Hi5 cells, also known as HighFive or High-Five cells, are a specific type of cell grown in laboratories that have become a valuable tool in scientific research and biotechnology. These cells are widely used for their ability to produce important biological molecules. Their unique properties make them particularly effective for tasks that require large quantities of complex proteins.
What Are Hi5 Cells?
Hi5 cells are a cell line derived from the eggs of the cabbage looper (Trichoplusia ni). A “cell line” refers to cells that have been adapted to grow indefinitely in a laboratory setting. This allows scientists to have a consistent and reliable source of these cells for their experiments and manufacturing processes. The Boyce Thompson Institute for Plant Research developed these cells in the late 1980s.
Their Primary Role in Biotechnology
The main application for Hi5 cells in biotechnology is the production of recombinant proteins. Recombinant proteins are engineered versions of natural proteins, created by introducing genetic instructions into a host cell. These proteins are used in a wide range of applications, including the development of medicines, vaccines, and diagnostic tools, as well as for fundamental research to understand biological processes.
Hi5 cells are particularly effective when used with the Baculovirus Expression Vector System (BEVS). BEVS is a method that utilizes a baculovirus to deliver the genetic blueprint for a desired protein into the Hi5 cells. The infected Hi5 cells produce large quantities of the target recombinant protein. This system allows for the production of complex proteins that are often difficult to make using other methods.
Key Characteristics and Benefits
Hi5 cells possess several characteristics that make them highly advantageous for protein production. They are known for their ability to produce exceptionally high yields of recombinant proteins, often outperforming other insect cell lines like Sf9 or Sf21 by 2 to 10 times. Hi5 cells can be grown in “serum-free media,” which means their culture does not require animal serum, a component that can introduce variability and potential contaminants. This characteristic simplifies purification steps and enhances the safety profile of the produced proteins.
Hi5 cells are also versatile in their growth conditions, capable of being cultured in either an attached state (adherent culture) or freely floating in a liquid medium (suspension culture). These cells also naturally produce microRNAs, small interfering RNAs (siRNAs), and PIWI-interacting RNAs (piRNAs), small molecules involved in regulating gene expression.
Contributions to Science and Medicine
Hi5 cells have significantly contributed to scientific research and medical applications. Their efficiency in producing complex proteins has made them instrumental in developing FDA-approved human vaccines, such as the VLP-based HPV vaccine, Cervarix. Beyond vaccine production, Hi5 cells serve as a valuable research tool. Scientists utilize these cells to study a variety of biological phenomena, investigate disease mechanisms, and develop new therapeutic proteins. The ongoing development of virus-free sub-clones of Hi5 cells further enhances their safety and utility for biopharmaceutical manufacturing.