Humoral response rate and predictors of response to BNT162b2 mRNA COVID19 vaccine in patients with multiple myeloma.

Multiple myeloma (MM) patients are at excess risk for clinically significant COVID19 infection. BNT162b2 mRNA COVID19 (BNT162b2) vaccine provides effective protection against COVID19 for the general population, yet its effect in MM patients may be compromised due to disease and therapy-related factors and was not yet evaluated. This single-centre prospective study included MM patients tested for serological response 14-21 days post second vaccine.

Single-Cell Transcriptomics Identifies the Adaptation of Scart1 Vγ6 T Cells to Skin Residency as Activated Effector Cells.

IL-17-producing γδ T cells express oligoclonal Vγ4 and Vγ6 TCRs, mainly develop in the prenatal thymus, and later persist as long-lived self-renewing cells in all kinds of tissues. However, their exchange between tissues and the mechanisms of their tissue-specific adaptation remain poorly understood. Here, single-cell RNA-seq profiling identifies IL-17-producing Vγ6 T cells as a highly homogeneous Scart1 population in contrast to their Scart2 IL-17-producing Vγ4 T cell counterparts.

Mutual interplay between IL-17-producing γδT cells and microbiota orchestrates oral mucosal homeostasis.

γδT cells are a major component of epithelial tissues and play a role in tissue homeostasis and host defense. γδT cells also reside in the gingiva, an oral tissue covered with specialized epithelium that continuously monitors the challenging dental biofilm. Whereas most research on intraepithelial γδT cells focuses on the skin and intestine epithelia, our knowledge on these cells in the gingiva is still incomplete.

Impaired Differentiation of Langerhans Cells in the Murine Oral Epithelium Adjacent to Titanium Dental Implants.

Peri-implantitis is a destructive inflammatory process affecting tissues surrounding dental implants and it is considered a new global health concern. Human studies have suggested that the frequencies of Langerhans cells (LCs), the main antigen-presenting cells (APCs) of the oral epithelium, are dysregulated around the implants. Since LCs play a role in regulating oral mucosal homeostasis, we studied the impact of dental titanium implants on LC differentiation using a novel murine model.

Cell-intrinsic regulation of murine epidermal Langerhans cells by protein S.

AXL, a member of the TYRO3, AXL, and MERTK (TAM) receptor tyrosine kinase family, has been shown to play a role in the differentiation and activation of epidermal Langerhans cells (LCs). Here, we demonstrate that growth arrest-specific 6 (GAS6) protein, the predominant ligand of AXL, has no impact on LC differentiation and homeostasis. We thus examined the role of protein S (PROS1), the other TAM ligand acting primarily via TYRO3 and MERTK, in LC function.

Porphyromonas gingivalis Promotes Unrestrained Type I Interferon Production by Dysregulating TAM Signaling via MYD88 Degradation.

Whereas type I interferons (IFNs-I) were proposed to be elevated in human periodontitis, their role in the disease remains elusive. Using a bacterial-induced model of murine periodontitis, we revealed a prolonged elevation in IFN-I expression. This was due to the downregulation of TAM signaling, a major negative regulator of IFN-I.

Analysis of Leukocytes in Oral Mucosal Tissues.

The oral mucosa is constantly exposed to an immense amount of microorganisms, while some colonize the various anatomical niches existing in the oral cavity. To deal with such a complex challenge, the oral mucosal immune system must tolerate commensal microorganisms but prevent invasion of pathogens. Such activity is likely to be achieved by a wide range of mechanisms that could be similar or different to those employed by other mucosal tissues.

GAS6 is a key homeostatic immunological regulator of host-commensal interactions in the oral mucosa.

The oral epithelium contributes to innate immunity and oral mucosal homeostasis, which is critical for preventing local inflammation and the associated adverse systemic conditions. Nevertheless, the mechanisms by which the oral epithelium maintains homeostasis are poorly understood. Here, we studied the role of growth arrest specific 6 (GAS6), a ligand of the TYRO3-AXL-MERTK (TAM) receptor family, in regulating oral mucosal homeostasis.