Insect Cell Culture Engineering

Goosen, Mattheus F. A. Goosen

• Publisher: CRC Press
• Year: 2020
• Print ISBN: 9780367402419
• eBook ISBN: 9781000148879
• Topic: Physical Sciences
• Subtopic: Entomology

Consolidating and expanding current, fundamental notions of virology and animal cell cultivation, this practical reference examines the development of insect cell culture techniques for the production of recombinant proteins and insect pathogenic viruses.;Resolving on-the-job problems such as sparging cell damage and reduced infectivity cells, Insect Cell Culture Engineering: includes special introductory material as well as background information on insect pathogenic viruses, the molecular biology of baculoviruses and bioreactor design; offers advice on how to save time when deciding which insect cell line, bioreactor and medium to exploit; discusses the preparation of mathematical modelling in animal cell culture; addresses the concerns associated with insect cell immobilization and the use of serum-free culture media; provides insights into the protective effects of polymer additives and insect cell gene expression in pharmaceutical research; and analyzes process scale-up and reactor design.;Bridging the gap between laboratory research and pilot plant scale insect culture/baculovirus technology, Insect Cell Culture Engineering is designed as a reference for biochemical and bioprocess engineers, bioprocess technologists, biochemists, molecular and cell biologists, microbiologists, and upper-level undergraduate and graduate students in these disciplines.

1
Insect Cell Culture Engineering: An Overview

Mattheus F. A. Goosen Queen’s University, Kingston, Ontario, Canada

1.1 Introduction

With the discovery of genetic engineering in the 1970s the capabilities of the biopharmaceutical industry vastly expanded. The main driving force behind this revolution was economics. A company now had the ability to mass produce a high value product at modest cost. This was accelerated, initially, by the production of the first human insulin using the E. coli/ plasmid system. The past ten years, however, has seen a sober reassessment of the capability of genetically modified bacteria to produce commercially valuable proteins. The most crucial factor behind this reevaluation was probably the inability of the host cell to perform many of the posttranslational modifications required for the correct biological functioning of many animal proteins. It now appears that the majority of economically attractive animal proteins will have to be produced on an industrial scale using insect and mammalian cells.

The earlier interest in insect cell cultivation stemmed from the prospect of mass producing viral insecticides as an environmentally sound alternative to chemical pest control. The current excitement about insect cell cultivation, on the other hand, is due to the recent development of baculovirus vectors for high level expression of many foreign genes whose products are correctly processed posttranslationally in the insect host cell. The most visible application of this system is the development of the first candidate vaccine against the AIDS virus, HIV, now in clinical trials.

One of the major advantages of the insect cell/baculovirus expression system over bacterial and mammalian expression systems is the very high expression of recombinant proteins, which are in many cases, anti-genically, immunogenically, and functionally similar to their native counterparts (Table 1). Furthermore, baculoviruses are not pathogenic to vertebrates or plants and do not employ transformed cells (or transforming elements) as in mammalian expression systems. Many of the protein modification, processing and transport systems that occur in higher (eukaryotic) cells are utilized by the insect cell/baculovirus system. These modifications may be essential for the proper biological function of a recombinant protein. Typical product yields normally vary from a low of 1-5 mg/L for human interferon to a high of 600 mg/L for β-galactosidase.

Table 1 Recombinant Protein Expression with Insect Cell/Baculovirus System

Gene	Protein size (MW kD)	Modifications	Expression (mg/L)
Human interferon	17/21	Glycosylated, signal peptide cleaved, secreted	1-5
Chloramphenicol acetyl transferase	27	---	100
β-galactosidase	110	---	600
Simian rotavirus	41	---	50
Human reovirus	14.5	---	1-5
Human interleukin	15.5	Signal peptide cleaved, secreted	10-20
Influenza A	85	---	1-5

Source: M. D. Summers and G. E. Smith. (1985). Genetic engineering of the genome Autographa californica nuclear polyhidrosis virus. Genetically Altered Viruses in the Environment (B. Fields, M. Martin and D. Kamely, eds.), Banbury Rept. 22, Cold Spring Harbor, New York.

Efficient cultivation methods are a key factor in the commercial exploitation of insect cell systems. The culturing conditions for insect and mammalian cells are similar. Most of the culture techniques have evolved through the modification of mammalian cell culture procedures.

The culture systems for animal cells, for example, may be divided into two types, those in which the cells are grown attached to the surface of the culture vessel or some other solid support, and those in which the cells are grown suspended in the liquid medium. The former is usually referred to as substrate- or anchorage-dependent culture and the latter suspension culture. The most promising approach for insect cells involves cultivation in suspension using bioreactor technology that is currently applied successfully to microbial and mammalian cell product manufacturing. There have been reports on suspension cell growth in various types of vessels such as spinner flasks, stirred tanks and airlift bioreactors (Table 2). Aside from su...

Table of contents

• Cover
• Series Page
• Halftitle Page
• Title Page
• Copyright Page
• Series Introduction
• Preface
• Contents
• Contributors
• Original Halftitle
• 1. Insect Cell Culture Engineering: An Overview
• 2. An Overview of the Molecular Biology and Applications of Baculoviruses
• 3. Bioreactor Design for Insect Cell Cultivation: A Review
• 4. Insect Cell Immobilization
• 5. Applications of Insect Cell Gene Expression in Pharmaceutical Research
• 6. Scale-Up Considerations and Bioreactor Development for Animal Cell Cultivation
• 7. Serum-Free Media
• 8. Foreign Gene Expression in Insect Cells
• 9. The Future of Insect Cell Culture Engineering
• Index