Related Experiment Video
Updated: Jan 9, 2026

Isolation and Th17 Differentiation of Naïve CD4 T Lymphocytes
Published on: September 26, 2013
Compartment-Specific NK Cell Phenotypes Reveal Distinct Maturation and Activation States in Inflammatory Arthritis
Franca Sophie Deicher1,2, Tarik Exner3, Maren Claus4
1Department of Rheumatology, University Hospital Düsseldorf, Medical Faculty of Heinrich-Heine-University, Dusseldorf, Germany.
Abstract:
Introduction: Synovial natural killer (NK) cells contribute to inflammation in arthritis by secreting cytokines and modulating synovial fibroblast activation. The aim of this study was to describe systemic versus local inflammatory changes of NK cell subsets as well as their physical cell-cell interactions in arthritis patients.
Methods:
Spectral flow cytometry was used to compare paired peripheral blood (PB) and synovial fluid (SF) immune cells from patients with active inflammatory arthritis and healthy controls. Physical cell-cell interactions within tissues were studied by applying a recently developed cellular interaction mapping framework.
Results:
Our paired approach revealed significant local enrichment of immature and activated NK cells in SF, characterized by elevated markers of early differentiation, immune-checkpoint regulation, and tissue-residency, highlighting tightly controlled immune activation at inflamed sites. Single-cell analysis confirmed heterogeneity within SF-NK cells, suggesting multiple co-existing activation states and developmental stages. PB-NK cells from patients differed profoundly compared to healthy controls, showing less immature NK cell subsets and an enrichment of mature, pro-inflammatory subsets indicative of systemic immune activation. Cellular interaction mapping revealed mainly NK/neutrophil interactions of patients' NK cells, while interactions with B-cells, T-cells, or monocytes were negligible. T-cells also displayed profound local and systemic alterations. Cellular interaction mapping revealed that next to NK/neutrophil interactions, interactions between B-cells with monocytes and T-cells with neutrophils characterize joint inflammation.
Conclusion:
This paired high-dimensional analysis revealed systemic and local alterations in NK cell subsets shaped by co-existing developmental stages and immune regulatory mechanisms. Cellular interaction mapping indicated that neutrophils are a main interaction-partner of NK cells in inflamed joints.
.Related Concept Videos
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
T Cell Activation and Clonal Selection
Naive T cells that have not yet encountered an antigen express two primary CD...
NF-κB-dependent Signaling Pathway
NF-κB-dependent Signaling Mechanism
The...
Cells of the Innate Immune Response
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
B Cell Activation and Differentiation
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
Immune Surveillance by NK Cells and Phagocytes
Natural Killer Cells: The Fast Responders
NK cells are large granular lymphocytes found in the blood and lymphatic system. These...

