The Coordinated Response to Infection

Question 1

How are B Cells helped by T cells in a polysaccharide vaccine?

Answer 1

• Vaccines prepared from purified polysaccharides generate poor responses in those under 2 years of age as well as very little isotype switching and poor memory because T and B cell receptors recognise different epitopes - T cells interact with peptide antigens
• We can chemically connect a protein antigen to a polysaccharide antigen
• The T cell can react with peptides from the protein and provide help for B cells
• If the BCR/membrane Ig binds with the polysaccharide, anti-polysaccharide antibodies can be produced.