Paraneoplastic pemphigus uncovers distinct clinical and biological phenotypes of western unicentric Castleman disease.

Unicentric Castleman disease (UCD) is a lymphoproliferative disease of unknown cause. Paraneoplastic pemphigus (PNP) is a major complication shown to be associated with a poor prognosis, with particular severity in patients with bronchiolitis obliterans (BO). This study describes the clinical and biological characteristics of UCD-PNP patients in a large Western cohort. A total of 148 patients diagnosed with UCD were identified, including 14 patients with a defined PNP. PNP was significantly associated with myasthenia gravis (MG) and FDC sarcoma during follow-up (FDCS). PNP was also significantly associated with reduced survival. These data, together with a multivariate analysis by principal components, led to the identification of UCD-PNP as a group at risk of MG, FDCS and death. PDGFRB sequencing performed on UCD lesions from six patients found the gain-of-function p.N666S variant in two. Interestingly, both patients had hyaline-vascular UCD subtype, were in the UCD-PNP subgroup and had FDCS. Sera from 25 UCD-PNP patients and 6 PNP patients without UCD were tested for PNP-associated autoantibodies. Sera from UCD-PNP patients had a strong reactivity against the N-terminal domain of recombinant periplakin (rPPL, 82%) and showed reactivity against at least two domains of rPPL. These features were not found in patients with UCD alone or in the PNP group without UCD. These data indicate that UCD-PNP patients belong to a subgroup sharing strong clinical and biological identity that might help to decipher the different dynamics of UCD natural history.

C-tag TNF: a reporter system to study TNF shedding.

TNF is a highly pro-inflammatory cytokine that contributes not only to the regulation of immune responses but also to the development of severe inflammatory diseases. TNF is synthesized as a transmembrane protein, which is further matured via proteolytic cleavage by metalloproteases such as ADAM17, a process known as shedding. At present, TNF is mainly detected by measuring the precursor or the mature cytokine of bulk cell populations by techniques such as ELISA or immunoblotting. However, these methods do not provide information on the exact timing and extent of TNF cleavage at single-cell resolution and they do not allow the live visualization of shedding events. Here, we generated C-tag TNF as a genetically encoded reporter to study TNF shedding at the single-cell level. The functionality of the C-tag TNF reporter is based on the exposure of a cryptic epitope on the C terminus of the transmembrane portion of pro-TNF on cleavage. In both denatured and nondenatured samples, this epitope can be detected by a nanobody in a highly sensitive and specific manner only upon TNF shedding. As such, C-tag TNF can successfully be used for the detection of TNF cleavage in flow cytometry and live-cell imaging applications. We furthermore demonstrate its applicability in a forward genetic screen geared toward the identification of genetic regulators of TNF maturation. In summary, the C-tag TNF reporter can be employed to gain novel insights into the complex regulation of ADAM-dependent TNF shedding.

Comparison of interdental cleaning methods: a randomized controlled trial.

BACKGROUND: Although interdental cleaning is an integral component of home plaque control for periodontally involved patients, limited data exist on the periodontal benefits of commonly used interdental cleaning methods before definitive root surface debridement is undertaken. Therefore, the aim of this study was to compare the effects of a customized interdental brushing technique and a customized flossing technique on clinical periodontal outcomes prior to root surface debridement in chronic periodontitis cases. METHODS: This was a single-blind, randomized controlled clinical trial. Seventy-seven patients with chronic periodontitis were measured for plaque, relative interdental papillae level, Eastman interdental bleeding index, probing depths, and bleeding on probing at interdental sites and underwent a 10-minute hand scaling to remove easily accessible calculus deposits. Before group allocation, patients were advised on toothbrushing and instructed in two customized methods of interdental cleaning involving dental floss and precurved interdental brushes. Materials were supplied after random allocation. Participants were recalled at 6 and 12 weeks for clinical measurements, reinforcement of instructions, and fresh materials. RESULTS: There were significant reductions from baseline for all indices in both groups (P <0.01). At 6 weeks, the interdental brush group improved more than the floss group in every parameter (P <0.05). By 12 weeks, the changes in plaque, papillae level, and probing depths were significantly greater in the interdental brush group than the floss group (P <0.01). CONCLUSION: This trial demonstrated that patients were able to improve clinical periodontal outcomes by interdental cleaning, particularly with interdental brushes, even before thorough root surface debridement was undertaken.