孔 力

Human Histology

Histology and Embryology Department

Introduction

1.   Goal of Histology Histology is the study of the tissue of

the body and of how these tissues are arranged to constitute organs.

Cell:Tissue: made of cells and extracellular

matrix Basic tissue: Basic tissue: Epithelium Connective tissue Muscle tissue Nerve tissue

cells and extracellular matrix

Tissue:

Organ:

systems :

2. Relationship between histology and other medicine courses

EpitheliumConnective tissue Muscle tissueNerve tissue

3. Histologic methods3-1. microscopy/ 显微镜 Fine structure

light microscopy: (LM) resolution—0.2um 1um ＝ 10 － 3mm ＝ 10 － 6m

H.E. Staining ( H: Hematoxylin E : Eosin ) basophilic,

acidophilic

激光共聚焦扫描显微镜

（ confocal laser scanning microscope ）

激光共聚焦扫描图像

Electronmicroscopy (EM) : ultra structure

resolution---0.2nm / 1um=1000nm

scanning EM transmission EM

Histochemistry and Cytochemistry

Photomicrograph of an intestinal villus stained by PAS. Staining is intense in the cell surface brush border (arrows) and in the secretory product of goblet cells (G) because of their high content of polysaccharides. The counterstain was hematoxylin.

3-2 Specific Localisation Methods for LM and EM

过碘酸－ Schiff 反应：（ periodic acid Schiff reaction ， PAS 反应）

过碘酸 糖－乙二醇基 糖－乙二醛基

Schiff 试剂

（亚硫酸品红）

不溶性紫红色反应产物（ PAS 反应阳性）

Immunohistochemistry, Immunocytochemistry

(1) Molecule A has a high and specific affinity toward a portion of molecule B. (2) When A and B are mixed, A binds to the portion of B it recognizes. (3) Molecule A may be tagged with a label that can be visualized with a light or electron microscope. The label can be a fluorescent compound, an enzyme such as peroxidase, a gold particle, or a radioactive atom. (4) If molecule B is present in a cell or extracellular matrix that is incubated with labeled molecule A, molecule B can be detected.

3-3 Cell and Tissue Culture

Cultured neural crest cells seen with different optical techniques. The cells are unstained, and the same cells appear in all photographs. Use the two pigmented cells for orientation in each image. A: Conventional light microscopy. B: Phase contrast microscopy. C: Nomarski differential interference microscopy.

组织工程（ tissue engineering ）

我国第一个组织工程产品——组织工程皮肤

3-4 Hybridization Techniques In situ Hybridization 原位杂交

Tissue section of a benign epithelial tumor (condyloma) submitted to in situ hybridization. The brown areas are places where DNA of human papillomavirus type 2 is present. The counterstain was hematoxylin.

4. Problems in the interpretation of tissue section

How different 3-dimensional structures may appear when thin-sectioned. A: Different sections through a hollow ball and a hollow tube. B: A section through a single coiled tube may appear as sections of many separate tubes. C: Sections through a solid ball (above) and sections through a solid cylinder (below).