Modelling of the Cell Surface

The Cell Surface contains the Cell Receptors which are important for the Cell Communication in the Human Body. The Cell Receptors identify the Cell to the other Communication-Partner; initiate and secure the Communication; and request, filter and process the required Information. This behaviour will be modelled in an artificial Cell Surface which will be used by the artificial Cells and artificial Substances in SANA.

Each receptor is a public- and private-key which is used for the identification of the receptor and for the secure transmission of information. The identification-protocol is defined for the whole system.

The receptors can be deactivated, changed and activated. Thus, the cell/substance-status can be discovered in reading the cell receptors in the cell surface.

Definition Identification-Protocol

One possible identification-protocol:

Docking Cell = A Knows public and private keys	Other Cell = B
A sends public key to B
	B calculates random*public_key and sends this to A
A calculates random*public_key*private_key = random and sends this to B
	B checks if random is correct

The identification-protocol proofs the knowledge of the public- and private-keys from the docking cell A.

Notes: The operator "*" describes a mathematical operation defined by a cryptographic protocol. Furthermore, the workflow of identification can be changed according to the used cryptographic protocol.

Workflow of a Cell/Substance Docking

If a cell or substance docks – A called - to another cell/component of the system – B called - , a two-step process is initiated:

1. A identifies itself to B. Furthermore, in this process the required information is requested. All receptors of A initiate an identification-process like described above. If this identification-process is successful, B knows the type of A and can send the information which is stored in B for a type like A.
2. B identifies itself to A. Furthermore, in this process the required information is requested. This second step is only present if the B requires information from A. All receptors of B initiate an identification-process like described above. If this identification-process is successful, A knows the type of B and can send the information which is stored in A for a type like B.

Note: If a secure communication is required, the transmission can be encrypted using the public-/private-keys. Protocols for this can be found in the literature about Cryptography.

Application of Cell Docking in an artificial Immune System

• Identification of Cell-/Substance-Type
• Information Request
• Encryption of Information
• Present Status of Cell/Substance
• Binding of Substances to a Cell:
  This means that a substance binds permanently to a cell receptor. It can be used e.g. for labelling a cell or a substance. In order to implement this functionality, the convertibility of the receptors is used: the old receptor deactivates or removes and a new receptor which represents the old receptor with the added substance appears.

"Modelling of the Cell Surface" is mentioned on: Artificial Cell | Extracellular Cell Communication