title: Adherence of staphylococcus aureus to influenza A virus-infected Madin-Darby canine kidney cell cultures.
abstract: Madin-Darby canine kidney cells infected with influenza A virus (strains PR8, FM1, Jap 305, and Tex 1) were tested with nine strains of Staphylococcus aureus and group B Streptococcus type Ic to determine whether mammalian cells become susceptible to bacterial adherence as a result of virus infection. Bacterial adherence to virus-infected cells varied depending on the virus strain and on the strain of bacteria tested. A quantitative radioassay was developed to study the parameters of adherence. Attachment of 3H-labeled S. aureus grown in chemically defined or biologically complex medium to FM1 virus-infected cells was significantly increased (P less than 0.0005) compared with attachment to control cells. Adherence coincided with the appearance of hemadsorption, which is a marker of the presence of virus-induced glycoproteins on the cell surface. Adherence was temperature dependent, increased with a decrease in hydrogen ion concentration, and was not affected by the presence of K+, Mg2+, or Ca2+. Adherence was blocked when 3H-labeled S. aureus was pretreated with trypsin but not when cells were pretreated with neuraminidase.
mesh_terms: D000268:Adhesiveness; D000818:Animals; D001665:Binding Sites; D002478:Cells, Cultured; D004285:Dogs; D009980:Influenza A virus; D007668:Kidney; D009976:Orthomyxoviridae Infections / Q000382:microbiology*; D011863:Radioimmunoassay; D013211:Staphylococcus aureus / Q000502:physiology*; D013696:Temperature; D013997:Time Factors; D014357:Trypsin / Q000494:pharmacology
chemical_list: D014357:Trypsin