1. BLOOD BLOOD IS A CONNECTIVE TISSUE WITH TROPHIC FUNCTION
ITS INTERSTITIAL TISSUE IS A FLUID NAMED PLASMA
COMPOSITION: Albumin (60%)
Globulines (35%)
Fibrinogen (4%)
Electrolytes (Na+, K+, Ca2+, Mg2+, etc.) Catabolytes (urea, uric acid, creatinin) Nutrients (glucose, lipids, amino acids, vitamins)
Gasses (oxigen,carbonic anhidride, natrium)
HORMONES
CELLS AND PLATLETS CONSTITUTE 45% OF THE BLOOD VOLUME
ERITROCYTES: 4-6 x 106/mm3
LEUCOCYTES: /mm3
GRANULOCYTES: NEUTROPHILES: 50-70%
EOSINOPHILES: 2-5%
BASOPHILES: 0.5-1%
LINFOCYTES: 20-40%
MONOCYTES: 2-10%
PLATLETS: /mm3

2. HAEMATOCRIT OR PCV (Packed Cell Volume)

3. PLASMA & SERUM
Plasma is the liquid phase of the blood containing all of the
soluble components including the coaugulation factors. It is
separated by the cell elements allowing their sedimentation
following the addition of anticoaugulants (citrate, heparin, EDTA).
Serum is the liquid phase of the blood devoid of the coaugulation
factors. It is obtained allowing coaugulation of the blood sample
followed by centrifugation or waiting for contraction of the clot.

4. RED BLOOD CELLS ANUCLEATED BICONCAVE DISCS (7-8 micrometers diameter)
HALF LIFE OF 120 DAYS
LOADED OF HOEMOGLOBIN
PRODUCED IN MYELOID TISSUE (in the bone morrow)
DEGRADED IN THE SPLEEN

5. RED BLOOD CELLS
Erythrocytes enmeshed in filaments of fibrin in a clot.

6. RED BLOOD CELLS
A human heart muscle biopsy specimen, showing an erythrocyte
within a capillary. The erythrocyte biconcave disc is typically electron dense and almost fills the capillary lumen.

7. GRANULOCYTES

8. GRANULOCYTE FUNCTIONS
NEUTROPHILES: Mainly phagocytosis
EOSINOPHILES: Antihistaminic action, phagocytosis
of antigene-antobody complexes,
foreign proteins digestion
BASOPHILES: Release of histamine and heparin under
IgE stimulation, triglyceride digestion
following fat ingestion

9. MONOCYTES

10. MONOCYTE FUNCTIONS PHAGOCYTOSIS
PRECURSOR OF: CONNECTIVE TISSUE MACROPHAGES
OSTEOCLAST
KUPFER CELLS
INVOLVED IN INNATE IMMUNITY AND IN THE PRESENTATION
OF ANTIGENS TO THE IMMUNE COMPETENT CELLS

12. GRANULOCYTES
Neutrophil and basophil granulocytes within a renal glomerular capillary in a human kidney biopsy. The neutrophil nucleus is more segmented (four lobes are visible) and the granules are smaller and more electron-dense than in the basophil.

13. Haemopoietic tissue in the marrow cavity of a fetal long bone undergoing endochondral ossifi cation (top). Islands of densely packed nucleated haemopoietic cells of different lineages are separated by large vascular sinusoids which are filled with mature red blood cells in the general circulation.

14. Bone marrow sample taken from the human posterior iliac crest
Bone marrow sample taken from the human posterior iliac crest. Bone marrow haemopoietic and adipose tissue (haematoxylin and eosin stain)

16. LYMPHOCYTES LYMPHOCYTE FORMULA
T LYMPHOCYTES: 70-80% (Cell Mediated Immunity)
B LYMPHOCYTES: 5-15% (Humoral Immunity)
NK LYIMPHOCYTES (NaturalKiller): 5-15% (Cell Mediated response)

17. LYMPHOCYTES A small, resting lymphocyte in human peripheral blood. The
nuclear/cytoplasmic ratio is high and the cytoplasm contains few
organelles, indicative of its quiescent state.

18. LYMPHOCYTES
A mature B cell (plasma cell) in human connective tissue. The abundant rough endoplasmic reticulum is typical of a cell actively synthesizing secretory protein, in this case immunoglobulin. The cell to the left is a fibroblast.

19. LYMPHOID TISSUE SITE OF LYMPHOCYTE PRODUCTION AND STORAGE
PRIMARY: TYMUS, BONE MORROW. Site of lymphocyte production starting from stem cells.
SECONDARY: SPLEEN, LYMPH-NODES, MALT (Mucosa-Associated LymphoidTissue), TONSILS (Pharyngeal), PEYER plaques in the intestin

20. Lymph node (human) sectioned mainly through cortical tissue, showing lymphoid follicles, some with germinal centres, and connective tissue trabeculae. Also shown is the subcapsular sinus and hilum with blood vessels.
A germinal centre in a human tonsil lymphoid follicle, immunolabelled to show CD 38-positive B cells in the germinal centre (red), IgD-positive naïve B cells (green) in the mantle zone and activated,
transferrin receptor (CD 71)-positive cells of various lineages (blue).

21. Germinal centre in a follicle of mucosa-associated lymphoid tissue (MALT) in the mucosa and submucosa of the appendix. The bases of tubular glands of the mucosal epithelium are
Seen on the left.

22. LYMPH
YELLOW FLUID SIMILAR TO PLASMA CONTAINING SOLUTES AND CELLS DERIVING FROM THE CONNECTIVE TISSUE
COLLECTED IN THE INTERSTITIAL TISSUE BY LYMPH CAPILLARIES
THEY REACH LYMPHATIC VESSELS THAT PASS THROUGH LYMPH-NODES WHERE THE LYMPH IS FILTERED.
LYMPHATIC VESSELS REACH THE BLOOD VESSELS WHERE THE LYMPH ENTERS.

24. IMMUNE SYSTEM ANTIGEN: ELEMENTS EXTRANEOUS TO THE BODY
Soluble toxines (e.g.: tetanus, viral proteis)
Membrane components of microorganisms
ANTIGEN RECOGNITION: (LYMPHOCYTES, MACROPHAGES, ANTIGEN PRESENTING CELLS LIKE DENDRITIC CELLS (Langerhans)
NEUTRALYZATION OF THE ANTIGENS IS THEN PERFORMED IN DIFFERENT WAYS BY LYMPHOCYTES (cell distruction, specific antibodies secretion.

26. Alveolar macrophages (dust cells, arrows) containing ingested carbon particles, in alveoli and interalveolar septa of the human lung.