Reticulocytes are immature
red blood cells, typically composing about 1% of the red cells in the human body. Reticulocytes develop and mature in the red bone marrowand then circulate for about a day in the blood stream before developing into mature red blood cells. Like mature red blood cells, reticulocytes do not have a cell nucleus. They are called reticulocytes because of a reticular (mesh-like) network of ribosomal RNAthat becomes visible under a microscope with certain stains such as new methylene blue.
To accurately measure reticulocyte counts, automated counters that use lasers mark cell samples with fluorescent dye that marks
RNAand DNA(such as thiazole orange). [cite book | author=Davis BH, Bigelow NC | year=1994 | chapter=Reticulocyte analysis and reticulocute maturity index | title=Flow cytometry. Methods in Cell Biology | volume=42 | editor=Darzynkiewicz Z, Crissman HA (eds.) | pages=263–74 | location=San Diego | publisher=Academic Press | isbn=0-12203-052-4 ] This distinguishes reticulocytes as the middle ground of dye response to laser light, between red blood cells (which have neither RNA nor DNA) and lymphocytes (which have a large amount of DNA, unlike reticulocytes). [http://www.medicaldesign.com/articles/ID/532]
The normal range of values for reticulocytes in the blood depends on the clinical situation and the lab, but broadly speaking is 0.5% to 1.5%. However, if a person has
anaemia, their reticulocyte percentage should be higher than "normal" if the bone marrow's ability to produce new blood cells remains intact. Thus, calculating the reticulocyte production indexis an important step in understanding whether the reticulocyte count is appropriate or inappropriate to the situation. This is often a more important question than whether the percentage is in the normal range; for instance, if someone is anemic but only has a reticulocyte percentage of 1%, this means that the bone marrow is likely not producing new blood cells at a rate that will correct the anemia. The number of reticulocytes is a good indicator of bone marrowactivity, because it represents recent production. This means that the reticulocyte count, and the reticulocyte production index that can be calculated from it, can be used to determine whether a production problem is contributing to the anaemia, and can also be used to monitor the progress of treatment for anaemia.
The specimen requirement for a reticulocyte count is
EDTAanti-coagulated whole blood (lavender-top bottle if using the Vacutainer, Vacuetteor Monojectsystems; red-top if using the S-Monovettesystem).
When there is an increased production of red blood cells to overcome chronic or severe loss of mature red blood cells, such as in a
haemolytic anaemia, people often have a markedly high number and percentage of reticulocytes. A very high number of reticulocytes in the blood can be described as reticulocytosis.
Abnormally low numbers of reticulocytes can be attributed to
chemotherapy, aplastic anaemia, pernicious anaemia, bone marrowmalignancies, problems of erythropoietinproduction, various vitamin or mineral deficiencies (B9, B12, iron), disease states ( anemia of chronic disease) and other causes of anaemia due to poor RBC production.
Reticulocytes appear slightly bluer than other red cells when looked at with the normal Romanowsky stain. Reticulocytes are also slightly larger, which can be picked up as a high MCV (mean corpuscular volume) with a full blood count done by a trained medical scientist, who has specialized in haematology, or a machine.
* [http://www.healthsystem.virginia.edu/internet/hematology/HessEDD/Redbloodcelldisorders/reticulocyte.cfm Reticulocytes] : Presented by the University of Virginia
* [http://www.diagnostic-medical-tests.com/hematology-coagulation-tests/reticulocyte-count.htm For more information on Reticulocyte Count]
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réticulocyte — [ retikylɔsit ] n. m. • v. 1930; de réticulé et cyte ♦ Méd. Jeune globule rouge présentant encore des granulations et un réseau de mitochondries visibles. ● réticulocyte nom masculin Globule rouge jeune. réticulocyte [ʀetikylɔsit] n. m. ÉTYM. V.… … Encyclopédie Universelle
Reticulocyte — Réticulocyte Le réticulocyte est la cellule précédant le stade d érythrocyte dans l érythropoïèse. Il lui est quasiment semblable. Les réticulocytes sont des globules rouges jeunes qui possèdent encore des ribosomes et des mitochondries. Ils sont … Wikipédia en Français
reticulocyte — reticulocyte. См. ретикулоцит. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
reticulocyte — [ri tik′yə lō sīt΄] n. [ModL < L reticulum (see RETICULE) + CYTE] a young circulating erythrocyte showing a network of fibers in the cell when stained reticulocytic [ri tik′yə lōsit′ik] adj … English World dictionary
Réticulocyte — Le réticulocyte est la cellule précédant le stade d érythrocyte dans l érythropoïèse. Il lui est quasiment semblable. Les réticulocytes sont des globules rouges jeunes qui possèdent encore des ribosomes et des mitochondries, mais dépourvues de… … Wikipédia en Français
reticulocyte — noun Etymology: New Latin reticulum + International Scientific Vocabulary cyte Date: 1922 an immature red blood cell that appears especially during regeneration of lost blood, lacks a nucleus, and has a fine basophilic reticulum formed of… … New Collegiate Dictionary
reticulocyte — Immature red blood cells found in the bone marrow, and in very small numbers in the circulation … Dictionary of molecular biology
reticulocyte — /ri tik yeuh leuh suyt /, n. Anat. a very young red blood cell, sampled as a measure of red blood cell formation; reticulated erythrocyte. [1920 25; RETICUL(UM) + O + CYTE] * * * … Universalium
reticulocyte — noun An immature red blood cell, having a reticular network of RNA … Wiktionary
reticulocyte — A young red blood cell containing a basophilic cytoplasmic network precipitated by brilliant cresyl blue representing residual polyribosomes; such cells become more numerous during the process of active blood regeneration. SEE ALSO … Medical dictionary