Unknown? 2004/04/23
The occurrence of blood cells is a continuous development process, and the development of various blood cells can be roughly divided into three stages: primitive stage, naive stage (divided into early, middle and late stages) and mature stage. Bone marrow smear examination is an important basis for the diagnosis of hematological diseases.
The general rules of morphological changes during hematopoiesis are as follows: ① Cell body changes from big to small, and megakaryocyte changes from small to big. (2) The nucleus changes from big to small, the erythrocyte nucleus eventually disappears, the granulocyte nucleus gradually changes from round to rod or even leaves, and the megakaryocyte nucleus changes from small to big and leaves; The chromatin in the nucleus gradually became thicker and denser, and the nucleoli gradually disappeared from the obvious; The color of the nucleus changes from light to dark. ③ The amount of cytoplasm gradually increased from less to more, and the basophilicity of cytoplasm gradually weakened, but monocytes and lymphocytes remained basophilic; The special structures in cytoplasm, such as hemoglobin in red blood cells and special particles in granulocytes, are from scratch and gradually increase. ④ The ability of cell division is from existence to non-existence, but lymphocytes still have strong potential division ability.
1. Erythropoiesis goes through pre-erythropoiesis, early erythropoiesis (or basophilic erythropoiesis), middle erythropoiesis (or polychromatic erythropoiesis) and late erythropoiesis (or normal erythropoiesis), and the latter is denucleated and becomes reticulocyte. It takes about 3 ~ 4 days to develop from protoerythrocytes to advanced erythrocytes. Macrophages can devour the nuclei and other metabolites of late red blood cells and provide iron and other nutrients for the development of red blood cells. The general morphological characteristics of cells in each stage are shown in Table 5- 1 (Figure 5- 1 1).
Table 5- 1 Morphological evolution of erythropoiesis
Development stage and cell body name
Size and shape
(micron)
nucleus
Nucleolar-cytoplasmic ratio of shape chromatin
cytoplasm
Division ability of basophilic hemoglobin
Primitive red blood cell
Young early red blood cells
Young red blood cells
Late erythrocytes
stage
success
Mature reticulocyte
Ladder red blood cell
stage
14 ~ 22 yuan
1 1 ~ 19 cycles
10 ~ 14 circle
9 ~ 12 circle
7 ~ 9 disc shape
7 disc shape
Round and fine grained 2 ~ 3 >: 3/4
Accidental roundness and roughness >: 1/2
The round block disappears about 1/2.
Circular compactness disappears less.
not have
not have
Strong? Dark blue is nothing.
A strong dark blue color began to appear.
Reduce polychromatic activity and slightly increase.
Red and blue dyes?
Pale red Many of them don't.
Micro? Red? Many of them don't.
Nothing? Red? Many of them don't.
2. Granulogenesis Granulogenesis has gone through the processes of myeloblast, promyelocytic, mesoblastic, and late promyelocytic, and then differentiated into mature rod-shaped nuclei and lobulated granulocytes. It takes about 4 ~ 6 days to differentiate from granulocyte to promyelocytic. The storage of rod-shaped granulocytes and lobulated granulocytes in bone marrow is very large, and they are released into the blood after staying in bone marrow for 4 ~ 5 days. If the release of bone marrow is accelerated, the number of granulocytes in peripheral blood can suddenly increase. See Table 5-2 for the general morphological characteristics of cells at each stage (Figure-1 1).
3. Monocyte proliferation Monocytes are transformed into monocytes by monocytes and pre-monocytes (Figure 5- 13). Young monocytes have strong proliferative ability, about 38% of them are in a proliferative state, and the storage of monocytes in bone marrow is less than that of granulocytes. When the body has inflammation or active immune function, young monocytes accelerate division and proliferation, providing enough monocytes.
4. Megakaryocyte develops into megakaryocyte through pre-megakaryocyte, and the cytoplasm of megakaryocyte falls off and becomes platelet (Figure 5- 1 1). Protomegakaryocytes differentiate into young megakaryocytes, which become larger in size, with kidney-shaped nuclei and fine particles in cytoplasm. The nucleus of young megakaryocytes divides several times, but the cell body does not divide, forming megakaryocytes. Megakaryocytes are irregular, with a diameter of 40 ~ 70μ m or even larger, and their nuclei are lobulated. There are many platelet granules in the cytoplasm, and there are many reticular tubules formed by smooth endoplasmic reticulum, which divide the cytoplasm into many cells, and each cell is a future platelet with granules. It can also be seen that the megakaryocyte extends out of the slender cytoplasmic process and extends into the sinus cavity along the blood sinus wall, and its cytoplasmic end expands and falls off to form platelets (Figure 5- 12). Each megakaryocyte can produce about 2000 platelets.
Fig. 5- 12 Electron microscopic image of human megakaryocyte (above) ×45000.
1 .nuclear 2. Platelet granule 3. Smooth endoplasmic reticulum
(Photo courtesy of Professor Yin Xin and Professor Shi Xiuxiong from Bethune Medical University)
Here, the cytoplasm of a small macrophage falls off and enters the blood sinus.
Table 5-2 Morphological Evolution of Particles
Hairdressing education
Stage and name
body
Size and shape
(micron)
nucleus
Shape chromatin nucleoli
proportion
cytoplasm
Basophilic coloring, special for azure? divide
Particle capacity
Primitive granulocyte
promyelocyte
Juvenile granulocyte
Advanced promyelocytic granulocyte
stage
success
boil