Clinical and molecular study of the extracellular matrix protein 1 gene in a spanish family with lipoid proteinosis

A Rare Case of Lipoid Proteinosis in a Patient Presenting With Seizures: A Case Report and Literature Review

Lipoid proteinosis is a rare genetic disorder affecting the skin, mucous membranes, and central nervous system. Here, we present the case of a 35-year-old female who presented with two episodes of seizures followed by loss of consciousness and injury to the nose. A CT scan and MRI of the brain revealed small symmetrical calcifications in the bilateral medial temporal lobes, a finding highly suggestive of lipoid proteinosis. This case highlights the neurological manifestations of lipoid proteinosis, an extremely rare autosomal recessive disorder, and emphasizes the importance of neuroimaging in its diagnosis.

Identification of a Novel Mutation of Extracellular Matrix Protein 1 Gene in a Chinese Family with Lipoid Proteinosis

Lipoid proteinosis (LP) is a rare autosomal recessive disorder caused by mutations in extracellular matrix protein 1 (ECM1), a glycoprotein expressed in skin. Whole-exome sequencing (WES) was used to investigate two Chinese siblings with suggestive clinical features of LP. They shared one known (c.960G>A) and one novel (c.1081G>T) pathogenic variant in ECM1 gene, inherited from their unaffected parents. The novel mutation (c.1081G>T) led to a termination codon at position 361 and caused nonsense-mediated mRNA decay and lost the function. Our finding expands the genetic etiology spectrum of LP.

Lipoid Proteinosis presenting as beaded papules of the eyelid: report of three cases

Background

Lipoid proteinosis (LP) is a rare multisystem inherited disease. We report here in three LP cases with beaded papules of the eyelid. Their clinical presentations, histological characteristics, and genetic findings are described and discussed.

Case presentation

A 12-year-old boy reported to our hospital with a complaint of ocular irritation, redness, and tearing for two years. He had a history of hoarseness since childhood. His younger brother (5 years old) also complained of hoarseness. Another patient, a 26-year-old woman, described many beaded papules on the edge of her eyelids since age 11 years. She additionally reported hoarseness since 4 years of age. Careful slit-lamp examination in these cases revealed waxy beaded papules on the margins of both eyelids and mild conjunctival congestion. Physical examination showed irregular, rugged scars on their facial skin. Genetic analysis showed the mutation located in exon 6 of the ECM1 gene.

Conclusions

Three LP cases first diagnosed by ophthalmologists are presented. The presence of eyelid papules should prompt the ophthalmologist to pay close attention to the patient’s voice. If there is a definite history of hoarseness, these patients should undergo gene sequence analysis. If necessary, otorhinolaryngology and dermatology consults may help confirm the diagnosis. Treatment is primarily symptomatic to improve patients’ quality of life.

Lipoid proteinosis: A clinical and molecular study in Egyptian patients

Lipoid proteinosis (LP) is an autosomal recessive disorder caused by the loss of function of ECM1 gene. Clinical features include varying degrees of skin thickening, hoarseness of voice and less frequently neuropsychiatric abnormalities. Twelve patients from ten unrelated families with a clinical diagnosis of lipoid proteinosis were enrolled in this study. Extraction of DNA samples of the 12 patients and their parents from peripheral blood by standard methods was performed. Polymerase chain reaction (PCR) amplification of the ECM1 gene was conducted using eight pairs of primers spanning over the 10 exons and splice junctions. Patients exhibited a variety of clinical manifestations with skin affection and hoarseness of voice being the consistent feature. We identified five novel homozygous insertion, small deletion, missense, and splice site mutations as well as two homozygous previously published splice site mutation c.70+1G>C in intron 1 and c.1305-2A>G in intron 8. The specific mutations were: c.10_11insC in exon 1, c.690_691delAG in exon 6, c.734G>A in exon 7, c.1286_1287delAA in exon 8 and c.1393-1G>T in intron 9. The novel mutations c.1393-1G>T and c.10_11insC occurred in three (30%) and two (20%) unrelated patients of the studied families, respectively. Further studies may designate an increased frequency of these mutations among Egyptian LP patients. Identification of pathogenic ECM1 mutations is important for accurate diagnosis and proper genetic counseling.

Genome-Wide Identification and Comparative Analysis of Albumin Family in Vertebrates

Albumins are the most well-known globular proteins, and the most typical representatives are the serum albumins. However, less attention was paid to the albumin family, except for the human and bovine serum albumin. To characterize the features of albumin family, we have mined all the putative albumin proteins from the available genome sequences. The results showed that albumin is widely distributed in vertebrates, but not present in the bacteria and archaea. The phylogenetic analysis of vertebrate albumin family implied an evolutionary relationship between members of serum albumin, α-fetoprotein, vitamin D–binding protein, and afamin. Meanwhile, a new member from the albumin family was found, namely, extracellular matrix protein 1. The structural analysis revealed that the motifs for forming the internal disulfide bonds are highly conserved in the albumin family, despite the low overall sequence identity across the family. The domain arrangement of albumin proteins indicated that most of vertebrate albumins contain 3 characteristic domains, arising from 2 evolutionary patterns. And a significant trend has been observed that the albumin proteins in higher vertebrate species tend to possess more characteristic domains. This study has provided the fundamental information required for achieving a better understanding of the albumin distribution, phylogenetic relationship, characteristic motif, structure, and new insights into the evolutionary pattern.

Production and characterization of domain-specific monoclonal antibodies against human ECM1

Human extracellular matrix protein-1 (hECM1), a secreted glycoprotein, is widely expressed in different tissues and organs. ECM1 has been implicated in multiple biological functions, which are potentially mediated by the interaction of different ECM1 domains with its ligands. However, the exact biological functions of ECM1 have not been elucidated yet, and the functional study of ECM1 has been partially hampered by the lack of sensitive and specific antibodies, especially those targeting different ECM1 domains. In this study, six strains of monoclonal antibody (MAb) against hECM1 were generated using purified, prokaryotically-expressed hECM1 as an immunogen. The MAbs were shown to be highly sensitive and specific, and suitable for western blot, immunoprecipitation assays and immunohistochemistry. Furthermore, the particular ECM1 domains recognized by different MAbs were identified. Lastly, the MAbs were found to have neutralizing activities, inhibiting the proliferation, migration and metastasis of MDA-MB-231 cells. In conclusion, the domain-specific anti-ECM1 MAbs produced in this study should provide a useful tool for investigating ECM1's biological functions, and cellular pathways in which it is involved.

Gastrointestinal involvement in lipoid proteinosis: a ten-year follow-up of a brazilian female patient

Lipoid proteinosis is a rare autosomal recessive disease characterized by the deposition of hyaline material in the skin and internal organs. The main clinical features are hoarseness and typical skin lesions. In this report we describe the endoscopic and radiologic findings in a Brazilian female patient presenting extensive gastrointestinal involvement and the evolution of the detected lesions in ten years of follow-up. Initial upper endoscopy and colonoscopy showed a similar pattern of multiple yellowish nodules throughout the esophagus, stomach, duodenum, and colons. Histological analysis confirmed the diagnosis of lipoid proteinosis. In addition, small bowel follow through demonstrated numerous well defined, round, small filling defects throughout the jejunum. Ten years later, the esophageal lesions remained the same, but none of the previous alterations were detected in the stomach, duodenum, and colons. In conclusion, lipoid proteinosis may affect all gastrointestinal organs with the same pattern of macroscopic and microscopic lesions. Some lesions may regress with increasing age.