Choline and CCL22 Are Prognostic Blood Biomarkers for Hermansky-Pudlak Syndrome Pulmonary Fibrosis.

Identifying molecular biomarkers of pulmonary fibrosis (PF) would improve monitoring the disease progression and response to treatment. Hermansky-Pudlak syndrome (HPS) PF is an inherited type of progressive PF with accelerated onset of PF in patients with HPS type 1 (HPS-1). HPSPF could serve as a model to study biomarkers of progressive PF, given that all HPS-1 subjects eventually develop HPSPF.

A murine model lacking Lyst recapitulates Chediak-Higashi syndrome with an earlier-onset neurodegenerative phenotype.

Chediak-Higashi syndrome (CHS) is a rare, autosomal recessive disorder caused by pathogenic variants in the lysosomal trafficking regulator (LYST) gene and characterized by significant immunological and neurological impairment. Current mouse models do not replicate the early-onset neurological symptoms of patients. We develop and characterize a CHS model lacking the Lyst gene (ΔLYST-B6) using CRISPR-Cas9.

Deep Learning Study of Alkaptonuria Spinal Disease Assesses Global and Regional Severity and Detects Occult Treatment Status.

Deep learning (DL) is increasingly used to analyze medical imaging, but is less refined for rare conditions, which require novel pre-processing and analytical approaches. To assess DL in the context of rare diseases, this study focused on alkaptonuria (AKU), a rare disorder that affects the spine and involves other sequelae; treatments include the medication nitisinone. Since assessing x-rays to determine disease severity can be a slow, manual process requiring considerable expertise, this study aimed to determine whether these DL methods could accurately identify overall spine severity at specific regions of the spine and whether patients were receiving nitisinone.

Deep Learning Study of Alkaptonuria Spinal Disease Assesses Global and Regional Severity and Detects Occult Treatment Status.

Deep learning (DL) is increasingly used to analyze medical imaging, but is less refined for rare conditions, which require novel pre-processing and analytical approaches. To assess DL in the context of rare diseases, we focused on alkaptonuria (AKU), a rare disorder that affects the spine and involves other sequelae; treatments include the medication nitisinone. Since assessing X-rays to determine disease severity can be a slow, manual process requiring considerable expertise, we aimed to determine whether our DL methods could accurately identify overall spine severity, severity at specific regions of the spine, and whether DL could detect whether patients were receiving nitisinone.

Insights into the renal pathophysiology in Hermansky-Pudlak syndrome-1 from urinary extracellular vesicle proteomics and a new mouse model.

Hermansky-Pudlak syndrome type 1 (HPS-1) is a rare, autosomal recessive disorder caused by defects in the biogenesis of lysosome-related organelles complex-3 (BLOC-3). Impaired kidney function is among its clinical manifestations. To investigate HPS-1 renal involvement, we employed 1D-gel-LC-MS/MS and compared the protein composition of urinary extracellular vesicles (uEVs) from HPS-1 patients to normal control individuals.

Chedíak-Higashi Syndrome: Hair-to-toe spectrum.

Chedíak-Higashi Syndrome (CHS) is a rare autosomal recessive disorder caused by mutations in the Lysosomal Trafficking Regulator (LYST) gene, leading to defective lysosomal function in immune cells, melanocytes, and neurons. Clinically, CHS is characterized by a spectrum of symptoms, including immunodeficiency, partial oculocutaneous albinism, bleeding tendencies, neurodevelopmental deficits and progressive neurodegenerative symptoms. The severity of CHS correlates with the type of LYST mutation: the classic form, linked to nonsense or frameshift mutations, presents early in childhood with severe immune dysfunction, recurrent infections, and a high risk of hemophagocytic lymphohistiocytosis (HLH), a life-threatening hyperinflammatory state.

Patient-reported outcomes and functional assessments of patients with Alkaptonuria in a 3-year Nitisinone treatment trial.

Alkaptonuria is a rare disorder of tyrosine catabolism caused by deficiency of homogentisate 1,2-dioxygenase that leads to accumulation of homogentisic acid (HGA). Deposition of HGA-derived polymers in connective tissue causes progressive arthropathy of the spine and large joints, cardiac valvular disease, and genitourinary stones beginning in the fourth decade of life. Nitisinone, a potent inhibitor of the upstream enzyme, 4-hydroxyphenylpyruvate dioxygenase, dramatically reduces HGA production.

Efficacy of T-cell assays for the diagnosis of primary defects in cytotoxic lymphocyte exocytosis.

Primary hemophagocytic lymphohistiocytosis (HLH) is a life-threatening disorder associated with autosomal recessive variants in genes required for perforin-mediated lymphocyte cytotoxicity. A rapid diagnosis is crucial for successful treatment. Although defective cytotoxic T lymphocyte (CTL) function causes pathogenesis, quantification of natural killer (NK)-cell exocytosis triggered by K562 target cells currently represents a standard diagnostic procedure for primary HLH.

Chediak-Higashi syndrome.

Purpose Of Review: Chediak-Higashi syndrome is a rare autosomal recessive disorder characterized by congenital immunodeficiency, bleeding diathesis, pyogenic infection, partial oculocutaneous albinism, and progressive neurodegeneration. Treatment is hematopoietic stem cell transplantation or bone marrow transplantation; however, this does not treat the neurologic aspect of the disease. Mutations in the lysosomal trafficking regulator (LYST) gene were identified to be causative of Chediak-Higashi, but despite many analyses, there is little functional information about the LYST protein.

cDNA sequencing increases the molecular diagnostic yield in Chediak-Higashi syndrome.

Chediak-Higashi syndrome (CHS) is rare autosomal recessive disorder caused by bi-allelic variants in the Lysosomal Trafficking Regulator () gene. Diagnosis is established by the detection of pathogenic variants in in combination with clinical evidence of disease. Conventional molecular genetic testing of by genomic DNA (gDNA) Sanger sequencing detects the majority of pathogenic variants, but some remain undetected for several individuals clinically diagnosed with CHS.

Bi-allelic ATG4D variants are associated with a neurodevelopmental disorder characterized by speech and motor impairment.

Autophagy regulates the degradation of damaged organelles and protein aggregates, and is critical for neuronal development, homeostasis, and maintenance, yet few neurodevelopmental disorders have been associated with pathogenic variants in genes encoding autophagy-related proteins. We report three individuals from two unrelated families with a neurodevelopmental disorder characterized by speech and motor impairment, and similar facial characteristics. Rare, conserved, bi-allelic variants were identified in ATG4D, encoding one of four ATG4 cysteine proteases important for autophagosome biogenesis, a hallmark of autophagy.

LYST deficiency impairs autophagic lysosome reformation in neurons and alters lysosome number and size.

Chediak-Higashi syndrome (CHS) is a rare, autosomal recessive disorder caused by biallelic mutations in the lysosomal trafficking regulator (LYST) gene. Even though enlarged lysosomes and/or lysosome-related organelles (LROs) are the typical cellular hallmarks of CHS, they have not been investigated in human neuronal models. Moreover, how and why the loss of LYST function causes a lysosome phenotype in cells has not been elucidated.

Investigating Determinants and Evaluating Deep Learning Training Approaches for Visual Acuity in Foveal Hypoplasia.

Purpose: To describe the relationships between foveal structure and visual function in a cohort of individuals with foveal hypoplasia (FH) and to estimate FH grade and visual acuity using a deep learning classifier.

Design: Retrospective cohort study and experimental study.

Participants: A total of 201 patients with FH were evaluated at the National Eye Institute from 2004 to 2018.