Cytoplasm Information and Courses from MediaLab, Inc.

Lactate dehydrogenase is found in the cytoplasm of every cell. LD is present in the serum at a level of 100-190 U/L. The serum LD level will rise during increased cell damage.Persons with alpha thalassemia intermedia usually have an increased levels of lactate dehydrogenase (LD). This LD is of red blood cell origin, which leaks in to the plasma during hemolysis.

Seven mesothelial cells are seen in this slide. Notice that all of the nuclei have a distinct shape with no evidence of irregular division. Chromatin pattern is typical of cells that originate in the tissues. Cytoplasm is irregular and some pseudopods are evident, especially in the lower portion of the field.

The arrow in this slide is pointing to a monocyte. The nucleus has an open chromatin pattern which gives it a spongy appearance. There is another monocyte in the lower right corner of the field. The other two cells could be classified as macrophages (histiocytes) because the nucleus is oval or kidney bean-shaped and the cytoplasm is very irregular. After circulating in the blood for one to three days, monocytes enter the tissues. The tissue form of the monocyte is called a macrophage or histiocyte.

Blast cells may be seen in the spinal fluid when cell proliferation in acute leukemia or lymphoma spreads to the central nervous system. The arrows indicate the two blasts in this field. Notice the smooth chromatin pattern in the nucleus and prominent nucleoli in both cells. Notice that an Auer rod is present in the cytoplasm in the blast to the right. The Auer rod indicates that these blasts are myeloblasts rather than lymphoblasts. A segmented neutrophil and several red cells can also be seen.

Another example of a malignant cell. This cell has a smooth chromatin pattern similar to the chromatin pattern commonly seen in blast cells. This cell has a high nuclear to cytoplasm (NC) ratio which is typical for malignant cells. No nucleoli are visible in this cell although malignant cells often have large nucleoli.

Rouquette C. Berche P. The pathogenesis of infection by Listeria monocytogenes Microbiologia. 12:245-58, 1996 Listeria monocytogenes is a Gram-positive bacterium responsible for severe infections in human and a large variety of animal species. It is a facultative intracellular pathogen which invades macrophages and most tissue cells of infected hosts where it can proliferate. The molecular basis of this intracellular parasitism has been to a large extent elucidated. The virulence factors, including internalin, listeriolysin O, phospholipases and a bacterial surface protein, ActA, are encoded by chromosomal genes organized in operons. Following internalisation into host cells, the bacteria escape from the phagosomal compartment and enter the cytoplasm. They then spread from cell to cell by a process involving actin polymerisation. In infected hosts, the bacteria cross the intestinal wall at Peyer's patches to invade the mesenteric lymph nodes and the blood. The main target organ is the liver, where the bacteria multiply inside hepatocytes. Early recruitment of polymorphonuclear cells lead to hepatocyte lysis, and thereby bacterial release This causes prolonged septicaemia, particularly in immunocompromised hosts, thus exposing the placenta and brain to infection. The prognosis of listeriosis depends on the severity of meningoencephalitis, due to the elective location of foci of infection in the brain stem (rhombencephalitis). Despite bactericidal antibiotic therapy, the overall mortality is still high (25 to 30%).

Pappenheimer bodies are seen in the cytoplasm of mature and immature erythrocytes on a Wright's stained smear. They are composed of degenerating cellular remnants, which contain iron. Pappenheimer bodies are most likely caused by accelerated red cell division, or impaired hemoglobin synthesis. Pappenheimer bodies appear as small dark purple granular bodies of varying size frequently clustered in groups of two, three or more near the edge of the cell.

On a Wright's-stained smear, the presence of multiple dark blue particles or granules of varying size, scattered throughout the cytoplasm of erythrocytes in the reticulocyte stage is called basophilic stippling. There are two types of stippling, fine or diffuse, and coarse or punctate. The erythrocyte containing them may stain normally in other respects or it may be polychromatophilic.

A gene is a hereditary unit or sequence of the nucleotide bases ACGT, occupying a fixed location or locus on the chromosome. It is these genes that carry all the information for life processes.DNA is rewritten into 3 types of RNA, each with a specific task: Messenger RNA (mRNA)carries the protein message to the cytoplasm. Ribosomal RNA (rRNA) is the location of protein synthesis. Transfer RNA (tRNA) is responsible for amino acid transport.Each 3-base nucleotide sequence (codon) codes for a specific amino acid. Some amino acids have more than one codon to direct their placement; this is termed degeneracy.

After penetration of the cell membrane by the gp41, the HIV capsid enters the cell's cytoplasm. Next, cellular enzymes strip away the capsid so that the HIV genome is released. Also stripped away are proteins p24 and p17. Protein 24 coats the HIV genome and protein 17 lines the inside of the capsid.

Reticular cells (adventitial cells) provide structural support for the endothelial cells that line the venous sinus and the developing blood cells within the hematopoietic cord. The cytoplasm of the reticular cells is capable of extending itself in fiberlike strands deep into the hematopoietic cords. These strands provide a meshwork for the blood cells. Other types of cells which furnish support in the cord include macrophages and fat cells.

This slide shows a marrow aspiration smear with numerous ring sideroblasts. Normal red cell precursors have only one or at most two granules of iron in their cytoplasm. These abnormal red cell precursors have numerous iron containing granules in their cytoplasm indicating abnormal iron incorporation. This iron is actually incorporated into mitochondria. Ring sideroblasts can be seen in idiopathic sideroblastic anemia, and in sideroblastic anemia induced by drugs, lead poisoning, and alcohol abuse.

This slide shows an example of the youngest cell in the megakaryocyte series, the megakaryoblast. Megakaryoblasts have a fine chromatin structure with multiple nucleoli, and scant basophilic cytoplasm. Cytoplasmic tags are frequently seen. It may vary 20-50 microns in diameter.

The next stage is the meta megakaryocyte. By this point, platelets are actually breaking away from the meta megakaryocyte cytoplasm. The example shown in this slide illustrates the platelets forming and breaking away near the arrow.

Another example of a cell rarely seen in the bone marrow is an osteoblast. Osteoblasts are cells which are similar in appearance but somewhat larger than plasma cells or tumor cells. The nucleus is eccentric and the "hoff" area is sometimes located away from the nucleus. The cytoplasm appears rather foamy when compared to a plasma cell. The size of an osteoblast is 20-25 microns. Osteoblast produce bone.

Another rare but abnormal type of plasma cell is the Mott cell (morula cell). The compartments visible in the cytoplasm are immunoglobulins which have not been released. Mott cells may be seen in parasitic infections and malignant tumors.

It is also important to examine the morphology of platelets. One megakaryocyte shows a single nucleus surrounded by cytoplasm which will eventually break off to form platelets. The other one at the arrow shows a lobated nucleus which has divided several times; the large amount of cytoplasm surrounding this nucleus means that this cell will be able to produce more platelets. In general, as the megakaryocyte gets older, it forms more nuclear lobes, more cytoplasm and therefore is able to produce more platelets.

Another example of tumor cells under higher magnification, showing large cells with loose immature chromatin structure and ill-defined cytoplasm.

Megakaryocytes differ from other cell lines because the nucleus divides during mitosis but the cytoplasm does not.

The cytoplasm of platelets can be divided into two areas: the chromomere and the hyalomere. The chromomere is located centrally where the granules tend to aggregate. The hyalomere surrounds the chromomere and is a clear, blue, non-granular zone.

This diagram of platelets illustrate the central granular chromomere, and the peripheral clear hyalomere.

Antibody - A modified type of serum globulin synthesized by lymphoid tissue in response to antigenic stimulus. By virtue of specific combining sites each antibody reacts with only one antigen. Anucleate - Having no nucleus. Azurophilic granules - The well-defined large reddish granules (lysosomes) which may be present in large lymphocytes. They are called "azurophilic granules" because they stain blue with the azure stains which were originally used. Basophilic granules - Specific granules present in the cytoplasm of basophils. These granules are large and stain purple-black due to their strong affinity for basic stain. B-cell - Bone marrow derived lymphocytes which produce humoral antibodies. Biconcave - Having two concave surfaces. Cellular Immunity - The capacity of a small proportion of lymphoid population to exhibit response to a specific antigen. Chromomere - The centrally located granular portion of the platelet. Clone - A population of cells descended from a single cell. Delayed Hypersensitivity - (part of cellular immunity) that develops slowly over a period of 24-72 hours after an antigenic stimulus. It consists of an accumulation of cells around small vessels and/or nerves. Example: Tuberculin skin test reaction. Digestive Enzyme - A substance that catalyzes or accelerates the process of digestion. Eosinophilic Granules - Specific granules present in the cytoplasm of eosinophils. These granules are large, refractile spheres which stain reddish-orange due to their strong affinity for acid stain. Erythrocyte (red blood cell, RBC) - One of the elements found in peripheral blood. Normally the mature form is a non-nucleated, circular, biconcave disk adapted to transport respiratory gases. Fixed Macrophage - A phagocyte that is non-motile. Free Macrophage - An ameboid phagocyte present at the site of inflammation. Graft Rejection - A transplanted tissue that is rejected by the body's antibodies. Graft vs. Host Reaction - A complication that occurs when an implanted piece of tissue, which contains antibodies, rejects the host's tissue. Granulocyte - A leukocyte which contains granules in its cytoplasm, i.e., neutrophilic, eosinophilic, or basophilic granules. Half-life - is the length of time it takes for half of the cells circulating at a given time to leave the blood for the tissues. Hemocyte - Any blood cell or formed element of the blood. Hemostasis - A mechanism of the vascular system to arrest an escape of blood. It involves an interaction between blood vessels, platelets, and coagulation. Heparin - A mucopolysaccharide acid which, when present in sufficient amounts, functions as an anticoagulant by inhibiting thrombin. Histamine - A powerful dilator of capillaries and a stimulator of gastric secretions. Humoral Immunity - Acquired immunity produced after response to an antigenic stimulus in which B cells produce circulating antibodies. Hyalomere - the clear, blue non-granular zone surrounding the chromomere of a platelet. Immune Response - The interaction of a cell and an antigen that results in a proliferation of the cell and a capacity to produce antibodies. Isotonic Fluid - A fluid whose elements have an equal osmotic pressure. Leukocyte (white blood cell, WBC) - One of the formed elements of the blood; involved primarily with the body's defense. Lysosome - A microscopic body within cell cytoplasm; contains various enzymes, mainly hydrolytic, which are released upon injury to the cell. Megakaryocyte - A giant cell of the bone marrow from which platelets are derived. Mononuclear - A cell having a single nucleus.

Their cytoplasm is usually colorless or light blue. However, the color is usually masked by the large granules that are present. These granules take up the acid components of Wright-Giemsa stain, and are therefore reddish-orange.

The abundant cytoplasm of a segmented neutrophil is of virtually the same appearance as that of the band. It stains faintly pink and contains numerous fine specific granules which are pinkish-lilac.

Frequently, cytoplasmic vacuoles are present. These vacuoles appear as unstained areas or "holes" in the cytoplasm.

Small lymphocytes have only a thin rim of clear, homogenous, moderate blue cytoplasm around the nucleus.

The monocyte cytoplasm is opaque rather than transparent. One would be unable to read imaginary print placed behind the cell.

At times it can be very difficult to differentiate monocytes from large lymphocytes.Monocytes may be mistaken for large lymphs when their cytoplasm stains too lightly, when the characteristic granules are indistinct, or when the nucleus is rounded or only slightly indented.Sometimes a cell will have the nucleus of a lymphocyte and the cytoplasm of a monocyte, or some other confusing combination of characteristics.In order to properly identify the cell, it is necessary to weigh all of the characteristics together to determine which cell type it most resembles.Even then it is occasionally necessary to judge the cell on the basis of the company it keeps.For instance, if there are many monocytes, but few large lymphocytes around, the confusing cell is probably a mono.

Pappenheimer bodies are iron-containing granules that aggregate with mitochondria and are deposited in RBC or normoblast cytoplasm. Small and irregular, they are found only in pathological states as thalassemia and sideroblastic anemias(upper image). Wright-Giemsa stain defines the cytoplasmic content (protein), but Prussian blue staining is necessary to define the iron content, the essence of the Pappenheimer body (lower image). Pappenheimer bodies lie typically in small clusters (upper image) and tend to locate at the periphery of the red cell cytoplasm. A cluster is typically smaller than a single Howell-Jolly body.

Hemoblobin H disease follows deletions of 3 of the 4 alpha globulin chains. Beta chains, unable to bind with insufficient numbers of alpha chains, form beta chain tetramers, or HbH.These beta chain tetramers appear as numerous dot size inclusions in erythrocyte cytoplasm, best seen in supravital brilliant cresyl blue stains (lower photograph).The most common molecular defect in alpha thalassemia is DELETION, not MUTATION; whereas, in beta thalassemia, the molecular defect is MUTATION.Leptocytes, as illustrated in the upper photograph,(lepto, derived from a Greek word meaning thin, fine, or slight), are characteristic of HbH disease. They have thinner cell membranes than the cells we recognize as target cells. They stain more lightly than normal erythrocytes and their centers are almost colorless.Subtle changes perhaps, but worth keeping in mind

Several erythrocyte abnormalities are present in both the upper and lower photomicrographs. Many of these atypical cells are probably present as a result of the patient's splenectomy. Considerable anisocytosis and poikilocytosis with many tear-drop cells, bite cells, fragmented forms, and a few target cells are apparent. Some of the erythrocytes in the upper frame contain Howell-Jolly bodies (DNA fragments) that may be single or multiple, especially in myeloproliferative disorders. These inclusions stain negatively for iron and are eccentrically placed in the red cell cytoplasm. .

There are a number of abnormalities of sperm morphology. Abnormal heads can include enlarged head, double head, round head, constricted head, amorphous head, pinhead, and acute tapering forms. There are also heads with abnormal numbers of vacuoles. Midpiece abnormalities include distended and thin midpiece regions. Abnormal tails include short tails, double, triple or multiple tails, coiled tails, broken tails, or absent tail. Cytoplasmic droplets are also seen in some specimens. These are large regions of cytoplasm just below the head assumed to represent failure of complete sperm maturation or a sign of either toxicity or oxidation. There have also been reports that cytoplasmic droplets may be artifacts from the fixation and staining for morphology analysis.

The most common type of cell seen in the urine sediment is the epithelial cell. This slide shows squamous epithelial cells under low power brightfield microscopy. They appear as large flattened cells with abundant cytoplasm and small round central nucleus. Although squamous epithelial cells have little clinical significance they must be differentiated from other cellular elements.

Using phase contrast and high power the cytoplasm and nucleus appear much darker. Note the folded edge of the cytoplasm which is characteristic of squamous cells. The long, thread-like structures are mucous strands.

When examining a slide made from an EDTA tube of normal blood, an occasional cell containing a round pyknotic nucleus and neutrophilic-appearing cytoplasm may be seen. Rare cells such as these do not indicate the presence of Pelger-Huet anomaly.

Unusually dark staining Dohle bodies are seen in the cytoplasm of this cell, along with bacteria, an infrequent finding. The bacteria are round and stain almost black. The Dohle bodies are patches of dark blue stained material.

Two blasts are seen in this field. The lower one contains an Auer rod in the cytoplasm near 7 o'clock. It is similar to the one that the technologist saw when she was examining Monica McMurray's slide.

The vacuoles seen in the cytoplasm of this cell are somewhat smaller and several are located near the lower edge of the cytoplasm.

Several Auer rods can be seen in the cytoplasm of this cell at approximately 12 o'clock.

May-Hegglin bodies stain blue and appear to have a more definite shape than Dohle bodies. When examined under electron microscopy, they appear to be aggregates of thread-like structures in a crystal-like arrangement. May-Hegglin inclusions are RNA material believed to be derived from the endoplasmic reticulum. May-Hegglin bodies can be seen in monocytes and platelets as well as in all mature granulocytes. The platelets in May-Hegglin anomaly are very bizarre in appearance and thrombocytopenia is usually noted. When examining a slide that has bizarre platelets and blue-appearing bodies in the cytoplasm, thought should be given to the possibility of the May-Hegglin anomaly.

Toxic granulation is manifested by the presence of large granules in the cytoplasm of segmented and band neutrophils in the peripheral blood. The color of these granules can range from dark purplish blue to an almost red appearance. Toxic granules are azurophilic granules normally present in early myeloid forms, but which are not normally seen at the band and segmented stages of neutrophil maturation. These granules contain peroxidases and hydrolases. Toxic granulation is seen in cases of severe infection, as a result of denatured proteins in rheumatoid arthritis or, less frequently, as a result of autophagocytosis. Infection is the most frequent cause of toxic granulation. This type of granulation may be seen in cells which also contain Dohle bodies and/or vacuoles. Cells containing toxic granules may have decreased numbers of specific granules. Cells containing only a few specific granules, with or without toxic granules, are said to be degranulated. The nucleus in degranulated cells may often be round-bilobed, smooth and pyknotic. This type of nucleus is the result of aging and will disintegrate soon. Increased basophilia of azurophilic granules simulating toxic granules may occur in normal cells with prolonged staining time or decreased pH of the stain.

There are two large vacuoles (unstained areas in the cytoplasm) present in this cell.

Chediak-Higashi syndrome is a rare autosomal recessive disorder. It results from a mutation of the gene LYST which encodes a protein with multiple phosphorylation sites. This defect causes a cellular abnormality involving the fusion of cytoplasmic granules. Early in neutrophil maturation normal azurophilic granules form, but they fuse together to form megagranules. Later during the myelocyte stage, normal specific granules form. The mature neutrophils contain both normal specific granules and abnormal azurophilic granules. These large abnormal granules can be seen in the cytoplasm of neutrophils, eosinophils, basophils, monocytes and lymphocytes. These abnormal granules are able to kill bacteria in neutrophils and monocytes; however, the process is much less effective than in normal cells in part, because these neutrophils have impaired locomotion. For these reasons, individuals with Chediak-Higashi have recurrent infections. An accelerated lymphoma-like phase occurs, with lymphadenopathy, hepatosplenomegaly, and pancytopenia. Death often occurs at an early age.

The large cell illustrated in this photograph of a Wright/Giemsa-stained bone marrow smear is a megakaryocyte. This megakaryocyte appears mature. The nucleus has at least 8 lobes and the nuclear chromatin is coarse and distinct. Clusters of young platelets are being released from distinct platelet territories at the periphery of the cytoplasm (blue arrows). When mature, each megakaryocyte produces approximately 4000 platelets/day. Production can expand by 8-fold during times of increased demand and under the stimulus of thrombopoietin.

Large inclusions in leukocyte cytoplasm appear with Alder-Reilly syndrome. Inheritance patterns are not completely clear. The condition is characterized by larger than usual azurophilic and deeply violet staining granules clustered throughout the cytoplasm (even covering the nucleus)in all granulocytes. There are variations in which some lymphocytes and monocytes may be affected. These inclusions represent partially degraded mucopolysaccharides within lysosomes.Alder-Reilly bodies may be found independently of genetic mucopolysaccharidoses as an inherited anomaly (Jordan's anomaly). Cytoplasmic vacuoles of toxic origin are not present in Alder-Reilly cells. The background condition in Alder-Reilly syndrome is mucopolysaccharidosis with various types of bone and cartilage disorders, reported first in gargoylism, then in Hunter and Hurler syndromes. Accompanying conditions are hepatosplenomegaly, corneal opacities, and mental retardation. Reference: Brunning, Richard D. Morphologic Alterations in Nucleated Blood and Marrow Cells in Genetic Disorders. Human Pathol: 99-124, March, 1970

A 17-year-old young woman was admitted to the hospital with abdominal pain and a tentative diagnosis of appendicitis.The total white blood count was 14,500 cells/cumm with a left shift and neutrophils with changes tagged by the arrow in the photographs (see blue arrow).The bluish-staining, blurred accumulations in the cytoplasm (Doehle bodies), are located at the cell periphery in neutrophils with toxic changes.Doehle bodies are remnants of endocytoplasmic reticulum and are products of cytokine activity in the induction and shortened activity of neutrophil activation.They are often present in conditions with increased neutrophil lysosomal activity, manifest as toxic granulation.In this case, the presence of Doehle bodies serves as markers for infection-induced leukocytosis and supports the diagnosis of acute appendicitis.

A basophil and a small lymphocyte are compared in the same field of the upper photograph, A single basophil is shown in the lower photograph.The cytoplasmic granules of the basophil are larger than the granules of toxic granulation.They contain chemical mediators of immediate hypersensitivity, and are found in the cytoplasm and overlying the nucleus (better seen in the lower photograph). Basophilic granules stain metachromatically with toluidine blue indicating the presence of acid mucopolysaccharide or proteoglycans, both thought to be heparin or heparin-like substances.Basophils are related to tissue mast cells, each involved in hypersensitivity responses and following anaphylactic episodes.Under the stimulation of complement components C3a and C5a, many mediators are released from the basophil granules, including histamine, heparin, and eosinophil chemotactic factors of anaphylaxis, or ECF-A.Basophils are the least common neutrophils in the peripheral blood, comprising 2% or less of the differential count.The presence of large granules of irregular size in basophils and the admixture of eosinophilic granules may indicate dysplastic changes associated with myelodysplastic disorders and leukemia.

In this photograph of blood cells from yet another submitted slide, we find cells resembling lymphoblasts with increased nuclear/cytoplasmic ratios and dense, finely meshed nuclear chromatin. In addition, note the extrusion of delicate strands of cytoplasm from the outer cell membranes (blue arrow). These are cells connoting hairy cell leukemia (HCL). Under scanning electron microscopy, the cytoplasmic extensions appear to be either slender microvilli or delicate pseudopods. The most helpful confirmatory finding is the detection of acid phosphatase isoenzymne 5 in the cytoplasm of suspected hairy cells by staining. The enzyme concentrates primarily in golgi bodies and in the nuclear membrane and its staining is not inhibited by the addition of tartrate. Stated in another way, hairy cells on the peripheral smears are detected by their staining positively for tartrate-resistant acid phosphatase. Be suspicious of HCL if marrow resists aspiration-a consequence of reticulin fibrosis of the marrow in HCL.