platelet

Also known as thrombocyte W, thrombocytes, blood platelet, blood platelets, platelets

Platelets or thrombocytes () are a part of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping to form a blood clot. Platelets have no cell nucleus; they are fragments of cytoplasm from megakaryocytes which reside in bone marrow or lung tissue, and then enter the circulation. Platelets are found only in mammals, whereas in other vertebrates (e.g. birds, amphibians), thrombocytes circulate as intact mononuclear cells.

AI overview

Platelets are tiny fragments in your blood that work together with other clotting factors to stop bleeding by forming clots when blood vessels are injured. These cell fragments come from larger cells in your bone marrow and lungs, and unlike thrombocytes in other animals, mammalian platelets lack a nucleus.

AI-generated from the Wikipedia summary — may contain errors.

Key facts

Cell.Name: Platelets
Cell.Latin: thrombocytus
Cell.Image: Platelets2.JPG
Cell.Caption: Image from a light microscope (500 ×) from a Giemsa-stained peripheral blood smear showing platelets (small purple dots) surrounded by red blood cells (large gray circular structures)
Cell.Precursor: Megakaryocytes
Cell.Function: Formation of blood clots; prevention of bleeding

via Wikipedia infobox

Research

353,326 papers

Platelet proteomics.ReviewMass spectrometry reviews · 2012Zufferey A, Fontana P, Reny JL et al.DOI: 10.1002/mas.20345
Platelet heterogeneity: variety makes immune and vascular function better.ReviewBlood · 2025Malloy MW, McGrath KE, Morrell CNDOI: 10.1182/blood.2025028955
A Platelet's Guide to Synovitis.ReviewThe Israel Medical Association journal : IMAJ · 2019Cafaro G, Bartoloni E, Alunno A et al.
Platelet Subpopulations: Characteristics, Function, Clinical Relevance, and Translational Potential.ReviewClinics in laboratory medicine · 2025Song AB, Battinelli EDOI: 10.1016/j.cll.2025.07.009
Platelet's plea to Immunologists: Please do not forget me.ReviewInternational immunopharmacology · 2024Kumar V, Stewart Iv JHDOI: 10.1016/j.intimp.2024.113599
Platelet-Based Drug Delivery for Cancer Applications.ReviewAdvances in experimental medicine and biology · 2018Ortiz-Otero N, Mohamed Z, King MRDOI: 10.1007/978-3-319-95294-9_12
Platelet proteomics: Clinical implications - Decoding the black box!ReviewTransfusion and apheresis science : official journal of the World Apheresis Association : official journal of the European Society for Haemapheresis · 2025Goubran H, Ahmed S, Ragab G et al.DOI: 10.1016/j.transci.2024.104060
Platelet function.ReviewSeminars in thrombosis and hemostasis · 1977Henry RLDOI: 10.1055/s-0028-1087130

via PubMed

Wikidata facts

Image: Platelets collected by using apheresis.jpg

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Commons category: Platelets

Sources (5)

via Wikidata · CC0

~38 min read

Article

47 sections

Contents

Term
Structure
Shape
Development
Hemostasis
Adhesion
Activation
Inhibition
Trigger (induction)
Components (consequences)
GPIIb/IIIa activation
Granule secretion
Morphology change
Platelet-coagulation factor interactions: coagulation facilitation
Immune function
Immunothrombosis
Inflammation
Adaptive immunity
Measurement and testing
Measurement
Bleeding time
Multiple electrode aggregometry
Light transmission aggregometry
Whole blood impedance aggregometry
PFA-100
Clinical significance
Disorders
Thrombocytopenia
Altered platelet function
Thrombocytosis and thrombocythemia
Pharmacology
Anti-inflammatory drugs
Drugs that suppress platelet function
Oral agents
Intravenous agents
Drugs that stimulate platelet production
Therapies
Transfusion
Indications
Collection
Storage
Delivery
Wound repair
Non-mammals
History
See also
References

thumb|The ligands, denoted by letter L, signal for platelets (P) to migrate towards the wound (Site A). As more platelets gather around the opening, they produce more ligands to amplify the response. The platelets congregate around the wound in order to create a cap to stop blood flow out of the tissue.