Molecular Classification
Biological System, Cellular Signaling Network, Immune Pathway
Other Names
Cell-mediated immunity, Immune system signaling, Intercellular immune communication, Immune synapse and paracrine signaling
Disease Roles
CancerAutoimmune diseaseInfection

Cellular immune system via cell-cell contact and secretome Overview

The cellular immune system operates through a combination of direct cell-cell contact and the release of a complex secretome to coordinate host defense and maintain tissue homeostasis (NCBI, NBK279364). Cell-cell contact is mediated by specialized surface molecules, such as the interaction between the T-cell receptor (TCR) and the major histocompatibility complex (MHC), which is essential for antigen recognition and immune activation (PubMed, PMC3135642). Simultaneously, the secretome—comprising cytokines, chemokines, and extracellular vesicles—acts as a paracrine and endocrine signaling network to recruit and polarize immune cells (Nature Reviews Immunology, 2017). Dysregulation of these processes is central to the pathogenesis of various conditions, including cancer, where tumors evade immune detection, and autoimmune diseases, where the system attacks self-tissues (StatPearls, NBK459471). Therapeutic intervention often involves monoclonal antibodies that block inhibitory checkpoints or recombinant cytokines that stimulate immune effector functions (NIH, 2023). Because this term encompasses an entire physiological system and multiple signaling modalities, it does not represent a single druggable molecular target but rather a broad biological framework.

Mechanism of Action

Modulation of immune cell communication through the agonism or antagonism of cell-surface receptors and the neutralization or supplementation of secreted signaling proteins (PubMed, PMC7151665).

Biological Functions

Antigen presentation
Cytokine signaling
Leukocyte trafficking
Cell-mediated cytotoxicity
Immune homeostasis
Signal transduction

Disease Associations

Cancer
Autoimmune disease
Infection
Chronic inflammation
Immunodeficiency

Safety Considerations

  • Cytokine release syndrome (CRS)
  • Immune-related adverse events (irAEs)
  • Increased susceptibility to opportunistic infections
  • Systemic inflammatory response syndrome (SIRS)

Interacting Drugs

Pembrolizumab
Infliximab
Aldesleukin
Abatacept
Tocilizumab
Cyclosporine

Associated Biomarkers

Biomarker
Circulating cytokine levels (e.g., IL-6, TNF-alpha)
Immune cell phenotyping via flow cytometry
Expression levels of ligand-receptor pairs (e.g., PD-1/PD-L1)
C-reactive protein (CRP)