IgD shapes the pre-immune naïve B cell compartment in humans

B cell maturation and immunoglobulin (Ig) repertoire selection are governed by expression of a functional B cell receptor (BCR). Naïve B cells co-express their BCR as IgM and IgD isotype. However, the role of the additionally expressed IgD on naïve B cells is not known. Here we assessed the impact of IgD on naïve B cell maturation and Ig repertoire selection in 8 individuals from 3 different families with heterozygous loss-of-function or loss-of expression mutations in IGHD. Although naïve B cells from these individuals expressed IgM on their surface, the IGHD variant in heterozygous state entailed a chimeric situation by allelic exclusion with almost half of the naïve B cell population lacking surface IgD expression. Flow cytometric analyses revealed a distinct phenotype of IgD-negative naïve B cells with decreased expression of CD19, CD20 and CD21 as well as lower BAFF-R and integrin-β7 expression. IgD-negative B cells were less responsive in vitro after engaging the IgM-BCR, TLR7/9 or CD40 pathway. Additionally, a selective disadvantage of IgD-negative B cells within the T2 transitional and mature naïve B cell compartment as well as reduced frequencies of IgMlo/- B cells within the mature naïve B cell compartment lacking IgD were evident. RNA-Ig-seq of bulk sorted B cell populations showed an altered selection of distinct VH segments in the IgD-negative mature naïve B cell population. We conclude that IgD expression on human naïve B cells is redundant for generation of naïve B cells in general, but further shapes the naive B cell compartment starting from T2 transitional B cells. Our observations suggest an unexpected role of IgD expression to be critical for selection of distinct Ig VH segments into the pre-immune Ig repertoire and for the survival of IgMlo/- naïve B cells known to be enriched in poly-/autoreactive B cell clones

Successful treatment of recalcitrant cutaneous sarcoidosis with fumaric acid esters

BACKGROUND: Sarcoidosis is a multisystem disease of unknown origin characterized by the formation of noncaseating granulomas, in particular in the lungs, lymph nodes, eyes, and skin. Systemic treatment for cutaneous sarcoidosis can be used for large disfiguring lesions, generalized involvement, or recalcitrant lesions that did not respond to topical therapy. CASE PRESENTATIONS: We report three patients with recalcitrant cutaneous sarcoidosis who were treated with oral fumaric acid esters (FAE). Three female patients presented with cutaneous sarcoidosis that have proved to be refractory to various therapies, including corticosteroids and chloroquine. We treated the patients with FAE in tablet form using two formulations differing in strength (Fumaderm(® )initial, Fumaderm(®)). Dosage of FAE was performed according to the standard therapy regimen for psoriasis patients. After treatment with FAE (4–12 months), a complete clearance of skin lesions was achieved in the three patients. The side effects observed in this trial correspond to the well-known spectrum of adverse effects of FAE (flush, minor gastrointestinal complaints, lymphopenia). CONCLUSIONS: On the basis of our findings FAE therapy seems to be a safe and effective regimen for patients with recalcitrant cutaneous sarcoidosis. Nevertheless further investigations are necessary to confirm our preliminary results

Формоутворення великопрогонових світлопрозорих металевих конструкцій покриття

Dandelion (Taraxacum officinale) possesses an unusually high degree of disease resistance. As this plant exhibits high polyphenol oxidase (PPO) activity and PPO have been implicated in resistance against pests and pathogens, we analyzed the potential involvement of five PPO isoenzymes in the resistance of dandelion against Botrytis cinerea and Pseudomonas syringae pv. tomato. Only one PPO (ppo-2) was induced during infection, and ppo-2 promoter and beta-gincuronidase marker gene fusions revealed strong induction of the gene surrounding lesions induced by B. cinerea. Specific RNAi silencing reduced ppo-2 expression only, and concomitantly increased plant susceptibility to P. syringae pv. tomato. At 4 days postinoculation, P syringae pv. tomato populations were strongly increased in the ppo-2 RNAi lines compared with wild-type plants. When the dandelion ppo-2 gene was expressed in Arabidopsis thaliana, a plant having no PPO gene, active protein was formed and protein extracts of the transgenic plants exhibited substrate-dependent antimicrobial activity against P. syringae pv. tomato. These results clearly indicate a strong contribution of a specific, single PPO isoform to disease resistance. Therefore, we propose that specific PPO isoenzymes be included in a new family of pathogenesis-related (PR) proteins

Guidelines of the European Resuscitation Council (ERC) on cardiopulmonary resuscitation 2021: update and comments

The European guidelines on cardiopulmonary resuscitation, which are divided into 12 chapters, have recently been published. In addition to the already known chapters, the topics epidemiology and life-saving systems have been integrated for the first time. For each chapter five practical key statements were formulated. In the present article the revised recommendations on basic measures and advanced resuscitation measures in adults as well as on postresuscitation treatment are summarized and commented on

Guidelines of the European Resuscitation Council (ERC) on cardiopulmonary resuscitation 2021: update and comments

The European guidelines on cardiopulmonary resuscitation, which are divided into 12 chapters, have recently been published. In addition to the already known chapters, the topics epidemiology and life-saving systems have been integrated for the first time. For each chapter five practical key statements were formulated. In the present article the revised recommendations on basic measures and advanced resuscitation measures in adults as well as on postresuscitation treatment are summarized and commented on