Actin Cytoskeletal Dynamics in Immunological Disorders

The actin cytoskeleton orchestrates fundamental aspects of immune cell function, including migration, adhesion, antigen presentation and effector responses. Dynamic remodelling of actin filaments through processes of nucleation, branching and disassembly enables leukocytes to patrol tissues, form immunological synapses and execute targeted cytotoxic or phagocytic activities. Genetic defects or dysregulation of actin‐regulatory proteins—such as nucleation‐promoting factors, Arp2/3 complex subunits and Rho family GTPases—may give rise to a spectrum of immunological disorders, ranging from primary immunodeficiencies characterised by recurrent infections and impaired cellular activation, to autoinflammatory syndromes and autoimmune phenomena. Recent advances have illuminated how specific mutations perturb actin architecture across diverse lineages—platelets, neutrophils, macrophages and T lymphocytes—leading to cytopenias, tissue inflammation and compromised barrier immunity. An improved mechanistic understanding of actin dynamics offers new avenues for targeted interventions that restore cytoskeletal balance and ameliorate immune dysfunction on a global scale.

Research from Nature Portfolio

Recent studies have identified germline biallelic null mutations in ARPC5, a core component of the Arp2/3 actin nucleator, in patients with severe infections, early‐onset autoimmunity and developmental anomalies. Functional assays demonstrate that restoration of ARPC5 expression rescues Arp2/3 complex conformation, reconstitutes actin branching and normalises differential interleukin-6 signalling, suggesting precise molecular targets for therapeutic modulation. In parallel, investigation of ARPC1B deficiency reveals that loss of this Arp2/3 subunit underlies a distinct immuno‐haematopoietic syndrome featuring microthrombocytopenia, eosinophilia and inflammatory manifestations. Characterisation of patient‐derived platelets and megakaryocytic progenitors confirms that ARPC1B is non‐redundant within blood lineages, emphasising the importance of isoform specificity in actin‐mediated immune homeostasis.

Actin Cytoskeletal Dynamics in Immunological Disorders publication trend

The graph below shows the total number of articles in actin cytoskeletal dynamics in immunological disorders across all publications each year (not limited to Nature Index journals).

Technical terms

Actin cytoskeleton: Network of filamentous actin structures that provides mechanical support and drives cell motility.

Arp2/3 complex: Heptameric protein assembly that nucleates branched actin filaments essential for membrane protrusions.

Rho GTPase: Family of small GTP-binding proteins regulating actin dynamics, cell polarity and trafficking.

Lamellipodia: Broad, sheet-like plasma membrane protrusions formed by branched actin networks at the leading edge of migrating cells.

Immunological synapse: Specialized cell–cell junction between T cells and antigen-presenting cells that organises signalling and secretion.

Nucleation-promoting factor: Protein that activates the Arp2/3 complex to initiate new actin filament branches.

References

1. Inherited ARPC5 mutations cause an actinopathy impairing cell motility and disrupting cytokine signaling. Nature Communications (2023).
2. Loss of the Arp2/3 complex component ARPC1B causes platelet abnormalities and predisposes to inflammatory disease. Nature Communications (2017).
3. Role of Rho GTPases in inflammatory bowel disease. Cell Death Discovery (2023).
4. Actin Remodeling Defects Leading to Autoinflammation and Immune Dysregulation. Frontiers in Immunology (2021).
5. Loss of ARPC1B impairs cytotoxic T lymphocyte maintenance and cytolytic activity. Journal of Clinical Investigation (2019).