Maturation of respiratory syncytial virus within HEp-2 cell cytoplasm.

Electron microscopy of HEp-2 cells infected with respiratory syncytial virus (RSV) strain Long revealed the maturation of RSV on an ultrastructural level. The results showed that the virus maturated by two different pathways. In one of them, the virus assembled and matured before reaching the plasma membrane on the internal vesicle membrane within cytoplasm. The mature virus was delivered to the plasma membrane and to the extracellular space most likely by the transport vesicles and exocytosis. In the other pathway, the virus matured on the plasma membrane as described with other members of the family Paramyxoviridae. Using monoclonal antibodies (MoAbs), we localized viral nucleoprotein (NP) and envelope proteins in cytoplasm by immunoelectron microscopy (IEM).

[Biological standardization of the allergenic extract of Ambrosia elatior]. / Bioloska standardizacija alergogenskog ekstrakta Ambrosia elatior.

Allergenic activity of allergen extract Ambrosia elatior (AE) was tested in fifteen volunteers extremely sensitive to the allergen. The research was performed by using the quantitative prick (P) and the intradermal (ID) test. The results were analyzed by the parallel line assay method. Allergenic activity of the specimen was estimated: by the number of the allergen units (AU) in 1 ml of the undiluted specimen according to the results of the P (prick) test; by the number of the allergen units (AU) in 1 ml of the undiluted specimen according to the results of the I. D. test, and by the in vitro standardized method of the RAST inhibition. These preliminary results show that allergen extract Ambrosio elatior has 100,000-130,000 Bu/ml and ca 1000 AU/ml while allergenic activity of the extract measured by the RAST inhibition method has ca 57,000 IU/ml.