A CARRIER STATE OF MUMPS VIRUS IN HUMAN CONJUNCTIVA CELLS

Abstract

Mumps virus in a carrier cultures of human conjunctive cells (C-M cultures) persisted through 5 1/2 months of cultivation in medium containing sufficient specific antiserum to keep the fluid free of infectious virus. Cells from C-M cultures were cloned under antiserum with efficiency equal to control, uninfected cultures (40-100%). Of 269 C-M cell clones examined, the cells of 262 contained antigen. Eight infected clones released infectious virus and adsorbed erythrocytes in a manner similar to original C-M cultures. Two uninfected clones were as susceptible to the effects of a cytopathogenic line of mumps virus as were uninfected control cells. In healthy, growing cultures of C-M cells 0.1 to 1.0% of cells adsorbed erythrocytes to their surfaces, suggesting that these cells were releasing virus. Reduction of serum content of the medium to less than 3%, depletion of the medium, or crowding of cultures resulted in hemadsorption by 50 to 90% of cells and an increase of virus in the medium. In growing cultures hemadsorbing cells did not appear damaged. It was observed that cells could simultaneously exhibit hemadsorption and mitosis.