Immunoglobulin G (IgG) is the most common antibody found in blood plasma, comprising 75-80% of all antibodies. IgG has four subtypes (IgG1, IgG2, IgG3, IgG4) and can cross the placental barrier to provide immunity to fetuses. It has properties like binding to pathogens to neutralize toxins and protect against infection. IgG deficiency can be caused by factors like aging or medications and leaves the body susceptible to infections like pneumonia or ear infections.

1. GROUP NO 1 . IMMUNOGLOBULIN G(Ig
G)
Objectives
1. Introduction
2. Sub-types/sub-classes
3. Properties
4. Functions/roles of Ig G
5. Deficit

2. Introduction
 Immunoglobulin G (Ig G) Is the most common and abundant antibody. Blood
plasma consists of 75-80% of Ig G antibodies
 It has longest life span of about 23 days, It can cross the placental barrier and
provide passive immunity to a developing fetus.
 Ig G antibodies remember the pathogens that have previously entered the body
and caused an infection

3. PROPERTIES
 It is the most versatile Ig and can carry all function of Ig molecules
 It is the major Ig in serum
 It is the only Ig that crosses placenta
 It is also found in extra-vascular space
 It fixes complement although not all sub classes do this well
 It binds to cells and is a good poisoning (substance that enhance phagocytosis)

4. SUB-CLASSES/TYPES
Ig G Is the combination of four different types which are IgG1, IgG2, IgG3 and IgG4
IgG1 Is the most abundant IgG sub-class in human sera, it mediates antibody
responses against viral pathogen
IgG2 it protect against protein antigens but responsible for anti carbohydrate IgG
responses against bacterial capsular polysaccharides.
 IgG3 it is known to promote inflammation as is associated with enhanced control
or protection against a range of intracellular bacteria, parasite and viruses.
 IgG4 It is believed to constitute a veritable antigen ‘garbage disposal’ system
which can attenuate inflammation.

6. FUNCTIONS/ ROLES
 It binds and neutralizes toxin
 It protect the body from infection
 It play an important role in antibody dependent cell mediated cytotoxicity
 Involved in regulation of allergic reaction

7. DEFICIT
 IgG deficiency is a health problem in which a body does not make enough
immunoglobulin G and predispose person to get infection
 IgG DEFICIENCY may be caused by aging, malnutrition, chemotherapy
medicines and long term corticosteroids

8. DEFICIT SYMPTOMS
 Ear infections
 Pneumonia
 Sore throat
 Bronchitis
 Gastrointestinal infection

9. GROUP MEMBERS
 Egon Moshi
 Asmaa Aboubakary
 Neema Augustine
 Lilian Emmanuel
 Salma Abdalah
 Sitta Malenya
 Michael Daudi
 Agape Piniel