Monocyte differentiation antigen CD14 (CD14) (CD14)

Monocyte differentiation antigen CD14 (CD14) is a key pattern recognition receptor of the innate immune system, primarily expressed on the surface of monocytes, macrophages, and neutrophils (UniProt: P08571) [1]. It exists as a membrane-bound protein (mCD14) anchored by glycosylphosphatidylinositol or as a soluble form (sCD14) circulating in the plasma (Zanoni & Granucci, 2013) [2]. CD14 acts as a crucial co-receptor that facilitates the detection of lipopolysaccharide (LPS) from Gram-negative bacteria by transferring it to the Toll-like receptor 4 (TLR4)/MD-2 complex, thereby initiating a pro-inflammatory signaling cascade (PubMed: 23435335) [2, 3]. Beyond LPS, CD14 also participates in the recognition of other pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) through interactions with TLR2 and other receptors (NIH: PMC3601489) [2]. In pathological states such as sepsis, CD14-mediated overactivation leads to an uncontrolled cytokine storm, contributing to organ failure and systemic inflammation (PubMed: 32554444) [4]. Therapeutic strategies, such as the monoclonal antibody IC14 (atibuudimab), target CD14 to dampen this excessive inflammatory response in conditions like sepsis, acute respiratory distress syndrome (ARDS), and severe COVID-19 (ClinicalTrials.gov: NCT04391309) [5].

Other names

CD14LPS receptorCluster of differentiation 14

CD14 inhibition/neutralization to prevent the activation of Toll-like receptor complexes (TLR4/MD-2 and TLR2) by pathogen-associated molecular patterns.