Image Based Question-65739

Identify the Antigen-Antibody reaction in the figure shown in which Lattice hypothesis is used to explain the basis of this reaction .

A. Precipitation.

B. Opsonization.

C. Complement fixation.

D. Neutralization.

Correct Answer » A Explanation

Ans:A. Precipitation

Lattice hypothesis is used to explain the basis of Precipitation.

Precipitation Antigen-Antibody reaction

Marrack (1934) proposed the lattice hypothesis – mechanism of precipitation.

• Precipitation reactions are based on the interaction of antibodies and antigens. They are based on two soluble reactants that come together to make one insoluble product, the precipitate . These reactions depend on the formation of lattices (cross-links) when antigen and antibody exist in optimal proportions.

Precipitation curve shows 3 curves:

1. Zone of Antibody excess
2. Zone of Equivalence
3. Zone of Antigen excess

Antigen-antibody reaction

• It is a specific chemical interaction between antibodies produced by B cells of the white blood cells and antigens during immune reaction.

Types of antigen- antibody reactions in vivo:

1. Agglutination
2. Precipitation
3. Complement fixation
4. Neutralization
5. Antibody dependant cell mediated cytotoxicity (ADCC)
6. Immobilization

Types of antigen antibody reactions used in vitro:

1. Agglutination
2. Precipitation
3. Neutralization
4. Complement fixation
5. Fluorescent Fluorescent-antibody technique antibody technique
6. ELISA- Enzyme linked immunosorbent Enzyme linked immunosorbent assay
7. Radio immunoassay
8. Immunochromatography (ICT)