ILS 3: Human cells, tissues, & Histology

Hematoxylin & Eosin [H&E]

hematoxylin

• basic dye that stains acidic structures purple/blue

• basophilic structures [DNA, RNA, RER]

eosin

• counterstain that stains basic structures

• eosinophilic structures [cytoplasm]

general morphology, routine biopsy

Periodic Acid-Schiff [PAS]

• detects structures rich in polysaccharides

• stain red/purple

• glycogen storage disease

  • identify glycogen storage deposits in liver

Masson’s trichome

highlights collagen, used to determine fibrosis

Giemsa stain

• stains chromatin & nuclear membranes blue/purple

• cytoplasmic components pink/red

• used to diagnose malaria, blood parasites, stain blood smears

Human cell has high ECF concentration of these

Sodium [Na] - most

Calcium [Ca]

Chloride [Cl]

Human cell has high ICF concentration of these

Potassium [K] - most

Mg, sulphates, phosphates, & proteins

Peroxisome

• has oxidases & catalase

  • destroy free radicals

• detox alcohol → acetaldehyde in liver cells

• catabolize long chain fatty acids

loose connective tissue

• large amount of ground substance

  • secreted by fibroblasts

dense connnective tissue

smaller amount of ground substance

Granulocytes

Neutrophils

Eosinophils

Basophils

Agranulocytes

Lymphocytes

Monocytes

Visually differentiate the diff WBC types

Neutrophils

• recognize & digest foreign particles/bacteria

• 40-60%

Eosinophils

• active against blood parasites & allergies

• 1-6%

Basophils

• hypersensitive (allergic) reactions

• <1%

Lymphocytes

B cells

• antibodies

• cell-mediated immunity

T cells

• recruit other immune cells & attack viral-infected cells

• humoral-immunity

• 20-40%

Monocytes

• macrophages in tissues

• phagocytosis - cell debris, apoptotic cells, microorganisms

• 2-8%