Cathepsin C role in inflammatory gastroenterological, renal, rheumatic, and pulmonary disorders.

Cathepsin C (CatC, syn. Dipeptidyl peptidase I) is a lysosomal cysteine proteinase expressed in several tissues including inflammatory cells. This enzyme is important for maintaining multiple cellular functions and for processing immune cell-derived proteases. While mutations in the CatC gene were reported in Papillon-Lefèvre syndrome, a rare autosomal recessive disorder featuring hyperkeratosis and periodontitis, evidence from clinical and preclinical studies points toward pro-inflammatory effects of CatC in various disease processes that are mainly mediated by the activation of neutrophil serine proteinases. Moreover, tumor-promoting effects were ascribed to CatC. The aim of this review is to highlight current knowledge of the CatC as a potential therapeutic target in inflammatory disorders.

Therapeutic targeting of cathepsin C: from pathophysiology to treatment.

Cathepsin C (CatC) is a highly conserved tetrameric lysosomal cysteine dipeptidyl aminopeptidase. The best characterized physiological function of CatC is the activation of pro-inflammatory granule-associated serine proteases. These proteases are synthesized as inactive zymogens containing an N-terminal pro-dipeptide, which maintains the zymogen in its inactive conformation and prevents premature activation, which is potentially toxic to the cell. The activation of serine protease zymogens occurs through cleavage of the N-terminal dipeptide by CatC during cell maturation in the bone marrow. In vivo data suggest that pharmacological inhibition of pro-inflammatory serine proteases would suppress or attenuate deleterious effects mediated by these proteases in inflammatory/auto-immune disorders. The pathological deficiency in CatC is associated with Papillon-Lefèvre syndrome (PLS). The patients however do not present marked immunodeficiency despite the absence of active serine proteases in immune defense cells. Hence, the transitory pharmacological blockade of CatC activity in the precursor cells of the bone marrow may represent an attractive therapeutic strategy to regulate activity of serine proteases in inflammatory and immunologic conditions. A variety of CatC inhibitors have been developed both by pharmaceutical companies and academic investigators, some of which are currently being employed and evaluated in preclinical/clinical trials.

Autophagic dysfunction in patients with Papillon-Lefèvre syndrome is restored by recombinant cathepsin C treatment.

BACKGROUND: Cathepsin C (CatC) is a lysosomal enzyme involved in activation of serine proteases from immune and inflammatory cells. Several loss-of-function mutations in the CatC gene have been shown to be the genetic mark of Papillon-Lefèvre syndrome (PLS), a rare autosomal recessive disease characterized by severe early-onset periodontitis, palmoplantar hyperkeratosis, and increased susceptibility to infections. Deficiencies or dysfunction in other cathepsin family proteins, such as cathepsin B or D, have been associated with autophagic and lysosomal disorders. OBJECTIVES: Here we characterized the basis for autophagic dysfunction in patients with PLS by analyzing skin fibroblasts derived from patients with several mutations in the CatC gene and reduced enzymatic activity. METHODS: Skin fibroblasts were isolated from patients with PLS assessed by using genetic analysis. Authophagic flux dysfunction was evaluated by examining accumulation of p62/SQSTM1 and a bafilomycin assay. Ultrastructural analysis further confirmed abnormal accumulation of autophagic vesicles in mutant cells. A recombinant CatC protein was produced by a baculovirus system in insect cell cultures. RESULTS: Mutant fibroblasts from patients with PLS showed alterations in oxidative/antioxidative status, reduced oxygen consumption, and a marked autophagic dysfunction associated with autophagosome accumulation. These alterations were accompanied by lysosomal permeabilization, cathepsin B release, and NLR family pyrin domain containing 3 (NLRP3) inflammasome activation. Treatment of mutant fibroblasts with recombinant CatC improved cell growth and autophagic flux and partially restored lysosomal permeabilization. CONCLUSIONS: Our data provide a novel molecular mechanism underlying PLS. Impaired autophagy caused by insufficient lysosomal function might represent a new therapeutic target for PLS.

Papillon-Lèfevre syndrome with palmoplantar keratoderma and periodontitis, a rare cause of pyrexia of unknown origin: a case report.

INTRODUCTION: Papillon-Lefèvre Syndrome is a rare autosomal recessive disorder characterized by diffuse, transgradient palmoplantar keratoderma, destructive periodontitis beginning in childhood, premature loss of primary teeth, and frequent cutaneous and systemic pyogenic infections. Pyogenic liver abscess is an uncommon presentation of the disease present in this case. CASE PRESENTATION: A 16-year-old Punjabi, Pakistani boy presented to the outpatient department of a tertiary-care hospital of Lahore with high-grade fever of 2 months duration. He had been treated for a pyogenic liver abscess 2 years back with antibiotics followed by incision and drainage. He had poor orodental hygiene, palmoplantar keratoderma and periodontitis. His parents had history of consanguinity. His brother and two cousins had similar skin lesions and were edentulous. An orthopentogram showed atrophy of the alveolar bone. He was treated with broad-spectrum antibiotics, and antipyretics for systemic infection. Multivitamins, topical steroids, topical keratolytics and emollients were used for his dermatological issues. CONCLUSIONS: Our patient was successfully treated. His fever settled and his skin lesions improved with antibiotics, topical steroids and keratolytics. He was sent home and was asked to return for follow-up on a monthly basis.

Low-dose acitretin in Papillon-Lefèvre syndrome: treatment and 1-year follow-up.

The Papillon-Lefèvre syndrome (PLS) is a rare, autosomal recessive disease that manifests with palmoplantar keratoderma and destructive periodontitis resulting in early onset periodontal breakdown in deciduous and permanent dentition. Management of this condition is difficult. Here we report one 11-year-old consanguineous Muslim boy suffering from PLS. After failing to get any benefit from methotrexate, three cycles of acitretin, each for 2 months, were given 1 month apart. In each cycle, acitretin (25 mg) was given every other day. At the end of the third cycle, treatment was stopped for 4 months to observe the extent of relapse. Thereafter, acitretin (25 mg) was given twice weekly for 4 months and then the patient was followed up for 1 year. Treatment with acitretin resulted in excellent improvement of periodontitis, increase in the alveolar bone height, and periodontal attachment. Improvement remained stable at the end of 1-year follow-up. There was excellent (>75%) improvement in keratoderma at the end of active therapy. Mild worsening of palmoplantar keratoderma was noticed whenever the drug was stopped. It improved when the drug was restarted. Other areas remained stable. At the end of 1-year follow-up, good improvement (50%) in palmoplantar keratoderma was achieved.

Palmoplantar keratoderma with progressive gingivitis and recurrent pyodermas.

Papillon-Lefèvre syndrome (PLS) is a rare inherited palmoplantar keratoderma (PPK) that is associated with progressive gingivitis and recurrent pyodermas. We present a case exhibiting classic features of this autosomal-recessive condition and review the current understanding of its pathophysiology, diagnosis, and treatment. Additionally, a review of pertinent transgredient PPKs is undertaken, with key and distinguishing features of each syndrome highlighted.

Papillon Lefevre Syndrome and footsteps of mycobacterium tuberculosis.

Papillon Lefevre Syndrome ( PLS ) is a very rare genetic syndrome that only less than 500 cases have reported in the world. Patients have a typical cutaneous involvement with hyperkeratosis especially on the soles and palms and early shedding of primary teeth. Internal organs involvement such as liver abscess has been presented as case reports. This is for the first time that a genetically documented PLS with footsteps of mycobacterium tuberculosis in liver and kidney will report.

Haim Munk syndrome: report of two siblings of northern India treated with acitretin.

Haim Munk Syndrome (HMS) is the allelic mutation of exon 6 codon in cathepsin C gene. Here, we present two cases of same family with HMS having all the cardinal features of HMS which includes palmo plantar keratoderma and periodontitis along with arachnodactyly, acroosteolysis, onychogryphosis, and marked osteopenia on hand wrist radiographs. Both the siblings were treated with cotrimoxazole, acetretin and topical keratolytics and followed up over a period of one year, showed remarkable improvement in palmo plantar keratoderma and periodontitis.

Neutrophil elastase, proteinase 3, and cathepsin G as therapeutic targets in human diseases.

Polymorphonuclear neutrophils are the first cells recruited to inflammatory sites and form the earliest line of defense against invading microorganisms. Neutrophil elastase, proteinase 3, and cathepsin G are three hematopoietic serine proteases stored in large quantities in neutrophil cytoplasmic azurophilic granules. They act in combination with reactive oxygen species to help degrade engulfed microorganisms inside phagolysosomes. These proteases are also externalized in an active form during neutrophil activation at inflammatory sites, thus contributing to the regulation of inflammatory and immune responses. As multifunctional proteases, they also play a regulatory role in noninfectious inflammatory diseases. Mutations in the ELA2/ELANE gene, encoding neutrophil elastase, are the cause of human congenital neutropenia. Neutrophil membrane-bound proteinase 3 serves as an autoantigen in Wegener granulomatosis, a systemic autoimmune vasculitis. All three proteases are affected by mutations of the gene (CTSC) encoding dipeptidyl peptidase I, a protease required for activation of their proform before storage in cytoplasmic granules. Mutations of CTSC cause Papillon-Lefèvre syndrome. Because of their roles in host defense and disease, elastase, proteinase 3, and cathepsin G are of interest as potential therapeutic targets. In this review, we describe the physicochemical functions of these proteases, toward a goal of better delineating their role in human diseases and identifying new therapeutic strategies based on the modulation of their bioavailability and activity. We also describe how nonhuman primate experimental models could assist with testing the efficacy of proposed therapeutic strategies.

Papillon-lefevre syndrome with liver abscess.

An 8 year old boy presented with fever of unknown origin in whom the diagnosis of liver abscess was made. He also had palmoplantar keratoderma and premature loss of teeth, consistent with the diagnosis of Papillon Lefevre syndrome.

Papillon-lefevre syndrome with congenital hepatic fibrosis.

Papillon Lefevre syndrome (PLS) is a rare autosomal recessive disorder, which is characterized by palmar-plantar hyperkeratosis, periodontitis, and premature loss of dentition. We report a 16 years old girl with PLS. The patient presented at 08 years of age with complaints of corn on the feet and hands, and failure to thrive. On examination, her upper primarily canines were loose, she had severe periodontitis, eruption of permanent teeth, diffuse eritematous and hyperkeratotic palms and soles that suggested the syndrome. During the follow-up, the patient was diagnosed to have congenital hepatic fibrosis (CHF) when she was 16 years old, while she was being investigated for the etiology of her splenomegaly and pancytopenia. We report a patient with PLS associated with CHF, an association that has not been previously described. Abbreviations-HbsAg: Hepatitis B virus surface antigen, Anti Hbs: Antibody against Hepatitis B surface antigen, Anti Hbc IgM: Antibody against Hepatitis B cor antigen immunglobulin M, Anti dsDNA: Antibody against double stranded deoksiribonucleic acid, Anti HCV: Antibody against Hepatit C virus, Anti HIV: Antibody against human immun deficiency virus, AST: Aspartat amino transferase, ALT: Alanin amino transferase, Gamma-GT: Gamma glutamyl transferase, LDH: Lactate dehydrogenase & MRI: Magnetic resonance imaging.

Aggressive periodontitis associated with Papillon-Lefèvre syndrome: report of a 14-year follow-up.

This case report describes the periodontal management, therapeutic approach, and 14-year follow-up of a patient diagnosed with Papillon-Lefevre syndrome (PLS). A female child, diagnosed with PLS-associated periodontitis at the age of 9 years and 11 months, presented with hyperkeratosis of the palms and soles, as well as generalized aggressive periodontitis. The dental treatment comprised standard periodontal debridement, scaling and root planing, instructions on oral hygiene, restorations, extraction of hopelessly affected teeth and a therapeutic use of antibiotics. The concomitant supportive periodontal therapy and antibiotic coverage could not stop the loss of periodontal attachment and destruction of the alveolar bone. Four years after treatment was initiated, the last remaining teeth were extracted and complete dentures were constructed. The dentures have been periodically replaced and the patient continues to return for follow-up once a year. The combination of intensive periodontal treatment and antibiotic regimen only temporarily delayed periodontal disease progression and did not prevent loss of both primary and permanent teeth. The outcome of this long-term follow-up case report shows that management of PLS-associated periodontitis is further complicated when the patient is first seen in the mixed dentition stage or later. In these situations, the chances of controlling the progression of periodontal breakdown and minimizing tooth loss are greatly reduced.

Papillon Lefevre syndrome.

Papillon Lefèvre syndrome is a rare disease characterized by skin lesions caused by palmar-plantar hyperkeratosis, and severe periodontal destruction involving both the primary and permanent dentitions. It is transmitted as an autosomal recessive condition and consanguinity of parents is evident in about one-third of cases. Pyogenic liver abscess is an increasingly recognized complication. We report a new case of this association and review the current literature.

Papillon-Lefèvre syndrome: a successful outcome.

BACKGROUND: Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive condition manifested clinically by hyperkeratosis of the palms and soles and rapidly progressive periodontitis resulting in loss of deciduous and permanent teeth. This case report describes the clinical periodontal findings and treatment of a 10-year-old male patient with PLS. The patient provided informed consent, and the study was conducted in accordance with the Helsinki Declaration of 1975, as revised in 2000. METHODS: Upon initial presentation, a full periodontal examination was completed. Conventional probing depths, clinical attachment levels (CAL), gingival index (GI), and plaque index (PI) were measured prior to initial therapy, which involved oral hygiene instruction and scaling and root planing. At reevaluation, initial treatment proved unsuccessful, and a surgical approach with concomitant systemic antibiotic therapy was implemented. In addition, the patient's dermatologist treated his palmoplantar keratoderma with systemic retinoids. Subsequently, the patient was placed on a strict 3-month maintenance protocol and was evaluated over a period of 1 year. RESULTS: Initial treatment with mechanical therapy, oral hygiene instruction, frequent recalls, and systemic antibiotics did not yield efficacious results. However, with the addition of surgical treatment, a favorable clinical outcome was obtained. CONCLUSIONS: Numerous treatment regimens for the periodontal disease seen in PLS can be found in the literature. We demonstrate successful treatment of the periodontal disease seen in this condition using mechanical therapy, systemic antibiotics, and surgical modalities; over a period of 1 year, we were able to achieve significant reductions in gingival inflammation and erythema.

Papillon-Lefèvre syndrome treated with acitretin.

A 7-year-old boy born to consanguineous parents had suffered from palmoplantar keratoderma and chronic gingivitis since the age of 3 months. He was diagnosed with Papillon-Lefèvre syndrome. Genetic testing confirmed that he was homozygous with a point mutation in exon 6 of the cathepsin C gene. One year after initiating treatment with acitretin 10 mg oral daily and trimethoprim-sulfamethoxazole, the patient's skin remains almost lesion-free, and he has new teeth that erupted during treatment and are free of periodontal disease.