
Adriana Montaño, Ph.D.
Secondary Associate Professor
Department of Pediatrics
Enzyme replacement therapy, gene therapy, and other treatments for mucopolysaccharidosis type IVA or Morquio Disease.
Research Interests
We are working on developing a registry and growth charts for patients with MPS IVA and are in pre-clinical trials for enzyme replacement therapy for patients affected by MPS IVA. We are also developing a bone targeting system for treatment of MPS disorders, substrate reudction therapy for MPSs, and gene therapy for MPS IVA. Other areas of interest are characterization of hyaluronidases, the molecular evolution of glycosaminoglycans and peptidoglycan receptor proteins, and chondroitin sulfate metabolism.
Recent Publications
Biodegradable polyethylene glycol hydrogels for sustained release and enhanced stability of rhGALNS enzyme
Biodegradable polyethylene glycol hydrogels for sustained release and enhanced stability of rhGALNS enzyme
Mucopolysaccharidosis IVA (Morquio A disease) is a genetic disorder caused by deficiency of N-acetylgalactosamine-6-sulfate-sulfatase (GALNS), leading to accumulation of keratan sulfate and chondroitin-6-sulfate in lysosomes. Many patients become wheelchair-dependent as teens, and their life span is 20-30 years. Currently, enzyme replacement therapy (ERT) is the treatment of choice. Although it alleviates some symptoms, replacing GALNS enzyme poses several challenges including very fast clearance from circulation and instability at 37 °C. These constraints affect frequency and cost of enzyme infusion and ability to reach all tissues. In this study, we developed injectable and biodegradable polyethylene glycol (PEG) hydrogels, loaded with recombinant human GALNS (rhGALNS) to improve enzyme stability and bioavailability, and to sustain release. We established the enzyme’s release profile via bulk release experiments and determined diffusivity using fluorescence correlation spectroscopy. We observed that PEG hydrogels preserved enzyme activity during sustained release for 7 days. In the hydrogel, rhGALNS diffused almost four times slower than in buffer. We further confirmed that the enzyme was active when released from the hydrogels, by measuring its uptake in patient fibroblasts. The developed hydrogel delivery device could overcome current limits of rhGALNS replacement and improve quality of life for Morquio A patients. Encapsulated GALNS enzyme in a polyethylene glycol hydrogel improves GALNS stability by preserving its activity, and provides sustained release for a period of at least 7 days.
Association between mucopolysaccharidosis Type VII and hydrops fetalis
Association between mucopolysaccharidosis Type VII and hydrops fetalis
Oral immunotherapy tolerizes mice to enzyme replacement therapy for Morquio A syndrome
Oral immunotherapy tolerizes mice to enzyme replacement therapy for Morquio A syndrome
Immune response to therapeutic enzymes poses a detriment to patient safety and treatment outcome. Enzyme replacement therapy (ERT) is a standard therapeutic option for some types of mucopolysaccharidoses, including Morquio A syndrome caused by N-acetylgalactosamine-6-sulfate sulfatase (GALNS) deficiency. Current protocols tolerize patients using cytotoxic immunosuppressives, which can cause adverse effects. Here we show development of tolerance in Morquio A mice via oral delivery of peptide or GALNS for 10 days prior to ERT. Our results show that using an immunodominant peptide (I10) or the complete GALNS enzyme to orally induce tolerance to GALNS prior to ERT resulted in several improvements to ERT in mice: (a) decreased splenocyte proliferation after in vitro GALNS stimulation, (b) modulation of the cytokine secretion profile, (c) decrease in GALNS-specific IgG or IgE in plasma, (d) decreased GAG storage in liver, and (e) fewer circulating immune complexes in plasma. This model could be extrapolated to other lysosomal storage disorders in which immune response hinders ERT.
Abnormally increased carotid intima media-thickness and elasticity in patients with Morquio A disease
Abnormally increased carotid intima media-thickness and elasticity in patients with Morquio A disease
Cardiovascular disease frequently causes morbidity and mortality in mucopolysaccharidoses (MPS); however, cardiovascular anatomy and dysfunction in MPS IVA (Morquio A disease) is not well described. Consequently, the study aimed to compare carotid artery structure and elasticity of MPS IVA patients with other MPS patients and healthy control subjects, and quantitate frequency of MPS IVA cardiac structural and functional abnormalities.
50 Years Ago in TheJournal ofPediatrics: Vitamin A and Mucopolysaccharidosis: A clinical and biochemical evaluation