Specimen Nr. 05A


Spleen (Rat), passing T lymphocytes


Alkaline-phosphatase technique, nucleus stained with hemalaun



Important structures :

1.Periarteriolar lymphoid sheath (PALS)
2.Central artery
3.Secondary lymphoid follicle with germinal centre
4.Marginal zone of white pulp
5.Red pulp
Mit einem Antikörper sind immunhistochemisch in blau T-Lymphozyten dargestellt, die 24 Stunden zuvor intravenös verabreicht wurden. Es wurden der Ratte 20 x106 Zellen gespritzt, was etwa einem Viertel der sich im Blut der Ratte befindenden T-Lymphozyten entspricht. Die T-Lymphozyten sind 24 Stunden nach der Injektion vor allem in der PALS zu finden.


Periarteriolar lymphoid sheath (PALS)
Central artery
Secondary lymphoid follicle with germinal centre
Marginal zone of white pulp
Red pulp

Localisation of organs of immune-lymphatic system[we]

1. Pharyngeal tonsil
2. Palatine tonsil
3. Lymph node
4. Lymphatic vessels
5. Spleen
6. Peyer's patches
7. Thymus


Immunohistochemistry is used to confirm the presence of or to identify certain structures or substances in tissue sections which cannot be identified with conventional staining methods. Such structures include: cells, enzymes, hormones, macromolecules like nucleic acids and polysaccharides. The basis of immunohistochemical staining techniques is the antigen-antibody reaction. This method makes it possible to differentiate, for example, various cells in a tissue section according to their different metabolic products or surfaces. Either the metabolic product or a certain surface component serves as the antigen. In the first step, the antigen reacts with a specific antibody. The resulting antigen-antibody complex is invisible. Therefore, in a further step a second antibody bound to an adjuvant is added and binds to the initial antibody (so-called sandwich procedure). The bound adjuvant makes the antigen-antibody complex visible under the microscope and identifies the sought structure. Adjuvants are:

Combination with further dyes or staining techniques:

T-Lymphozyten gelangen auch über die Marginalzone in die Milz. Einen Tag nach Injektion haben sie dieses Kompartiment verlassen und befinden sich überwiegend in der PALS. Dieses Präparat macht deutlich, daß ein histologischer Schnitt einer Milz nur die Momentaufnahme eines dynamischen Geschehens darstellt. Täglich wandern mehr Lymphozyten in die Milz ein und wieder aus, als in jedes andere Organ des Körpers.







Periarteriolar lymphoid sheath (PALS)
Central artery
Secondary lymphoid follicle with germinal centre
Marginal zone of white pulp
Red pulp
Red pulp
Red pulp

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