Standard Article

Immune Defence, Cell Mediated

Biomolecular Interactions

  1. Martin F. Bachmann1,
  2. Thomas M. Kundig2

Published Online: 15 SEP 2006

DOI: 10.1002/3527600906.mcb.200400147

Reviews in Cell Biology and Molecular Medicine

Reviews in Cell Biology and Molecular Medicine

How to Cite

Bachmann, M. F. and Kundig, T. M. 2006. Immune Defence, Cell Mediated. Reviews in Cell Biology and Molecular Medicine. .

Author Information

  1. 1

    Cytos Biotechnology AG, Zürich-Schlieren, Switzerland

  2. 2

    University of Zürich, Zürich, Switzerland

Publication History

  1. Published Online: 15 SEP 2006


Many cell types make up the arsenal of the immune system and are directly involved in the destruction of invading pathogens. Broadly, two types of cells can be distinguished: firstly, some cells recognize signals that are associated with pathogens, such as tissue damage or patterns found on pathogens but not in the host. These cells belong to the innate immune system and appeared first during evolution. The second type of cells, the lymphocyte, has developed a complex machinery that allows each lymphocyte to express a single and unique receptor with random specificity, the B- and T-cell receptors. Once these receptors recognize a pathogen, the lymphocyte encoding the receptor undergoes clonal expansion and the lymphocyte population differentiates into effector cells, ridding the pathogen. Lymphocytes therefore make up the specific or adaptive immune system. This article discusses how the various cell types protect from infection with pathogens and elucidates some of the complex interactions between the two systems.


  • B cells;
  • T cells;
  • T helper cells (Th cells);
  • Th1 cells;
  • Th2 cells;
  • Cytotoxic T cells (CTLs);
  • Dendritic cells (DCs)