ML II and ML III

I-Cell disorder and Pseudo-Hurler Poldystrophy are forms of a condition known as mucolipidoses. They are also known as ML II and ML III.  Children with ML II/III are missing an enzyme called phosphotransferase.

The two young people in the front of the photo to the right are affected by ML III.  The two children whose pictures appear further down this page are affected by ML II.

The name I-Cell comes from the characteristic appearance of cells under a microscope. One of the first doctors to write about the condition in the 1960's was a Dr. Jules Lerory from Belgium and his name is sometimes used to refer to I-Cell disorder.

ML-III was described by Dr. Maroteaux and Dr. Lamy from France. They called it Pseudo-Hurler Polydystrophy as it resembled a mild form of Hurler Syndrome, one of the mucopolysaccharide disorders. "Polydystrophy" means that many organs are abnormal.

Lipids are complex carbohydrates used in the building of cells in the body. There is a continuous process in the body of replacing used materials and breaking them down for disposal. This activity takes place in a special part of the body's cells called the lysosome. Substances known as enzymes which are responsible for breaking down the used materials can only reach the lysosome after a special signal has been attached to them. In I-Cell disorder and ML III the signal is not attached to them so the enzymes cannot get to the right place and are lost outside the cell.

The incompletely broken down carbohydrates remain stored in cells in the body causing progressive damage. The cells filled with storage material are known as "inclusion cells", hence the name "I-Cell" disorder. In some cases babies may show little sign of the disorder, but as more and more cells become damaged, symptoms start to appear.

The Australian prevalence of ML II and ML III is 1 in 325,000.

At present there is treatment for symptoms as they arise but no cure for the underlying condition. Various experimental methods have been used to try to replace the missing enzyme, but none so far has been of any significant long term benefit.

If you would like to know more about this disease, please order one of our information booklets.

Table of Diseases | Aust MPS Statistics | MPS I | MPS II | MPS III | MPS IV | MPS VI | ML II and ML III