4-26 Connective tissue

A blood count of a healthy person reveals that the neutrophils are the most numerous cells among the leukocytes (the leukocytes are also called white blood cells). An analysis of tissue sectons with a light microscope shows that leukocites are always found in small amounts in connective tissues. Their lifespan in this tissue is usually short (about 12 hours) and they are constantly being replaced by new neutrophils that arrive from the blood.
Neutrophils are formed in the hematopoietic marrow from precursor cells and undergo several stages during their development. In one of the last stages, they are classified as young neutrophils
and are also called band cells (or simply “bands”). Their nucleus begins to display a shape similar to that of the letter “C”.
Most neutrophils that are at the stage of band cells continue their development, and one of the most notable features of the final stage of development is the appearance of nuclear lobes. The nucleus, previously shaped like a letter “C”, is seen as two or more portions joined by thin bridges of chromatin strands. Each of these fragments is a nuclear lobe. Neutrophils with lobulated nuclei are also called called “segmented neutrophils” or adult neutrophiles¨”. They are the predominant form of leukocytes in the circulating blood. Rod-shaped cells are also present in small numbers in normal circulating blood.
After placing the cursor or clicking on the figure, observe:
Segmented neutrophils – in red. The best way to recognize and diagnose neutrophils is to observe two or more small portions of chromatin in the cytoplasm, the nuclear lobes. Their cytoplasm is lightly stained.
Plasmocytes are oval cells with an excentric eccentric non-lobulated nucleus containing clumps of chromatin, and a basophilic cytoplasm.In the image they become highlited in green after olacing the cursor over the image ou clicking on the image.
Some of the large cells in the image with spherical nuclei and slightly “foamy” cytoplasm have features of macrophages.They become highligted in blue when using the mouse or clicking on the image.