Influence of certain chemical stimuli (messenger substances - chemokines) on the movement of cells (cells of the immune system, bacteria, gametes) If the cells move towards the chemical stimulus (the higher concentration of a chemokine), this is called positive chemotaxis, and the opposite is called negative chemotaxis.
A chemotactic agent with a positive influence is called an attracting agent, while one with a negative influence is called a repellent.
Different groups of substances function as chemokines (also known as chemotactics). Known chemokines are:
- Components of the complement system
- Cytokines
- Components of the bacterial cell membrane (e.g. peptidoglycans)
- Leucotrienes
- Amino acids
- Sex pheromones