Pathogen-associated carbohydrate motifs (PACMs)

Pathogen-associated carbohydrate motifs (PACMs) are conserved glycan structures found on the surface of microorganisms, including bacteria, fungi, and viruses, which are recognized by the host's innate immune system (Nature Reviews Immunology, 2020). These motifs, such as lipopolysaccharides (LPS), peptidoglycans, and beta-glucans, function as Pathogen-Associated Molecular Patterns (PAMPs) that trigger immune responses through Pattern Recognition Receptors (PRRs) like C-type lectin receptors (Frontiers in Immunology, 2018). In clinical practice, PACMs are significant targets for vaccine development, where capsular polysaccharides are used to elicit protective immunity against pathogens like Streptococcus pneumoniae (CDC, 2023). They also serve as diagnostic biomarkers; for instance, the detection of galactomannan or (1,3)-beta-D-glucan is used to identify invasive fungal infections (Journal of Fungi, 2021). Therapeutic strategies targeting PACMs include the use of neutralizing agents like Polymyxin B for LPS or the development of glycomimetic drugs to block pathogen adhesion (Trends in Pharmacological Sciences, 2019). However, the structural complexity and diversity of these motifs present challenges in drug design and can lead to safety concerns such as excessive inflammatory activation (Sepsis, 2022).

Other names

Microbial carbohydrate patternsCarbohydrate PAMPsPathogen-associated molecular patterns (carbohydrates)Microbial glycans

Binding and neutralization of microbial surface glycans or activation of pattern recognition receptors (PRRs) to stimulate innate and adaptive immune responses.