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Following Cell-fate in E. coli After Infection by Phage Lambda
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Following Cell-fate in E. coli After Infection by Phage Lambda

Published on: October 14, 2011

Persistence of bacteriophages in experimentally infected cell cultures

H C Orr1, P G Probst, D C Littlejohn

  • 1Cellular Physiology Branch, Division of Pathology, Bureau of Biologics, Food and Drug Administration, Bethesda, Maryland 20014.

Applied Microbiology
|June 1, 1974
PubMed

Insights

Bacteriophages contaminating cell cultures can persist through vaccine manufacturing processes. This study shows a specific phage survived cell culture maintenance, indicating potential carryover into final vaccine products.

Area of Science:

  • Microbiology
  • Virology
  • Vaccine Manufacturing

Background:

  • Cell cultures are essential for producing viral vaccines.
  • Contamination of cell cultures by bacterial viruses (bacteriophages) is a potential concern.
  • Ensuring the purity and safety of viral vaccines requires understanding potential contaminants.

Purpose of the Study:

  • To investigate the persistence of a specific bacteriophage (φV-1(L)) in cell culture systems.
  • To determine if standard cell culture maintenance procedures can eliminate bacteriophage contamination.
  • To assess the implications of bacteriophage persistence for viral vaccine production.

Main Methods:

  • A bacteriophage, φV-1(L), isolated from a live measles vaccine, was intentionally introduced into cell cultures.
  • Cell cultures were subjected to daily medium changes and trypsinization.
  • Cell lysates were prepared using freezing and thawing methods.

Main Results:

  • The bacteriophage φV-1(L) demonstrated persistence in cell cultures despite daily medium changes.
  • Trypsinization, a common cell culture procedure, did not eliminate the bacteriophage.
  • The bacteriophage remained viable in cell lysates prepared by freezing and thawing.

Conclusions:

  • Bacteriophages can exhibit significant resilience within cell culture environments.
  • Standard cell culture maintenance and processing steps may not effectively remove phage contaminants.
  • Phage contamination in cell cultures poses a risk of carryover into the final viral vaccine product, potentially impacting vaccine safety and efficacy.

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