Hematology and Immune System Overview

Hematology and Immune System

• This lecture covers the hematology and immune system
• The presenter, Dr. Nisreen Daffa Alla, has qualifications in M.B.B.S., PhD (Human Physiology), and MSc health Profession Education.
• References used include "Human Physiology" by Lauralee Sherwood (7th edition), "Textbook of Physiology" by Guyton & Hall (11th edition), "Textbook of Physiology" by Linda S. Contanzo (3rd edition), and "Physiology" by Berne and Levy (6th edition).

Plasma Proteins

• Plasma proteins make up 6% to 8% of plasma's total weight.
• There are 3 main groups of plasma proteins:
  • Albumins (most abundant):
    • 60% of plasma proteins
    • Major component of plasma osmotic pressure (80-90%)
    • Synthesized in the liver, with a half-life of 20 days (10-12g/day production)
    • Buffer pH
    • Decreased albumin (hypoalbuminaemia) leads to fluid leakage from the circulation, causing edema.
    • Causes include malnutrition, liver disease, and kidney disease.
  • Globulins (3 subclasses):
    • Synthesized in the liver or reticuloendothelial system
    • Alpha globulins transport water-insoluble substances (lipoproteins, lipids, hormones).
    • Beta globulins transport lipids, cholesterol, iron, and copper.
    • Gamma globulins (immunoglobulins) function as antibodies.
  • Fibrinogen:
    • Synthesized in the liver
    • Crucial for blood clot formation
    • Deficiency can cause excessive bleeding.

Plasma Protein Concentrations (Average)

• Albumin: 4.8 g/100ml
• Globulins: 2.3 g/100ml
• Fibrinogen: 0.3 g/100ml
• Total: 7.4 g/100ml

Plasma Protein Functions

Plasma Electrolytes

• Major plasma electrolytes include Na+, K+, Cl–, and HCO3–.
• Functions:
  • Maintain membrane potentials
  • Control osmotic distribution of fluids between ECF and ICF
  • Buffer pH changes

Blood Composition

• Blood accounts for approximately 8% of total body weight.
• Average volume:
  • 5 liters in women
  • 5.5 liters in men
• Composed of two parts: plasma (liquid) and cellular elements.

Cellular Elements

• Erythrocytes (red blood cells): most numerous; transport O2, CO2, and buffer hydrogen ions.
• Leukocytes (white blood cells): crucial for immunity.
• Thrombocytes (platelets): vital for hemostasis (blood clotting).

Hematocrit/Packed Cell Volume (PCV)

• Hematocrit (PCV) represents the percentage of erythrocytes in the total blood volume.
• Average PCV is 45% in men and 42% in women

Blood Centrifugation

• Separates blood into plasma (55%), buffy coat (<1%) and RBCs (45%)

Blood Functions

• Transport: respiratory gases (O2 & CO2), nutrients, metabolites, hormones, drugs, and enzymes.
• Defense against infections.
• Regulation of homeostasis: body temperature, acid-base balance, and fluid and electrolyte balance.

Objectives of the Lecture

• Describe blood composition
• List plasma proteins
• Explain plasma protein functions
• Relate plasma protein changes to clinical conditions

Case Study (Patient)

• 55-year-old male with new-onset ascites and lower extremity edema
• Moderate alcohol consumption; jaundice
• Mild abdominal tenderness; no organomegaly
• Lower-extremity edema to mid-calf
• Pedal pulses barely palpable
• Investigations include abnormal BUN, creatinine, AST, ALT, serum albumin, platelets, sodium, potassium, alkaline phosphatase, and total bilirubin levels.

The Patient's Diagnosis and Questions

• Diagnosed with liver failure
• Questions posed regarding the cause and development of edema in the patient.

Case Study - Fibrinogen Deficiency

• Congenital absence of fibrinogen (fibrinogenemia) will present with excessive bleeding.

Revision Questions

• Mention blood components
• Identify the most numerous blood cell
• List three plasma proteins and their functions
• Detail the site of synthesis and function of albumin, alpha and beta globulin, and gamma globulin .

This quiz provides insights into the hematology and immune system, focusing on plasma proteins and their functions within the human body. Presented by Dr. Nisreen Daffa Alla, it draws from several authoritative textbooks in human physiology. Test your understanding of the essential components and roles of plasma proteins and their implications in health.