UNIT 2: Cell Culture Techniques and Primary Cell Culture

Exam Focus: The distinction between Primary and Secondary Culture is vital. Focus on the two main methods for isolating cells (mechanical vs. enzymatic disaggregation) and understanding the difference between adherent and suspension cultures.

Table of Contents

1. Cell Culture Techniques
   • Sterilization
   • Isolation of Cells and Tissues
   • Mechanical and Enzyme Disaggregation
   • Primary and Secondary Culture
2. Primary Cell Culture
   • Anchorage Dependent Growth
   • Non-anchorage Dependent Growth
   • Adherent vs. Suspension Culture

1. Cell Culture Techniques

Sterilization

Maintaining an **aseptic environment** is critical. All media, reagents, and equipment must be sterile to prevent contamination by microorganisms.

• **Methods:** **Autoclaving** (for glassware), **Dry Heat**, and **Filtration** (for heat-labile components like serum and certain media) are commonly used.

Isolation of Cells and Tissues

The first step involves obtaining a tissue sample and separating the cells for culturing.

Mechanical and Enzyme Disaggregation

Methods used to separate the tissue into individual cells.

Method	Mechanism	Pros and Cons
Mechanical Disaggregation	Physical disruption (e.g., mincing, forcing tissue through a syringe).	**Pros:** Gentle. **Cons:** Low cell yield.
Enzyme Disaggregation	Use of proteolytic enzymes like **Trypsin** and **Collagenase** to digest the extracellular matrix.	**Pros:** High cell yield, faster. **Cons:** Enzymes can damage cell surface receptors.