1. ANIMAL CELL CULTURE

2. ANCHORAGE DEPENDENT CELLS
Monolayer
Substrate attachment for growth
Charged substrate
Contact inhibition controls growth
Necessary for cells to spread or divide(mitosis)
Determines the nature of the cell
All vertebrate cells

4. ANCHORAGE INDEPENDENT CELLS
Suspension cells
No substrate attachment for growth
No charged substrate
Density limitation controls growth
Neoplastic in nature
Cancerous cells, tumor cells, etc.

6. CELL ADHESION MOLECULES
Proteins located on cell surface
Involved in binding with other cells or extracellular matrix
Transmembrane receptors
Calcium dependent CAMs
L-CAMs & N-CAMs

7. CALCIUM DEPENDENT CAMs INTEGRINS
Cell to matrix interaction
Signal transduction from the ECM to the cell
 Ligands include fibronectin, vitronectin, collagen, and laminin
immune patrolling, cell migration, and binding to cells by certain viruses
 GPIIbIIIa, an integrin on the surface of blood platelets responsible for attachment to fibrin within a developing blood clot.

8. CADHERINS class of type-1 transmembrane proteins
Homophilic Ca dependent glycoproteins
Cell to cell interaction
Forms adherens junctions for attachment
Polypeptides that undergo many post-translational modifications to become the proteins which mediate cell-cell adhesion and recognition
720–750 amino acids long
over 80 types of cadherins in humans have been identified and sequenced
Behave as both receptors and ligands
responsible for the separation of the different tissue layers, and for cellular migration
Concentrated at intermediate cell junctions
E-Cadherins , N-Cadherins , P-Cadherins

9. CELL SURFACE MODIFICATIONS
N-CAMs and L-CAMs
Transformed cells don’t attach to the substrate
Transformed cells may lack specific CAMs(e.g. L-CAM).
Effect of L-CAMs is suppressed
Effect of N-CAMs is over expressed
Degree of phosphorylation is also changed
The loss of cell-cell recognition, a product of reduced cell-cell adhesion, leads to disorganized growth pattern and the loss of contact inhibition of cell motility and density limitation of cell proliferation.