A Human Monoclonal Antibody Reacting with Merkel Cells: Immunofluorescence, Immunoperoxidase, and Immunoelectron Microscopy

A human monoclonal, mu, kappa, cold agglutinin antibody of the rare specificity Pr h (serum and proper eluates) was used in immunofluorescence and immunoperoxidase techniques and in immunoelectron microscopy on rabbit lip specimens. Pr h antibody strongly reacted with scattered cells in epidermis, which were demonstrated to be Merkel cells by electron microscopy; no nerve fibers were stained. In immunoelectron microscopy (IEM), a strong reaction was seen within the cytoplasm and around the granules. This is the first IEM staining of Merkel cells (MC) so far reported; it demonstrates the expression of a carbohydrate differentiation antigen in MC. The availability of a potent monoclonal antibody reacting with MC but not with neighboring epidermal cells in rabbit lip offers a new tool for the study of several aspects of MC biology, including antigenic properties and kinetics

Adult-onset Still's disease with persistent plaques

Adult-onset Still's disease (AOSD) is a systemic disorder characterized by intermittent fever, evanescent rash, arthralgias or arthritis and predominantly neutrophilic leucocytosis. We report on a 16-year-old woman with Still's disease who developed, in addition to the typical rash, persistent papular lesions on her face, neck and upper and lower back. Although the presence of fixed skin lesions is not a characteristic feature of AOSD, their appearance at the onset of the disease and their evolution suggest that they represent a specific manifestation of the disease

Neurological Symptom Improvement After Re-Irradiation in Patients With Diffuse Intrinsic Pontine Glioma: A Retrospective Analysis of the SIOP-E-HGG/DIPG Project.

Purpose: The aim of this study is to investigate the spectrum of neurological triad improvement in patients with diffuse intrinsic pontine glioma (DIPG) treated by re-irradiation (re-RT) at first progression. Methods: We carried out a re-analysis of the SIOP-E retrospective DIPG cohort by investigating the clinical benefits after re-RT with a focus on the neurological triad (cranial nerve deficits, ataxia, and long tract signs). Patients were categorized as "responding" or "non-responding" to re-RT. To assess the interdependence between patients' characteristics and clinical benefits, we used a chi-square or Fisher's exact test. Survival according to clinical response to re-RT was calculated by the Kaplan-Meier method. Results: As earlier reported, 77% (n = 24/31) of patients had any clinical benefit after re-RT. Among 25/31 well-documented patients, 44% (n = 11/25) had improvement in cranial nerve palsies, 40% (n = 10/25) had improvement in long-tract signs, and 44% (11/25) had improvement in cerebellar signs. Clinical benefits were observed in at least 1, 2, or 3 out of 3 symptoms of the DIPG triad, in 64%, 40%, and 24%, respectively. Patients irradiated with a dose ≥20 Gy versus <20 Gy may improve slightly better with regard to ataxia (67% versus 23%; p-value = 0.028). The survival from the start of re-RT to death was not different between responding and non-responding DIPG patients (p-value = 0.871). Conclusion: A median re-irradiation dose of 20 Gy provides a neurological benefit in two-thirds of patients with an improvement of at least one symptom of the triad. DIPG patients receiving ≥20 Gy appear to improve slightly better with regard to ataxia; however, we need more data to determine whether dose escalation up to 30 Gy provides additional benefits