| Download the amazing global Makindo app: Android | Apple | |
|---|---|
| MEDICAL DISCLAIMER: Educational use only. Not for diagnosis or management. See below for full disclaimer. |
Monocytes
Related Subjects: |Iron deficiency Anaemia |Haemolytic anaemia |Macrocytic anaemia |Megaloblastic anaemia |Microcytic anaemia |Myelodysplasia |Myelofibrosis
๐งช Key Fact: Monocytes are the largest circulating leukocytes and act as precursors to tissue macrophages, playing a pivotal role in both innate defence and tissue repair.
๐ About
- Make up 2โ9% of circulating leukocytes.
- Circulate for 1โ3 days, then migrate into tissues where they can persist for weeksโyears as macrophages.
- Belong to the mononuclear phagocyte system (monocytes โ macrophages โ dendritic cells in some tissues).
- Differentiation depends on tissue environment:
- ๐ง Microglia (brain)
- ๐ซ Alveolar macrophages (lungs)
- ๐ Kupffer cells (liver)
- ๐ฆด Osteoclasts (bone)
- Highly phagocytic โ engulf pathogens, apoptotic cells, and necrotic debris.
๐งฌ Granules & Lysosomal Enzymes
- ๐งช Acid hydrolases โ digest cellular debris.
- ๐งช Aryl sulphatase โ break down sulphate esters.
- ๐งช Acid phosphatase โ degrade engulfed material.
- ๐งช Peroxidase โ generate microbicidal oxidative radicals.
โก Functions
- ๐จ First responders โ rapidly recruited to sites of infection, inflammation, or necrosis.
- ๐ฆ Differentiate into macrophages โ clear pathogens & debris via phagocytosis.
- ๐ก Antigen presentation โ activate T cells by displaying processed peptides on MHC class II.
- ๐ข Cytokine secretion: IL-1 (fever), TNF-ฮฑ (inflammation), IL-12 (Th1 differentiation).
- ๐ Bridge innate immunity with adaptive immune responses.
| The content on this website is provided for educational and informational purposes only to support exam preparation (e.g., MLA, MRCP, USMLE) and learning. This is NOT medical advice, diagnosis, treatment, or professional guidance. It does not replace consultation with a qualified healthcare professional, official guidelines (e.g., NICE, GMC, BNF), or supervised clinical practice. Always verify information with current, authoritative sources. Makindo and its contributors accept no liability for any reliance on this content, including errors, omissions, or any resulting harm, loss, or consequences. By using this site, you agree to these terms. |
|
|
Categories
- A Level
- About
- Acute Medicine
- Anaesthetics and Critical Care
- Anatomy
- Anatomy and Physiology
- Biochemistry
- Book
- Cardiology
- Collections
- CompSci
- Crib Sheets
- Crib sheets
- Dental
- Dermatology
- Differentials
- Drugs
- ENT
- Education
- Electrocardiogram
- Embryology
- Emergency Medicine
- Endocrinology
- Ethics
- Foundation Doctors
- GCSE
- Gastroenterology
- General Practice
- Genetics
- Geriatric Medicine
- Guidelines
- Gynaecology
- Haematology
- Hepatology
- Immunology
- Infectious Diseases
- Infographic
- Investigations
- Lists
- Mandatory Training
- Medical Students
- Microbiology
- Nephrology
- Neurology
- Neurosurgery
- Nutrition
- OSCE
- OSCEs
- Obstetrics
- Obstetrics Gynaecology
- Oncology
- Ophthalmology
- Oral Medicine and Dentistry
- Orthopaedics
- Paediatrics
- Palliative
- Pathology
- Pharmacology
- Physiology
- Procedures
- Psychiatry
- Public Health
- Radiology
- Renal
- Respiratory
- Resuscitation
- Revision
- Rheumatology
- Statistics and Research
- Stroke
- Surgery
- Toxicology
- Trauma and Orthopaedics
- USMLE
- Urology
- Vascular Surgery