Subject(s)
Bacteria/pathogenicity , Biotechnology/trends , Cells, Cultured/microbiology , MycoplasmaABSTRACT
Gelatin, prepared commercially by degradation of animal collagen, was studied to see whether it had an affinity for fibronectin, which has a known affinity for collagen, and whether gelatin-based drugs could be used to target fibronectin-excreting tumours. Bacillus Calmette-Guérin (BCG) vaccine, an attenuated strain of Mycobacterium bovis, is currently the most effective treatment for superficial transitional cell carcinoma of the bladder. The living cells of the BCG vaccine associate with the fibronectin-bearing surfaces of the tumour. Using a multi-well culture plate technique, gelatin microparticles were shown to be adsorbed onto murine S180 sarcoma cells and this reaction was substantially inhibited by the addition of human plasma fibronectin. The avidities of various BCG substrains and gelatin microparticles for glass-bound fibronectin were measured and the association constants determined. The gelatin microparticles associated with the fibronectin with equal avidity as the BCG cells. The results suggest that this model system may allow the investigation of gelatin-based drug delivery devices capable of targeting fibronectin-bearing surfaces associated with some tumours.
Subject(s)
BCG Vaccine/therapeutic use , Fibronectins/metabolism , Gelatin/metabolism , Sarcoma 180/metabolism , Adsorption , Animals , BCG Vaccine/chemistry , BCG Vaccine/metabolism , Binding Sites , Cattle , Cell Adhesion/physiology , Cell Count , Chromatography, Gas , Drug Delivery Systems , Gelatin/chemistry , Glass , Humans , Mice , Microspheres , Particle Size , Sarcoma 180/ultrastructure , Tumor Cells, CulturedABSTRACT
The presence of additives and large cellular aggregates in freeze-dried BCG vaccines precludes accurate measurement of total cell content by traditional methods. The possibility that extraction and quantitation of a cell membrane fatty acid may provide a suitable means of cell mass determination was tested. The palmitic acid methyl ester peak area determined by gas chromatography was directly proportional to the wet weight of freshly grown Tice-, Pasteur-, and Glaxo-substrain BCG, as well as the dry weight of the ampoule contents after removal of soluble material. Extraction of palmitic acid from Tice BCG vaccine was not appreciably affected by lyophilization and the calculated dry cell mass values of freeze-dried vaccine samples correlated well with particle number. This method, therefore, may be useful in measuring BCG cell mass during all stages of vaccine manufacture and storage.
Subject(s)
BCG Vaccine/analysis , Mycobacterium bovis/cytology , BCG Vaccine/isolation & purification , Cell Membrane/analysis , Chromatography, Gas , Colony Count, Microbial , Fatty Acids/analysis , Freeze Drying , Palmitates/analysisABSTRACT
Three substrains of Mycobacterium bovis BCG which appeared to differ in biological activity could not be differentiated on the basis of fatty acids less than C20, but could be differentiated from six nonpathogenic mycobacterial species.
Subject(s)
Fatty Acids/analysis , Mycobacterium bovis/analysis , Chromatography, Gas , Mycobacterium bovis/classificationSubject(s)
Aluminum/adverse effects , Drug Contamination , Glass , Serum Albumin/administration & dosage , HumansABSTRACT
Two procedures to eliminate virus infectivity from hemoglobin solutions at ambient temperature were evaluated. In the first, virus removal was assessed during the ultrafiltration of hemoglobin solutions through a membrane with a nominal molecular weight cut-off of 100,000 Daltons. The results of this study demonstrated that less than 0.1% of any virus originally spiked into the solution was detectable in the ultrafiltrate. In the second procedure the inactivation of viruses in hemoglobin solutions incubated with tri(n-butyl)phosphate mixed with sodium cholate was studied. Greater than 99% of each of the enveloped viruses tested was inactivated during the first 15 minutes of incubation with greater than 10(5) plaque forming units/ml of each being inactivated after one to six hours. No inactivation of the non-enveloped poliovirus was effected by this treatment. The data imply that both ultrafiltration and detergent/solvent incubation may reduce virus infectivity in hemoglobin solutions, but neither method yields a completely virus free product.
Subject(s)
Cholic Acids , Hemoglobins , Organophosphates , Organophosphorus Compounds , Ultrafiltration , Viruses/isolation & purification , Cholic Acid , Drug Contamination , Herpesvirus 1, Suid/isolation & purification , Herpesvirus 1, Suid/physiology , Molecular Weight , Poliovirus/isolation & purification , Poliovirus/physiology , Sindbis Virus/isolation & purification , Sindbis Virus/physiology , Vesicular stomatitis Indiana virus/isolation & purification , Vesicular stomatitis Indiana virus/physiology , Virus Physiological PhenomenaABSTRACT
When presterilized, closed canister, membrane filter units for sterility testing are validated for process, large volumes of therapeutic products for injection can be tested for sterility, recovered, and added to a subsequent bulk prior to sterile filtration. Intermittent positive pressure, applied to the canisters through the vent filters, makes possible the relatively rapid filtration, with minimal foaming, of viscous solutions such as 25% (w/v) normal serum albumin (human). Canister systems appear to be at least as effective as the standard membrane filter method, and the canisters are particularly suited to the sterility testing of bulks.
