1. Biochemistry Departement Medical Faculty Of Andalas University
BLOOD COMPOSITION
dr. Husnil Kadri, M.Kes
Biochemistry Departement
Medical Faculty Of Andalas University
Padang

2. BIOSINTESIS HEMOGLOBIN (PORFIRIN)

3. Struktur Porfirin
Porfirin adalah senyawa siklik yg dibentuk oleh 4 cincin pirol.
Masing-masing cincin dihubungkan oleh 4 jembatan metenil (-HC=).
Sifat khas porfirin adalah atom nitrogennya mampu mengikat ion logam.
Contoh;
- heme pada Hb mengikat Fe
- klorofil pada tumbuhan hijau mengikat Mg

4. Beberapa Hemoprotein Protein Fungsi
- Hemoglobin mengangkut oksigen di dalam darah
- Mioglobin menyimpan oksigen di dalam otot
- Sitokrom c keterlibatan pada rantai transpor elektron
- Sitokrom
P hidroksilasi xenobiotik
- Katalase degradasi hidrogen peroksida
- Triptofan
pirolase oksidasi triptofan

5. Sintesis Heme di Mitokondria
85% sintesis heme terjadi dalam sel pembentuk eritrosit pada sumsum tulang
Heme disintesis dari suksinil KoA + glisin.
Piridoksal fosfat diperlukan untuk mengaktifkan glisin.

6. Sintesis Heme di Mitokondria

7. Pengaturan Sintesis Heme
Enzim regulator adalah ALA-sintase.
Heme bertindak sebagai regulator negatif (umpan balik negatif) sintesis enzim ALA- sintase.
Jika heme meningkat, maka sintesis ALA-sintase akan menurun.

8. Porfiria Merupakan gangguan genetik biosintesis heme.
Umumnya autosomal dominan, kecuali porfiria eritropoitik kongenital.
Gejala;
- nyeri abdomen
- gangguan neuropsikiatri
- fotosensitifitas kulit
- bila berat = prototipe manusia srigala

9. Dasar Biokimia Porfiria
Mutasi DNA Abnormalitas enzim pada sintesis heme Akumulasi ALA & PBG atau Akumulasi porfirinogen penurunan heme dlm sel & di kulit & jaringan tubuh Cairan tubuh Tanda & gejala Oksidasi spontan porfirinogen neuropsikiatrik menjadi porfirin Fotosensitifitas

10. Terapi Porfiria Hanya simptomatik. Represor ALA-sintase; - glukosa
- hematin (bentuk hidroksida dari heme)
- b-karoten untuk fotosensitifitas
- preparat tabir surya
Kontraindikasi;
- preparat anestesi
- alkohol
- griseofulvin & barbiturat

11. Fungsi Utama Darah 1. Respirasi; pengangkutan O2 dan CO2 2. Nutrisi;
pengangkutan hasil absorpsi usus
3. Ekskresi;
pengangkutan sisa metabolik ke ginjal,
paru-paru, kulit, & usus

12. Fungsi Utama Darah 4. Keseimbangan asam-basa 5. Keseimbangan air;
antara sirkulasi darah dan jaringan
6. Pengaturan suhu tubuh
7. Pertahanan terhadap infeksi;
oleh sel darah putih & antibodi

13. Fungsi Utama Darah 8. Pengangkutan hormon & pengaturan metabolisme
9. Pengangkutan metabolit
10. Koagulasi

14. Components of Whole Blood
Plasma (55% of whole blood)
Buffy coat: leukocyctes and platelets (<1% of whole blood)
Formed elements
Erythrocytes (45% of whole blood) 1
Withdraw blood and place in tube 2
Centrifuge
Hematocrit
Males: 47% ± 5%
Females: 42% ± 5%

17. Physical Characteristics of Blood
Average volume of blood:
5–6 L for males; 4–5 L for females (Normovolemia)
Hypovolemia - low blood volume
Hypervolemia - high blood volume
Viscosity (thickness) (where water = 1)
The pH of blood is 7.35–7.45; x = 7.4
Osmolarity = 300 mOsm or 0.3 Osm
This value reflects the concentration of solutes in the plasma
Salinity = 0.85%
Reflects the concentration of NaCl in the blood
Temperature is 38C, slightly higher than “normal” body temperature
Blood accounts for approximately 8% of body weight

18. Components of Blood 55% plasma 45% cells 99% RBCs
< 1% WBCs and platelets

20. Blood Plasma Blood plasma components: Water = 90-92% Proteins = 6-8%
Organic nutrients – glucose, carbohydrates, amino acids
Electrolytes – sodium, potassium, calcium, chloride, bicarbonate
Nonprotein nitrogenous substances – lactic acid, urea, creatinine
Respiratory gases – oxygen and carbon dioxide

21. Formed Elements Formed elements comprise 45% of blood
Erythrocytes, leukocytes, and platelets make up the formed elements
Only WBCs are complete cells
RBCs have no nuclei or organelles, and platelets are just cell fragments
Most blood cells do not divide but are renewed by cells in bone marrow

22. Erythrocytes (RBCs) Biconcave disc
Folding increases surface area (30% more surface area)
Plasma membrane contains spectrin
Give erythrocytes their flexibility
Anucleate, no centrioles, no organelles
End result - no cell division
No mitochondria means they generate ATP anaerobically
Prevents consumption of O2 being transported
Filled with hemoglobin (Hb) - 97% of cell contents
Hb functions in gas transport
Hb + O HbO2 (oxyhemoglobin)
Most numerous of the formed elements
Females: 4.3–5.2 million cells/cubic millimeter
Males: 5.2–5.8 million cells/cubic millimeter

23. Erythrocytes (RBCs)
Figure 17.3

24. Erythrocyte Function
Erythrocytes are dedicated to respiratory gas transport
Hemoglobin reversibly binds with oxygen and most oxygen in the blood is bound to hemoglobin
Composition of hemoglobin
A protein called globin
made up of two alpha and two beta chains
A heme molecule
Each heme group bears an atom of iron, which can bind to one oxygen molecule
Each hemoglobin molecule thus can transport four molecules of oxygen

25. Structure of Hemoglobin
Figure 17.4

26. Hemoglobin Satu mol. Hb dewasa (HbA) mempunyai; - 4 gugus heme
- Setiap heme mengandung 1 ion Fe2+
- 4 subunit protein globin
- Setiap subunit mengikat 1 mol. O2
- 1 mol. Globin mengikat 1 mol. CO2
Subunit rantai terdiri dari 2 a dan 2 b;
- a masing-masing = 141 asam amino
- b masing-masing = 146 asam amino

27. Hemoglobin Oxyhemoglobin – hemoglobin bound to oxygen
Oxygen loading takes place in the lungs
Deoxyhemoglobin – hemoglobin after oxygen diffuses into tissues (reduced Hb)
Carbaminohemoglobin – hemoglobin bound to carbon dioxide
Carbon dioxide loading takes place in the tissues

28. WBC Anatomy and Types
All WBCs (leukocytes) have a nucleus and no hemoglobin
Granular or agranular classification based on presence of cytoplasmic granules made visible by staining
granulocytes are neutrophils, eosinophils or basophils
agranulocytes are monocyes or lymphocytes

29. Differential WBC Count
Detection of changes in numbers of circulating WBCs (percentages of each type)
indicates infection, poisoning, leukemia, chemotherapy, parasites or allergy reaction
Normal WBC counts
neutrophils 60-70% (up if bacterial infection)
lymphocyte 20-25% (up if viral infection)
monocytes % (up if fungal/viral infection)
eosinophil % (up if parasite or allergy reaction)
basophil <1% (up if allergy reaction or hypothyroid)

30. Neutrophils (Granulocyte)
Polymorphonuclear Leukocytes or Polys
Nuclei = 2 to 5 lobes connected by thin strands
older cells have more lobes
young cells called band cells because of horseshoe shaped nucleus (band)
Fine, pale lilac practically invisible granules
Diameter is microns
60 to 70% of circulating WBCs

31. Eosinophils (Granulocyte)
Nucleus with 2 or 3 lobes connected by a thin strand
Large, uniform-sized granules stain orange-red with acidic dyes
do not obscure the nucleus
Diameter is 10 to 12 microns
2 to 4% of circulating WBCs

32. Basophils (Granulocyte)
Large, dark purple, variable-sized granules stain with basic dyes
obscure the nucleus
Irregular, s-shaped, bilobed nuclei
Diameter is 8 to 10 microns
Less than 1% of circulating WBCs

33. Lymphocyte (Agranulocyte)
Dark, oval to round nucleus
Cytoplasm sky blue in color
amount varies from rim of blue to normal amount
Small cells microns in diameter
Large cells microns in diameter
increase in number during viral infections
20 to 25% of circulating WBCs

34. B cells responsible for production of antibodies
Lymphocytes
B cells - responsible for humoral immunity
T cells - responsible for cell mediated immunity
B cells responsible for production of antibodies
Receptor matches antigen
Cells multiply
Antibodies

35. T cells Cytotoxic T cells (Killer T cells) Helper T cells
Bind to cytotoxic cells (eg infected by virus)
Swell
Release toxins into cytoplasm
Helper T cells
Most numerous
Activate B cells, killer T cells
Stimulate macrophages
Suppressor T cells
Regulate activities of other cell types

36. Monocyte (Agranulocyte)
Nucleus is kidney or horse-shoe shaped
Largest WBC in circulating blood
does not remain in blood long before migrating to the tissues
differentiate into macrophages
fixed group found in specific tissues
alveolar macrophages in lungs
kupffer cells in liver
wandering group gathers at sites of infection
Diameter is microns
Cytoplasm is a foamy blue-gray
3 to 8% o circulating WBCs

37. Emigration & Phagocytosis in WBCs

38. UNSUR SELULAR DALAM RESPON IMUN
Jalur limfoid yang membentuk limfosit dan subsetnya
Jalur mieloid yang membentuk sel-sel fagosit mononuklear & polimorfonuklear (PMN).
PMN terdiri dari:
neutrofil, eosinofil, basofil

39. Platelets Platelets are fragments of mega-karyocytes
Their granules contain serotonin, Ca2+, enzymes, ADP, and platelet-derived growth factor (PDGF)
Platelets function in the clotting mechanism by forming a temporary plug that helps seal breaks in blood vessels
Platelets not involved in clotting are kept inactive by Nitric Oxide (NO) and prostaglandins

40. Protein Plasma
- Bagian utama unsur padat dalam plasma.
- Konsentrasi total protein plasma + 7-7,5 g/dl.
- Berbagai protein plasma dapat dipisahkan menurut karakteristik kelarutannya.
- Metode pemisahan tsb antara lain;
1. Salting-out (Na2SO4 23%, dll)
2. Elektroforesis

41. Zone Electrophoresis of Plasma Proteins- +
globulins
albumin g b a1 a2 pI
6.0
5.6
5.1
4.7

42. Protein Plasma
Sebagian besar disintesis di hepar.
Umumnya disintesis sbg preprotein pada poliribosom terikat membran. Preprotein akan mengalami modifikasi pascatranslasi.
Hampir semuanya berupa glikoprotein, kecuali albumin.
Bersifat polimorfisme (ciri bawaan pd populasi dgn sedikitnya 2 macam fenotipe).
contoh; gol. Darah ABO

43. Plasma Proteins
More than 200
Most abundant
Albumin g/100 mL
- g-globulins - ~1 g/100 mL
fibrinogen g/100 mL

44. Albumin
- Merupakan protein utama dalam plasma.
- Mempertahankan 75-80% tekanan osmotik.
- Berfungsi mengikat berbagai macam ligand,
seperti; asam lemak bebas, Ca, Cu, Zn,
hormon steroid, bilirubin, metheme

45. Albumin
- Albumin juga dapat mengikat obat-an,
seperti; sulfonamid, penisilin-G,
dikumarol, aspirin
- Penyakit hepar akan memperlihatkan rasio albumin/globulin yang menurun.

46. Transferin
Adalah b1-globulin berbentuk glikoprotein yang disintesis di hepar.
Berfungsi sebagai alat transpor besi (Fe3+) untuk dibawa ke jaringan.
Jika besi tidak diikat oleh transferin, maka akan menjadi prooksidan.

47. Ceruloplasmin
Protein ini adalah a2-globulin yang mengandung 90% Cu plasma.
Tetapi 10% Cu terikat longgar pd albumin, sehingga mudah dilepas ke jaringan.
Ceruloplasmin mengandung ferroksidase yang mengkatalisis ion Fe2+ --> Fe3+,
karena hanya ion Fe3+ yang mampu berikatan dgn apotransferin.

48. g-Globulins
20% of plasma proteins
“g” refers to electrophoretic mobility
Represents a group of proteins of variable structure
immunoglobulins
Main functional task is immunochemical
Antibodies - combine with specific antigens

49. Disintesis dalam sel plasma.
Imunoglobulin Plasma
Disintesis dalam sel plasma.
Sel plasma adalah turunan Sel-b yang mensintesis dan mensekresikan imuno- globulin sebagai respon terhadap pajanan berbagai antigen.
Semua imunoglobulin mengandung paling kurang 2 rantai ringan dan 2 rantai berat.

50. Classes of Immunoglobulins
IgG – Identifies microorganisms for engulfment or lysis
IgE – Inhibits parasite invasion; involved in allergic reactions
IgD – Unknown
IgA – Basis for passive immunity provided by breast milk, agglutinates infectious agents in secretions outside the body, present in tears, mucous
IgM – Identifies microorganisms for engulfment or lysis

51. Basic 4 chain structural unit
MW = 2x x27000 =
Constant - same amino acid sequence for all of the molecules
Variable - varies between molecules- results in specificity of molecules
Two heavy and two light chains joined by disulfide bonds. Variable region - red - binds the antigen Constant region (black) can activate complement pathway or attach the Ab to cells such as macrophages

52. The basic antibody unit is a monomer, IgA is a dimer and IgM is a pentamer

53. Fibrinogen
Coagulation
Structure: MW
Sequence of amino acids is known (3000)
4y, 3y structure
6 polypeptide chains, 2a (67,000), 2b (56,000), 2g (47,000)

54. Blood coagulation (clotting)
Function:
Blood coagulation (clotting)
Fibrinogen
Fibrin
Thrombin
Fibrin
Degradation (FDP)
Plasmin
Plasmin is end product of fibrinolytic system
Clot needs to be removed
Not needed forever
Could embolize to lungs, brain
Coagulation - very important consideration when processing blood outside of the body
Structure must incorporate the ability to be easily broken down after clotting
What is a clot and how does it form from the polymerization of fibrinogen?
Overhead from Brash’s notes next

55. Haptoglobin
Merupakan glikoprotein plasma yang mengikat hemoglobin ekstrakorpuskular.
Membentuk komplek Hb-Hp (Hemoglobin-Haptoglobin).
Hb ekstrakorpuskular merupakan hasil penguraian + 10% Hb yang dilepas ke dlm sirkulasi.

56. Kepustakaan
Marks, DB., Marks, AD., Smith CM Basic medical biochemistry: a clinical approach. Dalam: B.U. Pendit, penerjemah. Biokimia Kedokteran Dasar: Sebuah Pendekatan Klinis. Eds. J. Suyono., V. Sadikin., L.I. Mandera. Jakarta: EGC, 2000:
Murray, RK Porfirin dan pigmen empedu. Dalam: Andry Hartono, penerjemah. Harper’s Biochemistry. 25th ed. Eds. R.K. Murray, D.K. Granner, P.A. Mayes, V.W. Rodwell. McGraw-Hill Companies, New York:
Schumm, DE Essentials of biochemistry. Dalam: Moch. Sadikin, penerjemah. Intisari Biokimia. Jakarta: Bina Aksara, 1993: 147.

57. Kepustakaan
Harbut, C. 150 Blood. Download
Rand, ML., Murray, RK Protein plasma, imunoglobulin, dan pembekuan darah. Dalam: Andry Hartono, penerjemah. Harper’s Biochemistry. 25th ed. Eds. R.K. Murray, D.K. Granner, P.A. Mayes, V.W. Rodwell. McGraw-Hill Companies, New York:
Simpson, S. Chapter 19 Blood. Download
Sheardown, H. Blood Biochemistry. McMaster University. Download