Rapid detection of type A influenza viruses with monoclonal antibodies to the M protein (M1) by enzyme-linked immunosorbent assay and time-resolved fluoroimmunoassay

Monoclonal antibodies (MAbs) to the M protein (M1) were used in the development of direct detection systems for type A influenza viruses in clinical specimens. Optimal detection by an enzyme-linked immunosorbent assay was achieved when MAbs were used as capture antibodies and rabbit polyclonal antibodies were used as sandwich antibodies. Detection by the enzyme-linked immunosorbent assay required amplification of the virus. direct detection in clinical specimens (nasopharyngeal aspirates) was accomplished when MAbs recognizing two distinct antigenic sites of M1 were used in a time-resolved fluoroimmunoassay. Type A influenza viruses could be detected equally well in specimens obtained during epidemics of both H3N2 and H1N1 influenza viruses.

M protein (M1) of influenza virus: antigenic analysis and intracellular localization with monoclonal antibodies

A panel of 16 monoclonal antibodies recognizing M protein (M1) of influenza virus was generated. Competition analyses resulted in localization of 14 monoclonal antibodies to three antigenic sites. Three monoclonal antibodies localized to site 1B recognized a peptide synthesized to M1 (residues 220 to 236) with enzyme-linked immunosorbent assay titers equivalent to or greater than that seen with purified M1; therefore, site 1B is located near the C terminus of M1. Sites 2 and 3 localize to the N-terminal half of M1. Antigenic variation of M proteins was seen when the monoclonal antibodies were tested against 14 strains of type A influenza viruses. Several monoclonal antibodies showed specific recognition of A/PR/8/34 and A/USSR/90/77 M proteins and little or no reactivity for all other strains tested. Immunofluorescence analysis with the monoclonal antibodies showed migration of M protein to the nucleus during the replicative cycle and demonstrated association of M protein with actin filaments in the cytoplasm. Use of a vaccinia virus recombinant containing the M-protein gene demonstrated migration of M protein to the nucleus in the absence of synthesis of gene products from other influenza virus RNA segments.

Identification of PR8 M1 protein in influenza virus high-yield reassortants by M1-specific monoclonal antibodies

A panel of monoclonal antibodies to the M1 protein of A/PR8/34 (H1N1) (PR8) influenza A virus was found to distinguish in ELISA high-yielding reassortant viruses derived from reassortment of PR8 and X-31 (H3N2) viruses with recently prevalent field strains of H1N1 or H3N2 subtype. These findings are concordant with results of genotyping that demonstrated the presence of PR8 RNA 7 or M1 protein in high-yield reassortants by RNA or protein PAGE. All high-yield vaccine candidate reassortants Application of the M1 monoclonal antibody panel facilitates the isolation of high-yield vaccine candidate reassortants bearing the PR8 M1 gene, and should aid in epidemiologic strain tracking as well.

Detection of influenza viruses through selective adsorption and detection of the M-protein antigen

A model system has been developed which permits rapid detection of influenza viruses through targeting of the M (membrane or matrix)-protein; a type-specific antigen, in an enzyme-linked immunosorbent assay system. This technique exploits the hydrophobic properties of M-protein; the M-protein is selectively and rapidly adsorbed to polystyrene surfaces even in the presence of a 5000-fold excess of bovine serum albumin. Hyperimmune antiserum prepared to purified M-protein is used as the detecting reagent. All type A influenza viruses could be detected by this technique, type B influenza viruses reacted to a slight extent and Sendai virus (parainfluenza virus, type 1) did not react. Virus could be detected to levels as low as 3 ng. Purification of M-protein and preparation of hyperimmune sera from other related virus groups, such as type B influenza viruses, paramyxoviruses and rhabdoviruses should permit detection of these agents by a similar technique.

Stress: a psychophysiological conception

Physiological and psychological conceptions of stress have evolved independently within their respective fields. An attempt has been made to integrate the salient theoretical features of stress in a definition which accommodates them. The merits of this integration have been outlined. It is believed that the integrated approach will led to interdisciplinary understanding among theoreticians, writers, and researchers and will allow a unified theoretical structure to grow.