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INTRODUCTION
Batten Disease can be caused by mutations in several different
genes.
Some forms of Batten Disease are caused by mutations in genes
that produce a defective enzyme.
Forms of Batten involving defective enzymes include CLN1, CLN2,
CLN10, and possibly CLN5.
These enzymes function in the interior of the lysosome, a
degradative compartment of the cell.
Enzyme replacement therapy is
available to treat the non-neurological
symptoms of several
lysosomal storage disorders, such
as mucopolysaccharidosis I
(Hurler disease),
mucopolysaccharidosis II (Hunter
disease), mucopolysaccharidosis
VI (Maroteaux-Lamy syndrome),
Fabry’s disease, Gaucher Type I,
and Pompe disease disorders are
primarily diseases that affect
organs outside the brain, such as
liver and spleen, muscle, kidney,
bone and blood vessels.
When lysosomal enzymes are
added to the exterior of cells,
some of the enzyme can be taken
up by the cell, where it reaches the
lysosome and can perform its
normal function, to break down the
abnormal storage material.
Concept Poster
Enzyme
Cell
Storage Material
Lysosome
1
3
2
Several lysosomal storage
disorders for which enzyme
replacement is available do affect
the brain in some individuals.
Enzyme replacement therapy is
being tested for several of these in
clinical trials (such as Hunter and
Hurler syndrome and CLN2).
Enzymes are being delivered
through a catheter placed under
the skin into the cerebrospinal fluid
and connected to a pump. The
pump is surgically inserted under
skin of the flank for lumbar
injection or of the skull for injection
into the brain. The pump is filled
periodically through a fine needle
inserted through the skin and into
a port on the device.
It is unknown whether this form of
therapy will be effective in
lysosomal disorders that affect the
brain. The results of the ongoing
clinical trials will be relevant to
forms of Batten disease caused by
enzyme deficiencies, like infantile
and late infantile Batten disease.