Exocrine gland-resident memory CD8 T cells use mechanosensing for tissue surveillance.

Tissue-resident CD8 T cells (T) continuously scan peptide-MHC (pMHC) complexes in their organ of residence to intercept microbial invaders. Recent data showed that T lodged in exocrine glands scan tissue in the absence of any chemoattractant or adhesion receptor signaling, thus bypassing the requirement for canonical migration-promoting factors. The signals eliciting this noncanonical motility and its relevance for organ surveillance have remained unknown.

Explosive COVID-19 outbreak in a German nursing home and the possible role of the air ventilation system.

Background: Most COVID-19 outbreaks in nursing homes are explained by transmission of SARS-CoV-2 from nurses or visitors.

Methods And Results: We describe an outbreak with 64 of the 67 residents identified as COVID-19 cases within two weeks (34 in nursing block 1, 30 in nursing block 2), at least 32 of them had relevant symptoms of COVID-19. Thirteen of the residents' deaths were associated with COVID-19.

Metastatic Breast Cancer Recurrence after Bone Fractures.

Experimental studies suggest that bone fractures result in the release of cytokines and cells that might promote metastasis. Obtaining observational data on bone fractures after breast cancer diagnoses related to distant breast cancer recurrence could help to provide first epidemiological evidence for a metastasis-promoting effect of bone fractures. We used data from the largest German statutory health insurance fund (Techniker Krankenkasse, Hamburg, Germany) in a population-based cohort study of breast cancer patients with ICD-10 C50 codes documented between January 2015 and November 2019.

The Tec Kinase Itk Integrates Naïve T Cell Migration and Homeostasis.

Naïve T cells (T) constitutively recirculate through secondary lymphatic organs (SLOs), where they scan dendritic cells (DCs) for cognate peptide-loaded major histocompatibility complexes (pMHC). Continuous trafficking between SLOs not only enables rapid clonal selection but also ensures T homeostasis by providing access to prosurvival signals from TCR, IL-7R, and the chemokine receptor CCR7. Inside the lymphoid tissue, CCR7-mediated T motility is mainly driven by the Rac activator DOCK2, with a separate contribution by a phosphoinositide-3-kinase γ (PI3Kγ)-dependent pathway.

JAML promotes CD8 and γδ T cell antitumor immunity and is a novel target for cancer immunotherapy.

T cells are critical mediators of antitumor immunity and a major target for cancer immunotherapy. Antibody blockade of inhibitory receptors such as PD-1 can partially restore the activity of tumor-infiltrating lymphocytes (TILs). However, the activation signals required to promote TIL responses are less well characterized.

Get in Touch With Dendritic Epithelial T Cells!

Innate and adaptive immune systems continuously interchange information and orchestrate their immune responses to protect the host. γδT cells play crucial roles, as they incorporate both innate and adaptive immune characteristics. Dendritic epidermal T cells (DETC) are specialized γδT cells, which are uniquely positioned to rapidly respond to skin wounds and infections.

Salivary gland macrophages and tissue-resident CD8 T cells cooperate for homeostatic organ surveillance.

It is well established that tissue macrophages and tissue-resident memory CD8 T cells (T) play important roles for pathogen sensing and rapid protection of barrier tissues. In contrast, the mechanisms by which these two cell types cooperate for homeostatic organ surveillance after clearance of infections is poorly understood. Here, we used intravital imaging to show that T dynamically followed tissue macrophage topology in noninflamed murine submandibular salivary glands (SMGs).

Leukocyte Tracking Database, a collection of immune cell tracks from intravital 2-photon microscopy videos.

Recent advances in intravital video microscopy have allowed the visualization of leukocyte behavior in vivo, revealing unprecedented spatiotemporal dynamics of immune cell interaction. However, state-of-the-art software and methods for automatically measuring cell migration exhibit limitations in tracking the position of leukocytes over time. Challenges arise both from the complex migration patterns of these cells and from the experimental artifacts introduced during image acquisition.

Preparation of Murine Submandibular Salivary Gland for Upright Intravital Microscopy.

The submandibular salivary gland (SMG) is one of the three major salivary glands, and is of interest for many different fields of biological research, including cell biology, oncology, dentistry, and immunology. The SMG is an exocrine gland comprised of secretory epithelial cells, myofibroblasts, endothelial cells, nerves, and extracellular matrix. Dynamic cellular processes in the rat and mouse SMG have previously been imaged, mostly using inverted multi-photon microscope systems.

WNK1 kinase balances T cell adhesion versus migration in vivo.

Adhesion and migration of T cells are controlled by chemokines and by adhesion molecules, especially integrins, and have critical roles in the normal physiological function of T lymphocytes. Using an RNA-mediated interference screen, we identified the WNK1 kinase as a regulator of both integrin-mediated adhesion and T cell migration. We found that WNK1 is a negative regulator of integrin-mediated adhesion, whereas it acts as a positive regulator of migration via the kinases OXSR1 and STK39 and the ion co-transporter SLC12A2.

Thromboxane A2 acts as tonic immunoregulator by preferential disruption of low-avidity CD4+ T cell-dendritic cell interactions.

Interactions between dendritic cells (DCs) and T cells control the decision between activation and tolerance induction. Thromboxane A2 (TXA2) and its receptor TP have been suggested to regulate adaptive immune responses through control of T cell-DC interactions. Here, we show that this control is achieved by selectively reducing expansion of low-avidity CD4(+) T cells.