No abstract available.
Avidin*

Authors performed the immunohistochemical study with avidin biotin-peroxi- dase complex staining on the nail unit of the human fetus for determining the presence of keratin and prekeratin. Seven fetuses, ranging from 12 to 27 weeks in age, were examined. In all cases, the keratin and prekeratin were found in the epidermis of nail units, but not found in stratum corneum and nail plate. Keratin was located predominantly in suprabasal cells whereas prekeratin was located diffusely in the epidermis. Interestingly keratin and prekeratin were found as early as 12 week-old gestational period. There was no significant difference in presence of keratin and prekeratin.
Avidin ; Epidermis ; Fetus ; Humans*

The located culture of cells on patterned surfaces is useful for tissue engineering, biosensor development and fundamental research of cell biology. It is presented here a rapid fabrication method of Biotin-Avidin protein layers micropattern, which is based on soft-lithography technology. The bovine aortic endothelial cells are cultured on the micropatterned surface. It is found that cell location can be controlled on the scale of individual cell by this method.
Animals ; Avidin ; metabolism ; Biotin ; metabolism ; Cattle ; Cells, Cultured ; cytology ; Tissue Engineering

In this experiment, a novel biotin-avidin conjugation probe was synthesized and employed in the detection of reverse-phase protein microarray. Firstly, the proportion of the biotin-avidin conjugation probe was optimized. Then the rat IgG and goat anti-rat IgG system was served as a model to optimize the fabrication conditions of reverse-phase protein microarray, including the non-specific absorption of streptavidin-Cy3 molecules, spotting buffer as well as protein activities. At last, the biotin-avidin conjugation probe was applied to the detection of the reverse-phase protein microarray. The results show that the protein microarray prepared by using BSA spotting buffer could prevent non-specific absorptions of fluorescent molecules and improve the sensitivity, effectively. In addition, compared with traditional biotin-avidin system, the detection limit could be improved four times using the biotin-avidin conjugation probe. In conclusion, the biotin-avidin conjugation probe has its merits of easy synthesis, low price and could be further conjugated with other signal amplification techniques, which is promising to be used in the detection of protein microarray.
Avidin ; chemistry ; Biotin ; chemistry ; DNA Probes ; Immunoglobulin G ; analysis ; immunology ; Protein Array Analysis ; methods

We have studied the distribution of calcium-binding proteins parvalbumin (PV -IR) and calbindin D-28k (CB -IR) immunoacitivity in the mongrel dog olfactory bulb using monoclonal antibodies and the avidin -biotin -immunoperoxidase method. The possible coexistence of both markers was determined by segmental histochemical and immunohistochemical double labelling of the same section. In the olfactory bulb of mongrel dog, PV-IR and CB-IR were mainly located in the external plexiform layer, and a few scattered in the glomerular layer, mitral cell layer, and glanule cell layer in the order of thier existence. In addition, three neuronal types were observed in the glomerular layer and external plexiform layer border. Horizontal cells and vertical cells of Cajal were also observed after both PV-IR and CB-IR labeling. Distict groups of PV-IR and CB-IR, differing in size, shape, dendritic branching pattern, and staining intensity, were distinguished in the all layers of the olfactory bulb. Specific neuronal populations were positive for both PV-IR and CB-IR markes. No cell colocalized both stains in the mongrel dog olfactory bulb. The number of PV-IR were more than abundant in olfactory bulb compared to the CB-IR cells. The PV-IR and CB-IR postitive cell somata were round, oval, spindle and polygonal in shape, and they were unipolar, bipolar and multipolar in type. The diameters of the somata of the PV-IR and CB-IR neurons were 20~40 micro meter, respectively. Also dendrites of the these neurons were densely arrayed in arborization.
Animals ; Antibodies, Monoclonal ; Avidin ; Calbindins* ; Calcium-Binding Proteins ; Coloring Agents ; Dendrites ; Dogs* ; Immunohistochemistry ; Neurons* ; Olfactory Bulb*

BACKGROUND: Numerous cell surface proteins of leukemia cells such as CD33 and CD52 have been identified as diagnostic and therapeutic targets. Thus the profiling of the cell surface proteome and proteins restricted to specific leukemia(s) can provide a way to identify novel targets for leukemia diagnosis and therapy. However, there is a lack of data pertaining to the comprehensive analysis of surface membrane proteins because there are few effective strategies for profiling surface membrane proteomes. METHODS: We report on the application of quantitative proteomic techniques that incorporate affinity-capture and purification on monomeric avidin columns to identify all biotinylated cell surface proteins from leukemia cell lines. RESULTS: An analysis of a subset of biotinylated proteins among the different human leukemia cell lines using matrix-assisted laser desorption ionization and tandem mass spectrometry identified, among others, some widely expressed proteins in leukemia cells, such as CD11a, CD11c, CD18, CD31, CD44, and CD147, as well as a set of proteins identified as chaperone proteins, including HSP90, GRP78, GRP75, HSP70, HSP60 and protein disulfide isomerases. On the basis of their known functional roles, several of these proteins may participate in the progression of leukemogenesis and should be considered as potential markers of leukemia. CONCLUSION: Comprehensive profiling of the leukemia cell surface proteome provides an effective approach for the identification of commonly occurring proteins as well as proteins with restricted expression patterns to a specific cell line.
Avidin ; Cell Line ; Diagnosis ; Humans ; Leukemia* ; Membrane Proteins* ; Membranes ; Protein Disulfide-Isomerases ; Proteome ; Tandem Mass Spectrometry

The following experiment was performed to clarify distributional changes of the Ly1, L3T4, Ly2 positive T cells and IgM positive B cells 1, 4, 8, 12 and 40 weeks after birth. Thymus, spleen and lymph node were removed and immunohistochemical staining such as avidin -biotin -peroxidase complex method was used. The results obtained from above epxperiment were as follows; 1. Ly1 positive T cells were decreased after 8 weeks in the thymus and spleen. these were decreased after 40 weeks in the lymph node. 2. There was no difference L3T4 positive T cells in the thymus, but in the spleen decrease of cell number was shown after 40 weeks. 3. Ly2 postive T cells were decreased after 4 weeks in the thymus, after 40 weeks in the spleen. There was no change of distribution in the lymph node. 4. There was no difference distribution of IgM positive B cells. The results suggest that the age related decrease of the immunity is caused by decrease of cellular immunity related to T cell depletion.
Animals ; Avidin ; B-Lymphocytes ; Cell Count ; Immunity, Cellular ; Immunoglobulin M ; Lymph Nodes* ; Mice* ; Parturition ; Spleen ; T-Lymphocytes ; Thymus Gland

To generate drug delivery vector to locales in the body, genetic engineering and expression techniques have been used to produce antibody avidin fusion proteins. Chicken avidin has been fused to mouse-human chimeric IgG3 immediately after the hinge with a flexible linker (H-Flex-Av) and at the end of CH2 (CH2-Av). Fusion heavy chains were expressed with the expected molecular weight, assembled as H2L2 forms with a co-expressed light chain, and were secreted. The expression level of H- Flex-Av was 1~10 ug/ml/10(8)/24 hrs, but that of C2-Av was a very little (0.08~0.9 ug/ ml/10(8)/24 hrs). The resulting H-Flex-Av and CH2-Av fusion proteins continued to bind antigen dansyl and also bound biotinylated bovine serum albumin; both H-Flex-Av and CH2-Av had shown to retain 3-4 times higher relative affinity than that of CH3-Av in ELISA. Importantly the fact that both avidin fusion proteins had a higher relative affinity suggests that these avidin fusion proteins can be effectively used to deliver biotinylated ligands such as drugs and peptides to a certain locale, such as the brain.
Avidin ; Biotin* ; Brain ; Chickens ; Enzyme-Linked Immunosorbent Assay ; Genetic Engineering ; Immunoglobulin G ; Ligands ; Molecular Weight ; Peptides ; Serum Albumin, Bovine

PURPOSE: For periodontal tissue engineering, it is a primary requisite and a challenge to select the optimum types of cells, properties of scaffold, and growth factor combination to reconstruct a specific tissue in its natural form and with the appropriate function. Owing to fundamental disadvantages associated with using a two-dimensional substrate, several methods of seeding cells into three-dimensional scaffolds have been reported and the authors have asserted its usefulness and effectiveness. In this study, we explore the cell attachment of periodontal ligament fibroblasts on nanohydroxyapatite (n-HA) scaffold using avidin biotin binding system (ABBS). METHODS: Human periodontal ligament fibroblasts were isolated from the health tooth extracted for the purpose of orthodontic procedure. HA nanoparticles were prepared and Ca(NO3)2-4H2O and (OC2H5)3P were selected as precursors of HA sol. The final scaffold was 8 mm in diameter and 3 mm in height disk with porosity value of 81.55%. 1x10(5) periodontal ligament fibroblasts were applied to each scaffold. The cells were seeded into scaffolds by static, agitating and ABBS seeding method. RESULTS: The number of periodontal ligament fibroblasts attached was greater for ABBS seeding method than for static or agitating method (P<0.05). No meaningful difference has been observed among seeding methods with scanning electron microscopy images. However, increased strength of cell attachment of ABBS could be deduced from the high affinity between avidin and biotin (Kd=10(-15) M). CONCLUSIONS: The high-affinity ABBS enhances the ability of periodontal ligament fibroblasts to attach to three-dimensionally constructed n-HA scaffolds.
Avidin ; Biotin ; Cell Adhesion ; Dihydroergotamine ; Fibroblasts ; Humans ; Microscopy, Electron, Scanning ; Nanoparticles ; Periodontal Ligament ; Polymethyl Methacrylate ; Porosity ; Seeds ; Tissue Engineering ; Tooth

PURPOSE: In tissue engineering, it is important that the scaffolds have high affinity with cells for making efficient use of cells. The authors studied the binding affinity of human adipose stem cells(ASCs) to micronized acellular dermal matrix(alloderm) using biotin and avidin linkages. METHODS: Human ASCs were harvested from adipose tissue obtained by abdominoplasty. ASCs(1x10(4), 5x10(4), 1x10(5), 5x10(5), 1x10(6), 5x10(6) cells) were attached to micronized alloderm(1mg) in three groups; 1) control group in which no ASCs and alloderm was treated; 2) serum group in which alloderm was exposed to fetal bovine serum; and 3) biotin group in which biotinylated cells were attached to biotinylated alloderm. The binding affinities were determined 1 day after making ASC-alloderm complexes. The proliferation rates were determined by XTT assays in 4, 7, 14, and 21 days and scanning electron microscopic examination was performed in 7 and 21 days after culture of ASC-alloderm complexes. RESULTS: The binding affinities of the biotin group were significantly increased in all cell concentrations. Maximum binding affinity was observed at 5x10(4)/mg of micronized dermal matrix in biotin group. The viabilities were lowest in biotin group in contrast to binding affinity, but the difference was not significant. SEM showed well attachment of cells to micronized dermal matrix in all groups. CONCLUSION: The use of avidin/biotin facilitated human ASCs attaching to micronized acellular dermal matrix. This attachment would not disturb adipose stem cells viabilities. The present study suggests that avidin/ biotin can be used as making efficient use of cells in adipose tissue engineering.
Abdominoplasty ; Acellular Dermis ; Adipose Tissue ; Avidin ; Biotin ; Collagen ; Electrons ; Humans ; Mesenchymal Stromal Cells ; Stem Cells ; Tissue Engineering