Biomedical subjects

Christine Bodemer

Publications and source records attributed to Christine Bodemer.

29 records · Page 2Linked to original sources

PubMed2003

Molecular basis of the spectral expression of CIAS1 mutations associated with phagocytic cell-mediated autoinflammatory disorders CINCA/NOMID, MWS, and FCU.

NALP proteins are recently identified members of the CATERPILLER (CARD, transcription enhancer, R(purine)-binding, pyrin, lots of LRR) family of proteins, thought to function in apoptotic and inflammatory signaling pathways. Mutations in the CIAS1 gene, which encodes a member of the NALP (NACHT-, LRR-, and PYD-containing proteins) family, the cryopyrin/NALP3/PYPAF1 protein, expressed primarily in phagocytic cells, were recently found to be associated with a spectrum of autoinflammatory disorders. These include chronic infantile neurologic cutaneous and articular (CINCA) syndrome (also known as neonatal-onset multisystem inflammatory disease [NOMID]), Muckle-Wells syndrome (MWS), and familial cold urticaria (FCU). We describe herein 7 new mutations in 13 unrelated patients with CINCA syndrome and identify mutational hotspots in CIAS1 on the basis of all mutations described to date. We also provide evidence of genotype/phenotype correlations. A 3-dimensional model of the nucleotide-binding domain (NBD) of cryopyrin suggested that this molecule is structurally and functionally similar to members of the AAA+ protein family of ATPases. According to this model, most of the mutations known to affect residues of the NBD are clustered on one side of this domain in a region predicted to participate in intermolecular contacts, suggesting that this model is likely to be biologically relevant and that defects in nucleotide binding, nucleotide hydrolysis, or protein oligomerization may lead to the functional dysregulation of cryopyrin in the MWS, FCU, and CINCA/NOMID disorders.

Adolescent↗

PubMed2003

LEKTI proteolytic processing in human primary keratinocytes, tissue distribution and defective expression in Netherton syndrome.

SPINK5, encoding the putative multi-domain serine protease inhibitor LEKTI, was recently identified as the defective gene in the severe autosomal recessive ichthyosiform skin condition, Netherton syndrome (NS). Using monoclonal and polyclonal antibodies, we show that LEKTI is a marker of epithelial differentiation, strongly expressed in the granular and uppermost spinous layers of the epidermis, and in differentiated layers of stratified epithelia. LEKTI expression was also demonstrated in normal differentiated human primary keratinocytes (HK) through detection of a 145 kDa full-length protein and a shorter isoform of 125 kDa. Both proteins are N-glycosylated and rapidly processed in a post-endoplasmic reticulum compartment into at least three C-terminal fragments of 42, 65 and 68 kDa, also identified in conditioned media. Processing of the 145 and 125 kDa precursors was prevented in HK by treatment with a furin inhibitor. In addition, in vitro cleavage of the recombinant 145 kDa precursor by furin generated C-terminal fragments of 65 and 68 kDa, further supporting the involvement of furin in LEKTI processing. In contrast, LEKTI precursors and proteolytic fragments were not detected in differentiated HK from NS patients. Defective expression of LEKTI in skin sections was a constant feature in NS patients, whilst an extended reactivity pattern was observed in samples from other keratinizing disorders, demonstrating that loss of LEKTI expression in the epidermis is a diagnostic feature of NS. The identification of novel processed forms of LEKTI provides the basis for future functional and structural studies of fragments with physiological relevance.

Carrier Proteins↗

PubMed2003

Late recurrence of inflammatory first-stage lesions in incontinentia pigmenti: an unusual phenomenon and a fascinating pathologic mechanism.

BACKGROUND: Incontinentia pigmenti (IP) is an X-linked genodermatosis that is manifested by neonatal inflammatory vesicles localized along the lines of Blaschko. These lesions usually clear spontaneously within a few months, leaving hyperpigmentation. Ophthalmologic and neurologic symptoms can be associated with IP. Late recurrences of the first-stage inflammatory lesions after the initial rash are uncommon and have been reported infrequently. The mechanism involved in this phenomenon is unclear. However, the recent identification of NEMO/IKKgamma as the gene responsible for IP sheds new light on its pathophysiologic origins. OBSERVATIONS: We report 5 cases of children who experienced episodes of late reactivation of IP. In all cases, the recurrences occurred on the previously hyperpigmented streaks several months or years after resolution of the initial eruptions. In most cases, the recurrences were preceded by an infectious episode. CONCLUSIONS: These IP recurrences suggest that mutated cells can persist a long time in the epidermis. We theorize that infections trigger the reactivations. The NEMO/IKKgamma gene encodes a protein essential in nuclear factor kappaB activation, which is required for resistance to tumor necrosis factor alpha-induced apoptosis. We discuss the role of a proinflammatory cytokine such as tumor necrosis factor alpha as a triggering factor for the reactivation.

Biopsy, Needle↗

PubMed2003

Clinical study of 40 cases of incontinentia pigmenti.

OBJECTIVE: To analyze the distribution of manifestations in a pediatric cohort and define guidelines for follow-up of incontinentia pigmenti (IP). DESIGN: Retrospective study of 47 children referred to the Department of Pediatric Dermatology with a diagnosis of IP between 1986 and 1999. SETTING: The private or institutional practice of participating dermatologists and pediatricians. MAIN OUTCOME MEASURES: Evaluation of IP clinical diagnosis using the Landy and Donnai criteria. RESULTS: Because hyperpigmentation following the Blaschko lines may be observed in several pigmented disorders, 7 patients were found misdiagnosed. During the neonatal period, erythema, vesicles, and hyperkeratotic le sions were rarely absent in the patients with IP. Ocular and neurological abnormalities were frequent (20% and 30%, respectively) but rarely severe (8% and 7.5%, respectively). CONCLUSIONS: Clinical diagnosis is the first main step for a correct phenotype/genotype correlation, which remains indispensable to better understand the pathological mechanisms of IP and develop new therapies. In doubtful cases, molecular analysis is helpful but characteristic histological features must be added as major criteria for IP diagnosis. Multidisciplinary follow-up is needed, particularly during the first year of life, to detect possible ophthalmologic and neurological complications. Neuroimaging ought to be performed in the case of abnormal neurological examination results or when vascular retinopathy is detected.

Child↗

PubMed2003

Skin expression of metalloproteinases and tissue inhibitor of metalloproteinases in sibling patients with recessive dystrophic epidermolysis and intrafamilial phenotypic variation.

A number of COL7A1 mutations have now been reported in recessive dystrophic epidermolysis bullosa patients, and the analysis of phenotype-genotype correlations showed evidence for interfamilial and intrafamilial phenotypic variability, occurring for the same mutation. Collagenase and stromelysin activities have been found to be overexpressed in skin cultures of some recessive dystrophic epidermolysis bullosa patients, and tissue destruction in the disease process might result from an imbalance of metalloproteinases (MMP) over tissueinhibitor of metalloproteinases (TIMP). So we suspected that the phenotypic variability for the same mutation could be linked to other genetic or environmental factors, as a particular balance between MMP and TIMP. Organ cultures were performed using explants from the skin of three patients from the same family with recessive dystrophic epidermolysis bullosa to reveal and quantify the expression of MMP-1 (collagenase 1), MMP-2 and MMP-9 (gelatinases A and B), MMP-3 (stromelysin 1), TIMP-1, and TIMP-2, and to compare the results with those obtained with two human control skins, with the same experimental conditions. Increased amounts of all metalloproteinases investigated were observed in the skin of the three recessive dystrophic epidermolysis bullosa affected sibling brothers, both in lesioned and in apparently nonlesioned skin, compared with controls. The amounts of MMP-1, MMP-2, MMP-3, and MMP-9 increased particularly in the skin of the more clinically affected patient. Furthermore for this patient we evidenced higher amounts of MMP-1 and also a lower TIMP-1 amount in his unlesioned and lesioned skin compared with the other two affected patients and with healthy control donors. So we can suspect that recessive dystrophic epidermolysis bullosa phenotypic variability could be related to patients' collagenase activity heterogeneity, linked to imbalance between MMP-1 and TIMP-1.

Adolescent↗

PubMed2003

A hypermorphic IkappaBalpha mutation is associated with autosomal dominant anhidrotic ectodermal dysplasia and T cell immunodeficiency.

X-linked anhidrotic ectodermal dysplasia with immunodeficiency (XL-EDA-ID) is caused by hypomorphic mutations in the gene encoding NEMO/IKKgamma, the regulatory subunit of the IkappaB kinase (IKK) complex. IKK normally phosphorylates the IkappaB-inhibitors of NF-kappaB at specific serine residues, thereby promoting their ubiquitination and degradation by the proteasome. This allows NF-kappaB complexes to translocate into the nucleus where they activate their target genes. Here, we describe an autosomal-dominant (AD) form of EDA-ID associated with a heterozygous missense mutation at serine 32 of IkappaBalpha. This mutation is gain-of-function, as it enhances the inhibitory capacity of IkappaBalpha by preventing its phosphorylation and degradation, and results in impaired NF-kappaB activation. The developmental, immunologic, and infectious phenotypes associated with hypomorphic NEMO and hypermorphic IKBA mutations largely overlap and include EDA, impaired cellular responses to ligands of TIR (TLR-ligands, IL-1beta, and IL-18), and TNFR (TNF-alpha, LTalpha1/beta2, and CD154) superfamily members and severe bacterial diseases. However, AD-EDA-ID but not XL-EDA-ID is associated with a severe and unique T cell immunodeficiency. Despite a marked blood lymphocytosis, there are no detectable memory T cells in vivo, and naive T cells do not respond to CD3-TCR activation in vitro. Our report highlights both the diversity of genotypes associated with EDA-ID and the diversity of immunologic phenotypes associated with mutations in different components of the NF-kappaB signaling pathway.

Child↗

PubMed2002

The NF-kappaB signalling pathway in human diseases: from incontinentia pigmenti to ectodermal dysplasias and immune-deficiency syndromes.

The transcription factor NF-kappaB regulates the expression of numerous genes controlling the immune and stress responses, inflammatory reaction, cell adhesion, and protection against apoptosis. Incontinentia pigmenti (IP) is the first genetic disorder to be ascribed to NF-kappaB dysfunction. IP is an X-linked dominant genodermatosis antenatally lethal in males. A complex rearrangement of the NEMO (NF-kappaB essential modulator) gene accounts for 85% of IP patients, and results in undetectable NEMO protein and absent NF-kappaB activation. On the other hand, hypohidrotic/anhidrotic ectodermal dysplasia (HED/EDA) has been ascribed to at least three genes also involved in NF-kappaB activation: ectodysplasin (EDA1), EDA-receptor (EDAR) and EDAR-associated death domain (EDARADD). During hair follicle morphogenesis, EDAR is activated by ectodysplasin, and uses EDARADD as an adapter to build a signal transducing complex that leads to NF-kappaB activation. Hence, several forms of HED/EDA also result from impaired activation of the NF-kappaB cascade. Finally, hypomorphic NEMO mutations have been found to cause anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID), whilst stop codon mutations cause a more severe phenotype associating EDA-ID with osteopetrosis and lymphoedema (OL-EDA-ID). The immunological and infectious features observed in patients result from impaired NF-kappaB signalling, including cellular response to LPS, IL-1beta, IL-18, TNF-alpha, Tlr2 and CD40 ligand. Consistently, mouse knockout models have shown the essential role of NF-kappaB in the immune, inflammatory and apoptotic responses. Unravelling the molecular bases of other forms of EDA not associated with mutations in NEMO will possibly implicate other components of the NF-kappaB signalling pathway.

Animals↗

PubMed2002

Netherton syndrome: disease expression and spectrum of SPINK5 mutations in 21 families.

Netherton syndrome is a severe autosomal recessive skin disorder characterized by congenital erythroderma, a specific hair-shaft abnormality, and atopic manifestations with high IgE levels. Recently, we identified SPINK5, which encodes the serine protease inhibitor Kazal-type 5 protein (LEKTI), as the defective gene in Netherton syndrome. Here we describe the intron-exon organization of the gene and characterize the SPINK5 mutations in patients from 21 families of different geographic origin, using denaturing high performance liquid chromatography and direct sequencing. We identified 18 mutations, of which 13 were novel and seven (39%) were recurrent. The majority of the mutations were clustered between exons 1-8 and exons 21-26. They comprised four nonsense mutations (22%), eight frameshift insertions or deletions (44%), and six splice-site defects (33%). All mutations predict the formation of premature termination codons. Northern blot analysis showed variable reduction of SPINK5 mutant transcript levels, suggesting variable efficiency of nonsense-mediated mRNA decay. Seven patients were homozygotes, eight were compound heterozygotes, and five were heterozygotes with only one identifiable SPINK5 mutation. Five mutations, one of which resulted in perinatal lethal disease in three families, were associated with certain ethnic groups. We also describe 45 intragenic polymorphisms in the patients studied. The clinical features of erythroderma, trichorrhexis invaginata, and atopic manifestations were present in the majority of affected individuals and ichthyosis linearis circumflexa was seen in 12 out of 24 patients. Interfamilial and intrafamilial variation in disease severity was observed, with no clear correlation between mutations and phenotype, suggesting that the degree of severity may be affected by other factors.

Adolescent↗

PubMed2002

Cutaneous EBV-related lymphoproliferative disorder in a 15-year-old boy with AIDS: an unusual clinical presentation.

Lymphomas are a well-known malignancy in individuals with human immunodeficiency virus type 1 (HIV-1) infection. Most lymphomas are of B-cell lineage and cutaneous involvement is rare. Cutaneous T-cell lymphomas have been previously described in adults with HIV-1 infection but are exceptional in HIV-1 infected-children. The authors report here the extremely rare case of a large-cell cutaneous lymphoproliferation of T-cell lineage expressing Epstein-Barr virus (EBV) antigens in a 15-year-old boy with AIDS and his uncommon clinical presentation. The atypical clinical evolution with a nonaggressive treatment emphasizes that for immunosuppressed patients, the diagnosis of immunosuppression-related lymphoproliferative disorder should be considered before giving the diagnosis of malignant lymphoma when tumoral lymphoid cells express EBV antigens.

Acquired Immunodeficiency Syndrome↗

PubMed2002

Osteopetrosis, lymphedema, anhidrotic ectodermal dysplasia, and immunodeficiency in a boy and incontinentia pigmenti in his mother.

A child with X-linked osteopetrosis, lymphedema, anhidrotic ectodermal dysplasia, and immunodeficiency (OL-EDA-ID) was recently reported. We report the clinical features of a second boy with this novel syndrome and his mother, who presented with signs of incontinentia pigmenti (IP). The child had mild osteopetrosis without neurosensory complications, unilateral lymphedema of the left leg, and characteristic features of anhidrotic ectodermal dysplasia with sparse hair, facial dysmorphy, delayed eruption of teeth, and sweat gland abnormalities. He died at 18 months of severe immunodeficiency with multiple infections caused by Gram-negative (Salmonella enteritidis) and Gram-positive (Streptococcus pneumoniae) bacteria, nontuberculous mycobacteria (Mycobacterium kansasii), and fungi (Pneumocystis carinii). His 30-year-old mother's medical history, together with residual cutaneous lesions, was highly suggestive of IP without neurologic impairment. In this patient with OL-EDA-ID, we detected the same NF-kappaB essential modulator stop codon hypomorphic mutation identified in the previous patient. The occurrence of the same clinical features in 2 unrelated patients with the same genotype demonstrates that OL-EDA-ID is a genuine clinical syndrome. The clinical and biological descriptions of the proband and his mother further corroborate the relationship between IP and EDA. Both syndromes are allelic and are associated with mutations in NF-kappaB essential modulator, with a genotype-phenotype correlation in hemizygous males. In contrast, loss-of-function mutations and hypomorphic mutations may cause IP in females.

Abnormalities, Multiple↗

PubMed2002

Severe cardiac involvement in children with systemic sclerosis and myositis.

OBJECTIVE: To assess the outcome of children with systemic sclerosis (SSc) and features of polymyositis. METHODS: The charts of 4 children who met the American College of Rheumatology criteria for SSc and had features of polymyositis, as defined by the presence of proximal muscle weakness and elevated serum creatine phosphokinase or aldolase level, were retrospectively reviewed. RESULTS: All children had multivisceral involvement including (1) myocardial perfusion defects in all cases, with mild to severe dilated cardiomyopathy in 3; (2) lung restrictive syndrome in 3; (3) mild to severe esophageal involvement in all cases; and (4) severe intestinal dysfunction in one child. Combination therapy of corticosteroids, methotrexate (MTX), and cyclosporine resulted in improved skin thickness and muscle strength scores in all cases, as well as in lung restrictive syndrome in 2, but was not effective regarding the progression of intestinal malabsorption in one patient, esophageal dysmotility in 3 patients, and dilated cardiomyopathy in 3. Endstage cardiac failure caused 2 deaths. In one child, heart transplantation was performed for the first time in this indication. CONCLUSION: Children with diffuse cutaneous SSc and features of polymyositis are prone to develop severe cardiomyopathy. Combination therapy of corticosteroids, MTX, and cyclosporine seems to be active on muscle, skin, and lung involvement but does not impair progression of esophageal or myocardial dysfunction. Heart transplantation might be considered, as an experimental treatment, in young patients with severe cardiomyopathy and no other irreversible organ damage.

Adolescent↗