cells triggered by an initial 3 days of culture with antigen-pulsed APC. This investigation has defined optimal conditions for investigating the stimulation of WNV-primed L3T4+ T-cell proliferation in response to the presentation of viral gene products by Ia+ APC. This assay should permit detailed analysis of the efficiency of various APC populations and identification of viral antigens that stimulate the proliferation of Class II MHC-restricted T cells.     

In vitro cytotoxicity of porous silicon microparticles: Effect of the particle concentration,surface chemistry and size

We report here the in vitro cytotoxicity of mesoporous silicon (PSi) microparticles on the Caco-2 cells as a function of particle size fractions (1.2–75 μm), particle concentration (0.2–4 mg ml^?1) and incubation times (3, 11 and 24 h). The particle size (smaller PSi particles showed higher cytotoxicity) and the surface chemistry treatment of the PSi microparticles were considered to be the key factors regarding the toxicity aspects. These effects were significant after the 11 and 24 h exposure times, and were explained by cell–particle interactions involving mitochondrial disruption resulting from ATP depletion and reactive oxygen species production induced by the PSi surface. These events further induced an increase in cell apoptosis and consequent cell damage and cell death in a dose-dependent manner and as a function of the PSi particle size. These effects were, however, less pronounced with thermally oxidized PSi particles. Under the experimental conditions tested and at particle sizes >25 μm, the non-toxic threshold concentration for thermally hydrocarbonized and carbonized PSi particles was <2 mg ml^?1, and for thermally oxidized PSi microparticles was <4 mg ml^?1.     

3D打印聚己内酯/纳米羟基磷灰石复合支架与骨髓间充质干细胞的体外生物相容性

文题释义： 3D打印技术：是通过计算机设计3D模型,按照某一坐标轴切成无限多个剖面,然后层层打印堆叠形成一个实体的立体模型,使用3D打印技术制备的骨组织工程支架能对支架的内部结构和外形进行自由可控的构建,在支架个性化、精确性、机械强度、孔隙调节、空间结构复杂性方面有独特优势。 纳米羟基磷灰石/聚己内酯复合材料：羟基磷灰石是人体和动物骨骼的主要无机成分,具有良好的骨诱导性,纳米羟基磷灰石由于良好的生物相容性和骨整合能力被广泛用作骨缺损的修复材料;聚己内酯是一种已被FDA批准的生物材料,具有良好的机械性能、生物相容性及降解性。两种材料复合物的多孔结构能够为细胞生长、组织再生及血管化提供有利条件。 背景：聚己内酯/纳米羟基磷灰石复合材料是在常用骨组织工程材料基础上结合3D打印技术制备的新型复合支架材料,目前对于该复合材料的体外生物相容性研究较少。 目的：通过体外实验探讨3D打印聚己内酯/纳米羟基磷灰石复合支架材料的细胞相容性。 方法：利用3D打印技术分别制备聚己内酯及聚己内酯/纳米羟基磷灰石复合支架,表征两组材料的微观结构、孔隙率及力学性能。将大鼠骨髓间充质干细胞分别接种于两组支架表面,CCK-8法检测细胞增殖率,扫描电镜和Live/Dead染色观察细胞在支架上的生长情况。 结果与结论：①两组支架均呈三维网状相互连通结构,纤维呈规律有序的排列、相互交错,纤维表面无空隙,纤维间距、直径较为均一;两组支架的孔隙率比较差异无显著性意义(P > 0.05);复合支架的弹性模量高于单纯聚己内酯支架(P < 0.05);②两组支架表面培养1 d的细胞增殖比较差异无显著性意义(P > 0.05),复合支架表面培养4,7 d的细胞增殖快于单纯聚己内酯支架(P < 0.05);③Live/Dead染色结果显示,两组材料均具有良好的细胞相容性,细胞活性较高,同时复合支架上的贴壁细胞更多一些;④扫描电镜显示,细胞在两种材料上生长形态良好,并紧密黏附于支架表面及微孔附近,同时可见分泌的细胞外基质呈丝状包绕于细胞周围;⑤结果表明,3D打印技术制备的聚己内酯/纳米羟基磷灰石复合支架孔隙较丰富,具备良好的力学性能,细胞相容性良好,可作为骨组织工程的支架材料。 ORCID: 0000-0002-7083-6458(胡超然) 中国组织工程研究杂志出版内容重点：生物材料;骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性;组织工程     

一氧化氮在人工晶体植入术后眼内炎症反应中的作用

目的:探讨一氧化氮(NO)在人工晶体植入术后眼内炎症反应中的作用。方法:将新西兰白兔随机分成3组:(1)对照组;(2)L-精氨酸(L-Arg)组;(3)N-硝基-L-精氨酸(L-NNA)组。各组动物均施行晶体囊外摘除术(ECCE)+人工晶体囊袋内植入术(IOL),并于术后0、1、3、7、14、30 d观察术后眼内炎症反应,包括检查角膜水肿和前房渗出、房水细胞计数和分类;同时测定房水NO₂^-/NO₃^-含量。结果:L-Arg组前房渗出、房水细胞总数和NO₂^-/NO₃^-含量均高于对照组;而L-NNA组前房渗出、房水细胞总数和房水NO₂^-/NO₃^-含量均低于对照组。结论:NO在人体晶体植入术后眼内炎症反应中起一定的作用;使用NOS抑制剂可减少NO产生,降低术后眼内炎症反应。     

In vitro fibroblast response to polyurethane organosilicate nanocomposites

The term nanocomposite refers to organic:inorganic composites where one phase, typically the inorganic phase, has dimensions on the nanoscale. Several authors have noted the potential benefit of biomedical application of nanocomposite technology, and have suggested using quaternary ammonium compounds (QAC) as an organic modification to enhance dispersion of nanoparticles within polymer matrices. This study aimed to examine fibroblast responses in vitro to a range of nanocomposites using different organic modifiers. Composite materials were prepared from a polyether urethane (PEU) and various unmodified and organically modified montmorillonite (MMT) nanoparticles. QAC and amino undecanoic acid (AUA) modified-MMT were added to PEU at loadings ranging from approximately 1 to 15 wt %. Composites with organically modified QAC and AUA particles displayed partially exfoliated and intercalated silicate morphology, respectively. Nanocomposites showed increases in ultimate tensile properties for materials with lower QACMMT loadings. However QAC was shown to significantly inhibit cell growth following release from PEU-QACMMT under extraction conditions mimicking those of the physiological environment. Materials containing silicate modified using AUA were cytocompatible. The results of this study suggest that QAC may be unsuitable as organic modifiers for nanoparticles destined for biomedical use. Alternative modifiers based on AUA confer equivalent dispersion and are of low toxicity.     

Mediation of in vivo glucose sensor inflammatory response via nitric oxide release

In vivo glucose sensor nitric oxide (NO) release is a means of mediating the inflammatory response that may cause sensor/tissue interactions and degraded sensor performance. The NO release (NOr) sensors were prepared by doping the outer polymeric membrane coating of previously reported needle-type electrochemical sensors with suitable lipophilic diazeniumdiolate species. The Clarke error grid correlation of sensor glycemia estimates versus blood glucose measured in Sprague-Dawley rats yielded 99.7% of the points for NOr sensors and 96.3% of points for the control within zones A and B (clinically acceptable) on Day 1, with a similar correlation for Day 3. Histological examination of the implant site demonstrated that the inflammatory response was significantly decreased for 100% of the NOr sensors at 24 h. The NOr sensors also showed a reduced run-in time of minutes versus hours for control sensors. NO evolution does increase protein nitration in tissue surrounding the sensor, which may be linked to the suppression of inflammation. This study further emphasizes the importance of NO as an electroactive species that can potentially interfere with glucose (peroxide) detection. The NOr sensor offers a viable option for in vivo glucose sensor development.     

Regulation of inflammatory response of macrophages and induction of regulatory T cells by using retinoic acid-loaded nanostructured lipid carrier

Immunomodulatory function of all-trans retinoic acid (ATRA) has been gathering much attention for the therapy of autoimmune diseases. ATRA is a chemically unstable molecule which requires proper formulation for targeted delivery. Here we examined nanostructured lipid carrier (NLC) for the formulation of ATRA. NLC is a representative nanoparticle formulation especially suited for oral delivery. We established the preparation procedures of ATRA-containing NLC (NLC-RA) which minimizes the degradation of ATRA during the preparation process. NLC-RA thus obtained was taken up by macrophages and induced anti-inflammatory response via suppressing NF-κB signaling as well as via enhancing the production of anti-inflammatory cytokines. Moreover, NLC-RA enhanced differentiation of naïve T cells to regulatory T cells in the co-culture system with dendritic cells. These results suggest that NLC-RA is a promising alternative therapy for the autoimmune diseases especially intestinal bowel disease.

     

In vitro response of tumour cells to non-uniform irradiation

This study examines differences in tumour cellular response using clonogenic cell survival between uniform and non-uniform irradiation. Cells were irradiated with a 6 MV x-ray intensity-modulated beam, in a single large flask (i.e. intercellular communication is possible) or in three small flasks (i.e. intercellular communication is inhibited across the dose gradient). For non-small-cell lung cancer and melanoma cell lines, the dose response over the entire cell culture was significantly different between freely communicating cell cultures and those with inhibited communication across the dose non-uniformity. Communicating cells exhibited poorer survival in the low dose region of the field but improved survival in the high dose region. In general, the response to non-uniform irradiation appeared to 'average out' over the entire cell culture. This was not seen when intercellular communication was inhibited. The results add strength to the body of evidence regarding bystander effects and the inter-dependence of cellular response.     

In vitro preparation and ellipsometric characterization of thin blood plasma clot films on silicon

The wound-healing process around implants differs from that of a normal healing without the inserted material. In this work, the composition of a natural wound surface was mimicked through clotting of a thin human blood plasma film with approximate ellipsometric thickness of 100 nm onto differently pretreated silicon surfaces. Their stability was investigated by incubations in sodium dodecyl sulphate (SDS) solutions. The enzymatic clot degradation was induced through addition of human tissue plasminogen activator (t-PA) to the plasma and the surface protein remnants after the degradation were analyzed with polyclonal antibodies. The results show that the plasma films were not SDS resistant on hydrophilic silicon. However, stability was obtained after preparation on hydrophobic silicon or when albumin or fibrinogen was immobilized to silicon before the plasma incubations. Different surfaces bound different polyclonal antibodies after the clot film degradation. The methods indicate a simple means to improve or reestablish a normal tissue inflammatory response around biomaterials.