The largest and most important cells, often attached to collagen fibers

The cells of those with active functions are larger and have many processes; the nuclei are large, oval, light-colored, and have obvious nucleoli; the cytoplasm is rich and weakly basophilic.

The cells synthesize and secrete collagen and elastin and form an amorphous matrix

When in a resting state, they are called fiber cells. The cells are small, long spindle-shaped, with small and elongated nuclei, dark staining, and less eosinophilic cytoplasm.

A type of immune cell widely present in the body, derived from monocytes in the blood

Those with active functions often extend long pseudopods and have irregular shapes. The nuclei are small, round or renal, and deeply stained. The cytoplasm is rich, mostly eosinophilic, and may contain foreign particles and vacuoles.

When in a resting state, they are called tissue cells. When stimulated by chemokines, the cells are activated and move toward the site where the factors are released. This is chemotaxis.

immune response involved

Mainly distributed in connective tissue or chronic inflammation sites of spleen, lymph nodes and mucous membranes

Oval or round, the nucleus is round or ovoid, mostly on one side, and there is a light staining area (LM) next to the nucleus; heterochromatin is often in the shape of thick strips, radiating from the center of the nucleus to the nuclear membrane. Distribution (wheel-shaped) (EM), abundant cytoplasm, basophilic

Synthesizes and secretes immunoglobulins (antibodies)

Hematopoietic progenitor cells derived from bone marrow are often distributed along small blood vessels and lymphatic vessels, and are more abundant in mucosal connective tissues.

The cells are larger, round or oval, with a small, round, central nucleus; the cytoplasm is filled with thick basophilic secretory granules, which can be stained purple by aldehyde-fuchsin.

Can initiate an inflammatory response against pathogens by releasing a variety of active substances: histamine, leukotrienes. These two substances can dilate local blood vessels, enhance permeability, increase tissue fluid leakage, and cause local edema; chemokines allow immune cells to enter connective tissue for sterilization

allergy

The cell body is large, spherical or polygonal; it contains a large lipid droplet that squeezes the rest of the cytoplasm and nucleus to the cell periphery.

In HE-stained specimens, lipid droplets are dissolved and cells appear vacuolated.

Can synthesize and store fat and participate in lipid metabolism

Stem cells, mostly distributed around small blood vessels, resemble fibroblasts in shape

It can proliferate in large quantities during inflammation and wound repair, and can differentiate into fibroblasts, etc.

Eosinophilic in HE stained sections, usually present in bundles

The biochemical component is type I collagen.

Collagen is secreted by fibroblasts, polymerizes with extracellular cells to form collagen fibrils, and then forms collagen fibers with a small amount of adhesive.

High toughness and strong tensile strength

It is light red in HE-stained sections and purple in aldehyde-fuchsin staining.

Contains less collagen fibers, but is widely distributed

The core is composed of homogeneous amorphous elastin and the periphery is covered with microfibrils

Elastin molecules are extensively cross-linked by covalent bonds to form a network that can be bent at will; strong sunlight can break the elastic fibers in the skin, causing wrinkles on the skin.

Mainly composed of type III collagen

It appears light red in HE stained sections and black in silver stained sections.

Mainly distributed in reticular tissue, reticular plate of basement membrane, acini, and around capillaries

Polymers formed by covalent bonds between aminoglycans and proteins

Hyaluronic acid among the non-sulfated aminoglycans forms the backbone of proteoglycans

A large number of proteoglycan aggregates form a molecular sieve with many micropores, which only allows small molecules of nutrients to pass through, while large molecules and bacteria cannot pass through, forming a barrier that limits the spread of harmful substances.

Hemolytic streptococci and cancer cells can produce hyaluronidase, which can destroy the matrix structure and therefore can spread and metastasize.

The main adhesive glycoprotein of connective tissue matrix

There are binding sites for a variety of cells, collagen, and proteoglycans on the surface, forming an integrated collagen fiber network structure, thus affecting cell adhesion, migration, tumor metastasis, embryonic development, growth, and differentiation.

Water-soluble small molecules penetrate into the matrix from the blood vessel wall at the arterial end of the capillary to form tissue fluid; most of it returns to the blood from the venous end of the capillary, and a small part enters the lymphatic capillary to form lymph, and finally returns to the blood

Tissue fluid is dynamically updated