Dynamic contrast-enhanced MR imaging in osteoid osteoma: relationships with clinical and CT characteristics.

OBJECTIVE: To correlate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) features to clinical and computed tomography (CT) morphological features of osteoid osteoma (OO). MATERIALS AND METHODS: Our institutional review board approved this retrospective study, waiving the need for informed consent. We included the 102 patients treated with interstitial laser ablation for histologically documented OO at our institution in 2008-2013. DCE-MRI variables were the time-enhancement pattern and rising slope (Sloperise) and CT variables were the bone and segment involved (OObone and OOsegment, respectively), OO location relative to the native cortex (OOcortex), nidus surface area, vessel sign, and largest neighboring-vessel diameter (Dmaxvessel). Descriptive statistics and correlations linking DCE-MRI findings to clinical and CT characteristics were computed. RESULTS: DCE-MRI showed early arterial peak enhancement in 95 (93%) cases, with a mean Sloperise of 9.30 ± 8.10. CT visualized a vessel sign in 84 (82%) cases with a mean Dmaxvessel of 1.10 ± 0.60 mm. By univariate analysis, Sloperise correlated significantly with pain duration and Dmaxvessel (r = 0.30, P = 0.003; and r = 0.22, P = 0.03; respectively). Analysis of variance showed that Sloperise correlated significantly with OObone (P < 0.001), with a steeper slope for OOs located in short or flat bones. CONCLUSION: This study suggests more abundant vascularization of OOs with long-lasting pain and location on short or flat bones.

Molecular characterization of 39 de novo sSMC: contribution to prognosis and genetic counselling, a prospective study.

Small supernumerary marker chromosomes (sSMCs) are structurally abnormal chromosomes that cannot be characterized by karyotype. In many prenatal cases of de novo sSMC, the outcome of pregnancy is difficult to predict because the euchromatin content is unclear. This study aimed to determine the presence or absence of euchromatin material of 39 de novo prenatally ascertained sSMC by array-comparative genomic hybridization (array-CGH) or single nucleotide polymorphism (SNP) array. Cases were prospectively ascertained from the study of 65,000 prenatal samples [0.060%; 95% confidence interval (CI), 0.042-0.082]. Array-CGH showed that 22 markers were derived from non-acrocentric markers (56.4%) and 7 from acrocentic markers (18%). The 10 additional cases remained unidentified (25.6%), but 7 of 10 could be further identified using fluorescence in situ hybridization; 69% of de novo sSMC contained euchromatin material, 95.4% of which for non-acrocentric markers. Some sSMC containing euchromatin had a normal phenotype (31% for non-acrocentric and 75% for acrocentric markers). Statistical differences between normal and abnormal phenotypes were shown for the size of the euchromatin material (more or less than 1 Mb, p = 0.0006) and number of genes (more or less than 10, p = 0.0009). This study is the largest to date and shows the utility of array-CGH or SNP array in the detection and characterization of de novo sSMC in a prenatal context.

[Comparing results of methicillin-resistant Staphylococcus aureus (MRSA) surveillance using the French DRG-based information system (PMSI)]. / État des lieux et évaluation de la surveillance des Staphylococcus aureus résistants à la méticilline (SARM) : PMSI versus surveillance Raisin.

BACKGROUND: The surveillance of methicillin-resistant Staphylococcus aureus (MRSA) is a national priority. The rate of MRSA infections is one of six indicators tracked by the Department of Health. Since 2002, the French institute for public health surveillance (InVS) has monitored MRSA infections to estimate incidence density. Today, the use of the French administrative database (PMSI) could facilitate this surveillance. The aim of this study was to compare MRSA incidence density computed at a national level using PMSI databases with the results from the InVS taken as the reference. METHODS: PMSI databases for the years 2006 to 2009 were used. The reference results were those published by the InVS from 2006 to 2009. MRSA density defined as the number of MRSA infections recorded per year over 1000 hospital stays was computed. It was then compared with the MRSA incidence density measured by InVS. The time course of MRSA incidence in the PMSI records was modeled using a Poisson regression. RESULTS: The incidence density measured by the InVS was higher than the MRSA density computed using the PMSI, but this difference appeared to decrease over time. The PMSI density/InVS MRSA incidence density ratio was 0.8% in 2006 and about 9.2% in 2009. We observed inverted trends with a growing trend in MRSA density identified by the PMSI. Furthermore, the year of study was significantly associated with incidence density (P=0.01). CONCLUSION: Using PMSI data as an additional source of information in the hospital MRSA surveillance process makes it possible to detect and analyze patient repeats at the regional and national levels with linkage facilities. Estimation of incidence density for hospitals not participating to this surveillance system will be the next step.

Filaggrin - revisited.

Profilaggrin (proFLG) and its processing products are critical to the health and appearance of skin. The recent identification of loss-of-function filaggrin (FLG) mutations as a predisposing factor in ichthyosis vulgaris and atopic dermatitis has lead to a resurgent interest in this enigmatic protein. Here, we review the literature on the structure and many functions of proFLG, from its role as a filament-aggregating protein and a source of natural moisturizing factor (NMF), to the more recent discoveries of its role in epidermal barrier formation and its more speculative functions as an antimicrobial and sunscreen. Finally, we discuss the relationship of proFLG with dry skin, the influence of moisturizers on NMF generation and speculate on next generation of FLG research.

Qualitative and quantitative analysis of the binding of GII.4 norovirus variants onto human blood group antigens.

Noroviruses (NoVs) are one of the leading causes of gastroenteritis in children and adults. For the last 2 decades, genogroup II genotype 4 (GII.4) NoVs have been circulating worldwide. GII.4 NoVs can be divided into variants, and since 2002 they have circulated in the population before being replaced every 2 or 3 years, which raises questions about the role of their histo-blood group antigen (HBGA) ligands in their evolution. To shed light on these questions, we performed an analysis of the interaction between representative GII.4 variants and HBGAs, and we determined the role of selected amino acids in the binding profiles. By mutagenesis, we showed that there was a strict structural requirement for the amino acids, directly implicated in interactions with HBGAs. However, the ablation of the threonine residue at position 395 (ΔT395), an epidemiological feature of the post-2002 variants, was not deleterious to the binding of the virus-like particle (VLP) to the H antigen, while binding to A and B antigens was severely hampered. Nevertheless, the ΔT395 VLPs gained the capacity to bind to the Lewis x and sialyl-Lewis x antigens in comparison with the wild-type VLP, demonstrating that amino acid residues outside the HBGA binding site can modify the binding properties of NoVs. We also analyzed the attachment of baculovirus-expressed VLPs from six variants (Bristol, US95/96, Hunter, Yerseke, Den Haag, and Osaka) that were isolated from 1987 to 2007 to phenotyped saliva samples and synthetic HBGAs. We showed that the six variants could all attach to saliva of secretors irrespective of the ABO phenotype and to oligosaccharides characteristic of the secretor phenotype. Interestingly, Den Haag and Osaka variants additionally bound to carbohydrates present in the saliva of Lewis-positive nonsecretors. The carbohydrate binding profile and the genetic and mutagenesis analysis suggested that GII.4 binding to Lewis x and sialyl-Lewis x antigens might be a by-product of the genetic variation of the amino acids located in the vicinity of the binding site. Analysis of the binding properties for the six variants by surface plasmon resonance showed that only post-2002 variants (i.e., Hunter, Yerseke, Den Haag, and Osaka) presented strong binding to A and B antigens, suggesting that the GII.4 evolution could be related to an increased affinity for HBGAs for the post-2002 variants. The combination of increased affinity for ABH antigens and of a newly acquired ability to recognize glycans from Lewis-positive nonsecretors could have contributed to the epidemiological importance of strains such as the Den Haag GII.4 subtype.

Epidemiology and clinical features of gastroenteritis in hospitalised children: prospective survey during a 2-year period in a Parisian hospital, France.

Rotavirus is recognised as the most important agent of severe acute gastroenteritis (AGE) in young children. In a 2-year prospective survey, we investigated the epidemiology and clinical features of the viral and bacterial pathogens in children hospitalised for AGE. The study was performed in a Parisian teaching hospital from November 2001 to May 2004. Clinical data were prospectively collected to assess the gastroenteritis severity (20-point Vesikari severity score, the need for intravenous rehydration, duration of hospitalisation). Stools were systematically tested for group A rotavirus, norovirus, astrovirus and adenovirus 40/41, sapovirus and Aichi virus and enteropathogenic bacteria. A total of 457 children (mean age 15.9 months) were enrolled. Viruses were detected in 305 cases (66.7%) and bacteria in 31 cases (6.8%). Rotaviruses were the most frequent pathogen (48.8%), followed by noroviruses (8.3%) and adenoviruses, astroviruses, Aichi viruses and sapoviruses in 3.5%, 1.5%, 0.9% and 0.4%, respectively. Cases of rotavirus gastroenteritis were significantly more severe than those of norovirus with respect to the Vesikari score, duration of hospitalisation and the need for intravenous rehydration. Rotaviruses were the most frequent and most severe cause in children hospitalised for AGE, and noroviruses also account for a large number of cases in this population.

Age-associated aggravation of clinical disease after primary metapneumovirus infection of BALB/c mice.

Human metapneumovirus (hMPV) is associated with respiratory tract infections among children and adults. Because hMPV induces significant morbidity and mortality in the elderly, a model of hMPV infection in aged BALB/c mice was established. Young (8 weeks old) and aged (18 months old) mice were intranasally inoculated with hMPV. The infected mice showed respiratory dysfunction, as measured by plethysmography, a marked loss in weight (up to 24%), and severe histopathological abnormalities including bronchiolitis obliterans organizing pneumonia. However, clinical severity was far higher in the aged mice, and none of the young infected mice died. Although virus replication in the lung was greater in the older mice, clearance of virus was not delayed compared to young mice. Production of virus-specific antibody as well as neutralizing antibody was lower. Gamma interferon and monocyte chemotactic protein-1 levels in bronchoalveolar lavage fluid were significantly lower in older mice, whereas interleukin-6 and interleukin-4 levels were significantly higher. We observed by flow cytometry a significant increase in the CD4(+) T lymphocytes (P<0.05) of the aged mice and no difference in CD8(+) T-cell recruitment to the respiratory tract between the two groups. The present study investigated the effects of aging on the immunopathogenesis of hMPV infection and suggests that CD4(+) T lymphocytes, the cytokine response, or a defect in humoral response may be associated with the increased disease severity observed in the aged mice.

Evidence of the co-circulation of enteric viruses in sewage and in the population of Greater Cairo.

AIMS: To characterize major enteric viruses (enterovirus, rotavirus, norovirus, astrovirus and adenovirus) in the sewage of Greater Cairo and to compare the results with clinical data collected during the same period. METHODS AND RESULTS: Seventy-two sewage samples from two waste water treatment plants were collected from April 2006 through February 2007. Enteroviruses, noroviruses (NoVs) and rotaviruses (RVs) were detected by RT-PCR in 22%, 18% and 8.3% of the samples, respectively. No adenovirus and astrovirus was detected. G2P[8], G9P[8], G1P[8], G2P[4] and rare G12 RV isolates were detected in the environment as well as a bovine RV. The environmental NoV strains mostly belonged to genogroup I (84%). Rotaviruses and some of the NoVs were similar to those found in the clinical samples at the same time. CONCLUSIONS: The comparison of environmental and clinical data suggests that similar RV and NoV isolates were circulating in the environment and in the population during the same period. SIGNIFICANCE AND IMPACT OF THE STUDY: Few studies have investigated the prevalence and the epidemiology of RVs and NoVs in Cairo. This work is the first to establish a correlation between viral gastroenteritis and the concomitant presence of enteric viruses in the environment for Greater Cairo where combined environmental and clinical surveys should help to prevent infections caused by these major pathogens.

Staphylococcus aureus nasal decolonization before cardiac and orthopaedic surgeries: first descriptive survey in France.

The objective was to describe French hospital nasal screening and decolonization procedures before clean surgery procedures. Information for participants was sent to the French Society for Infection Control members in June 2018. Seventy hospitals participated in the survey; 40% (N = 28) declared having institutional decolonization procedures: 64% (N = 18) in orthopaedic and 56% (N = 15) in cardiac surgeries. All hospitals used mupirocin for nasal decolonization and body decolonization with chlorhexidine (N = 16) or povidone iodine (N = 10). This study is the first to be performed in France giving information in this field. Screening/decolonization procedures are heterogeneous and the evaluation of their clinical impact remains complex.

Evaluation of the Spot Vision Screener in comparison with the orthoptic examination in visual screening in 3-5 year-old schoolchildren.

PURPOSE: To evaluate the Spot Vision Screener (SVS) compared with the orthoptic examination for detection of amblyopia risk factors in preschools. METHODS: This prospective study included children with a visual screening organized by the department of "le" (PMI) in Côte d'Or (Burgundy, France), between June 2017 and April 2018. All children were evaluated with the SVS followed by a clinical orthoptic examination. Results with the SVS were compared with those obtained by clinical orthoptic examination. RESULTS: A total of 1236 subjects were included in the study from 100 preschools. The mean age of the children was 3.6±0.7 years, and 627 were female (50.7%). The orthoptic examination detected 308 (24.9%) children with subnormal visual acuity for age in one eye or both. In children with a history of prematurity, the orthoptic examination was more frequently abnormal (P=0.002), which was not seen with the SVS (P=0.050). The SVS screened 20 (1.6%) children with strabismus, while 40 (3.2%) were detected by orthoptic examination. At the end of the screening, the SVS detected 182 (14.7%) suspect patients while 311 (25.1%) suspect patients were detected after the orthoptic examination. Comparing SVS with orthoptic examination, agreement was fair (κ=0.4). CONCLUSION: The SVS can be a useful device for visual screening, but agreement with the orthoptic examination was only fair. The Spot vision screener should be used in conjunction with a clinical orthoptic examination.

Clinical management of adolescents and young adults suffering from sarcoma in the French Rhône-Alpes region: A prospective exhaustive cohort with 10 years follow up.

INTRODUCTION: Survival of adolescents and young adults (AYA) with sarcoma is lower than in younger patients. The objective of this study was to describe the regional healthcare circuits, the differences in the management between adult, paediatric and mixed units and to assess the prognostic impact of compliance with clinical practice guidelines (CPGs) on overall survival (OS) and on relapse free survival (RFS). MATERIALS AND METHODS: Retrospective analysis of the management and long term follow-up of all 13-25 year old patients with a sarcoma diagnosed in the Rhône-Alpes area between 2000 and 2005. RESULTS: 140 patients satisfied inclusion criteria and were selected. The majority of 13-25 year old patients were treated in paediatric units. Joint management resulted in a higher rate of discussion in multidisciplinary tumour board, inclusion in clinical trials, and fertility preservation. Non-compliance with guidelines was observed in 65% of cases. Overall compliance was not reported to correlate to survival. Compliance of radiotherapy with CPG's seemed associated with a better prognosis for OS (HR = 0.20, 95% CI = [0.10-0.40]; p < 0.0001) and RFS (HR = 0.18, 95% CI = [0.09-0.37; p < 0.0001) as well as compliance of surgery for OS (HR = 0.43, 95% CI = [0.23-0.81]; p = 0.01). Multivariate Cox regression analysis revealed other independent predictors of OS like age at diagnosis, stage and histological subtype. CONCLUSIONS: Management of AYA in joint units seems to improve the quality of care. Compliance of surgery and radiotherapy with CGP's seems to improve survival.

Ubinuclein, a novel nuclear protein interacting with cellular and viral transcription factors.

The major target tissues for Epstein-Barr virus (EBV) infection are B lymphocytes and epithelial cells of the oropharyngeal zone. The product of the EBV BZLF1 early gene, EB1, a member of the basic leucine-zipper family of transcription factors, interacts with both viral and cellular promoters and transcription factors, modulating the reactivation of latent EBV infection. Here, we characterize a novel cellular protein interacting with the basic domains of EB1 and c-Jun, and competing of their binding to the AP1 consensus site. The transcript is present in a wide variety of human adult, fetal, and tumor tissues, and the protein is detected in the nuclei throughout the human epidermis and as either grainy or punctuate nuclear staining in the cultured keratinocytes. The overexpression of tagged cDNA constructs in keratinocytes revealed that the NH(2) terminus is essential for the nuclear localization, while the central domain is responsible for the interaction with EB1 and for the phenotype of transfected keratinocytes similar to terminal differentiation. The gene was identified in tail-to-tail orientation with the periplakin gene (PPL) in human chromosome 16p13.3 and in a syntenic region in mouse chromosome 16. We designated this novel ubiquitously expressed nuclear protein as ubinuclein and the corresponding gene as UBN1.

Trends of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae-producing extended-spectrum beta-lactamase (ESBLE) in eastern France: a three-year multi-centre incidence study.

The objective of this study was to describe trends for the years 2004 to 2006 in the incidence of methicillin-resistant Staphylococcus aureus (MRSA) and Enterobacteriaceae-producing extended-spectrum beta-lactamase (ESBLE) in a large hospital network (70 hospitals in eastern France). The incidence of MRSA per 1,000 patient-days decreased significantly from 0.55 in 2004 to 0.45 in 2006. This trend was observed in medicine and surgery units, whereas MRSA incidence was stable in intensive care, paediatric and obstetric units. The incidence of blood cultures positive for MRSA remained stable at 0.04 per 1,000 patient-days. Conversely, the incidence of ESBLE increased significantly from 0.04 in 2004 to 0.08 in 2006. This increase was caused by the spread of ESBLE-producing Escherichia coli. The mean consumption of alcohol-based gel and solution (ABS), expressed in litres per 1,000 patient-days, was 3.3 in 2002, 4.5 in 2003, 5.4 in 2004 and 6.4 in 2005. There was no association between the consumption of ABS and MRSA incidence. These findings suggest that the French recommendations for the control of multi-drug-resistant bacteria (MDRB) have been effective in reducing, or at least stabilising, the incidence of MRSA in an international context of general increase. However, the diffusion of ESBLE-producing E. coli is a matter of concern and should be carefully monitored.

Reduced fungal contamination of the indoor environment with the Plasmair system (Airinspace).

Aspergillus spp. and other moulds cause life-threatening opportunistic infections in immunocompromised patients. Indoor contamination and construction work that liberate fungal spores are a major source of nosocomial aspergillosis. Dijon hospital is a tertiary care institution in northeast France undergoing construction work beside high-risk clinical units. To determine the impact of this activity, a surveillance programme was implemented one year before building work began in order to establish baseline levels of contamination. Air and surface fungal contamination in adult and paediatric haematology units were prospectively examined following use, or not, of a new air-treatment system with mobile Plasmair units (Airinspace). There were significant reductions in overall fungal contamination for the Plasmair treated rooms for air and surface samples in both clinical units. Plasmair treatment also significantly reduced A. fumigatus in the air. These data suggest that Plasmair units may provide an efficient method of reducing indoor fungal contamination in hospitals.

Prospective survey of indoor fungal contamination in hospital during a period of building construction.

An 18-month survey of indoor fungal contamination was conducted in one haematology unit during a period of construction work. Air was sampled with a portable Air System Impactor and surfaces with contact Sabouraud plates. During this survey the mean concentration of viable fungi in air was 4.2 cfu/m(3) and that for surfaces was 1.7 cfu/plate. At the beginning of construction work, there were increases in airborne fungal spores (from 3.0 to 9.8 cfu/m(3)) in the unit, but concentrations did not exceed 10 cfu/m(3) during the 18-month period. The most frequently recovered airborne fungi were Penicillium spp. (27-38%), Aspergillus spp. (25%) and Bjerkandera adusta, a basidiomycete identified with molecular tools (7-12%). Blastomycetes accounted for more than 50% of the fungal flora on surfaces. Investigating the impact of a new air-treatment system (mobile Plasmair units), there were significant reductions in fungal contamination for the Plasmer -treated rooms, and in these rooms we observed the same level of fungal load whether construction work was in progress or not.

[French recommendations on control measures to reduce the infectious risk in immunocompromised patients]. / Quelles mesures pour maîtriser le risque infectieux chez les patients immunodéprimés ? Recommandations formalisées d'experts.

The increase use of immunosuppressive treatments in patients with solid cancer and/or inflammatory diseases requires revisiting our practices for the prevention of infectious risk in the care setting. A review of the literature by a multidisciplinary working group at the beginning of 2014 wished to answer the following 4 questions to improve healthcare immunocompromised patients: (I) How can we define immunocompromised patients with high, intermediate and low infectious risk, (II) which air treatment should be recommended for this specific population? (III) What additional precautions should be recommended for immunocompromised patients at risk for infection? (IV) Which global environmental control should be recommended? Based on data from the literature and using the GRADE method, we propose 15 recommendations that could help to reduce the risk of infection in these exposed populations.

Clinical severity and molecular characteristics of circulating and emerging rotaviruses in young children attending hospital emergency departments in France.

Group A rotavirus (RVA) is the leading cause of acute gastroenteritis in young children worldwide. A prospective surveillance network has been set up to investigate the virological and clinical features of RVA infections and to detect the emergence of potentially epidemic strains in France. From 2009 to 2014, RVA-positive stool samples were collected from 4800 children <5 years old attending the paediatric emergency units of 16 large hospitals. Rotaviruses were then genotyped by RT-PCR with regard to their outer capsid proteins VP4 and VP7. Genotyping of 4708 RVA showed that G1P[8] strains (62.2%) were predominant. The incidence of G9P[8] (11.5%), G3P[8] (10.4%) and G2P[4] (6.6%) strains varied considerably, whereas G4P[8] (2.7%) strains were circulating mostly locally. Of note, G12P[8] (1.6%) strains emerged during the seasons 2011-12 and 2012-13 with 4.1% and 3.0% prevalence, respectively. Overall, 40 possible zoonotic reassortants, such as G6 (33.3%) and G8 (15.4%) strains, were detected, and were mostly associated with P[6] (67.5%). Analysis of clinical records of 624 hospitalized children and severity scores from 282 of them showed no difference in clinical manifestations or severity in relation to the genotype. The relative stability of RVA genotypes currently co-circulating and the large predominance of P[8] type strains may ensure vaccine effectiveness in France. The surveillance will continue to monitor the emergence of new reassortants that might not respond to current vaccines, all the more so as all genotypes can cause severe infections in infants.

The conserved terminal region of Trichoderma reesei cellulases forms a strong antigenic epitope for polyclonal antibodies.

The specificity of polyclonal antibodies (Pab) raised against Trichoderma reesei cellulases has been studied. cDNAs lacking regions coding for certain functional domains were produced by preparing series of 3'-end deletions from the cDNAs for two cellobiohydrolases, CBH I and CBH II, and an endoglucanase, EG I. The proteins coded by the full length cDNAs and the truncated proteins coded by the deleted cDNAs were expressed in yeast Saccharomyces cerevisiae, under the control of the ADC1 promoter. Each polyclonal antiserum showed cross-reactivity with other cellulases. Pabs for CBH I and CBH II both recognized EG I. Pab for EG I strongly recognized both CBH I and CBH II. By analyzing the truncated proteins, we found that these antibodies were almost entirely directed against the conserved tail of the cellulase enzymes.

Relationship between GII.3 norovirus infections and blood group antigens in young children in Tunisia.

Noroviruses (NoVs) constitute a major cause of gastroenteritis in Tunisia. One hundred and fourteen matched saliva and stool samples were collected from children (n = 114) suffering from acute gastroenteritis at the hospital of Monastir during the winter season 2011-2012. For 98 of 114 children, blood samples were collected for secretor genotyping. NoVs were associated with 36.8% (n = 42/114) of the gastroenteritis cases. The GII.3 genotype was the most common (69% of all NoVs). For patients who were phenotyped (n = 114) for human blood group antigens (HBGAs), the secretor and non-secretor phenotypes represented 79% and 21%, respectively. Of the NoV infections, 83% were detected in all ABO groups. Five GII.3 isolates, one GII.1 isolate and one GII.7 isolate were detected in Lewis-positive non-secretors, confirmed by genotyping of the FUT2 gene. Even though our data showed that GII.3 NoVs could infect non-secretors, no binding was observed with saliva and GII.3 baculovirus-expressed virus-like particles from the same symptomatic non-secretor individual. This suggests that other factors might also participate in NoV attachment in children and newborns.

The members of the plakin family of proteins recognized by paraneoplastic pemphigus antibodies include periplakin.

Sera of patients with paraneoplastic pemphigus (PNP) characteristically immunoprecipitate five proteins, observations confirmed with the sera examined in this study. The proteins characterized thus far as autoantigens in PNP all belong to the plakin family of proteins and include desmoplakin, the 230 kDa bullous pemphigoid antigen, and envoplakin. The pattern of bands precipitated from metabolically labeled human keratinocyte extracts by each PNP serum was different, suggesting varying titers of antibodies against unique epitopes in various plakin family members. To further characterize this PNP antibody response, we produced fusion proteins of the homologous tail region of five plakin family members, including the recently cloned periplakin. Immunoblotting of equal amounts of each plakin tail-glutathione S-transferase fusion protein with PNP sera revealed a strong reaction with the envoplakin tail domain. Each sera also recognized periplakin, and certain sera recognized desmoplakin and plectin, and, weakly, bullous pemphigoid antigen 1. PNP sera were affinity purified with periplakin and envoplakin tail fusion proteins. Immunoprecipitation and immunoblotting with these affinity purified antibodies revealed shared as well as unique epitopes in the tail domains of these plakins. This study indicates that a homologous region in the carboxy-terminus of plakins, including the newly characterized periplakin, serves as an antigenic site in PNP.