Please note: The website is written in English. 

Columns are written in Dutch: Last column: April 7, 2016.  Relatieve vergankelijkheid

Abstract in English: After all discussions about a Grexit and a Brexit, we in the Netherlands should think about a Nexit (Netherlands out of the EU). Of course we could wait for an Itexit, a Spexit and a Frexit, but why should we wait on the exit of all other members of the EU in order to be able to rule our own country again?

Also an e-book has been written in Dutch as follows:

Xenos: Bioloog tussen mannen, muizen en motoren (Dutch Edition) 
(To be translated as: Xenos: Biologist between men,
mice and motorcycles)

by Nico van Rooijen 
GO TO:  <www.amazon.nl> and search for 

  • Please note: A new website <www.clodronateliposomes.com> is available for ordering of clodronate liposomes and control liposomes containing no clodronate. Please click on ORDER LIPOSOMES in the above MENU of the present site, to go directly to the order page of the new site. 
  • The new website will also show you a list of current projects brought up to date. The present website will show the list of publications brought up to date. 

cartoon of a liposome and a macrophage

Liposomes as a tool to manipulate macrophage function

From an evolutionary point of view, macrophages are ancient cells. They form the core of the natural immune system and did appear long before the cells forming together the complex immune system of the higher vertebrates. As a consequence, during the evolution, they did acquire functions both in natural immune reactions and in the regulation of functions of many non-phagocytic cells. The latter functions are mainly mediated by soluble molecules such as cytokines and chemokines.

Macrophages are also involved in 'homoiostasis' of the body by ingesting and digesting microorganisms or non-self particles and macromolecules. Digestion is in turn mediated by their lysosomal enzymes.

Liposomes are artificially prepared lipid vesicles, consisting of concentric phospholipid bilayers entrapping aqueous compartments. They can be used to encapsulate strongly hydropihilic molecules solved in aqueous solutions, such as clodronate, a non-toxic bisphosphonate, developed for human application. Freely solved clodronate will not cross liposomal or cellular phospholipid membranes. After injection, liposomes, used as Trojan horses in this case, will be ingested and digested by macrophages followed by intracellular release and accumulation of clodronate. At a certain intracellular concentration, clodronate induces apoptosis of the macrophage. By this approach, i.e. by creating an animal with macrophage depleted tissues or organs, functional aspects of macrophages are studied 'in vivo' in many collaborative projects.

Moreover, promising results were obtained by application of clodronate liposomes for suppression of macrophage activity in various models of autoimmune diseases, transplantation, neurological disorders and gene therapy.


Copyright (C) 2006 Dr. Nico van Rooijen - All rights reserved.