Where is it? Primary lymphoid Secondary lymphoid organs organs Tonsils and adenoids Thymus Spleen Peyers patches Appendix Bone marrow Lymph nodes Lymphatic vess∈
Where is it? Lymphatic vessels Lymph nodes Thymus Spleen Tonsils and adenoids Bone marrow Appendix Peyer’s patches Primary lymphoid organs Secondary lymphoid organs
Multiple layers of the immune system --·--·- Pathogens Skin Biochemical barriers Phagocyte Innate Immune response Lymphocytes Adaptive Immune ○E response
Multiple layers of the immune system Phagocyte Adaptive immune response Lymphocytes Innate immune response Biochemical barriers Skin Pathogens
Immune Pattern recognition BCR or Antibody B-cell Receptors(Ab) Epitopes Antigen B-cell o60 x The immune recognition is based on the complementarity between the binding region of the receptor and a portion of the antigen called epitope Antibodies present a single type of receptor, antigens might present several epitopes This means that different antibodies can recognize a single antigen
Immune Pattern Recognition The immune recognition is based on the complementarity between the binding region of the receptor and a portion of the antigen called epitope. Antibodies present a single type of receptor, antigens might present several epitopes. This means that different antibodies can recognize a single antigen B-cell BCR or Antibody Epitopes B-cell Receptors (Ab) Antigen
Antibodies →-4--4--1---1---4--4-- Antigen binding sites 几 Gene rearrangement Rearranged DNA Fab CL CL/ Fab Transcription RNA c F Heavy chain of an immunoglobulin Antibody molecule antibody production
Antibodies Antigen binding sites VH VL CH CH VL CL CH VH CH CL Fc Fab Fab Antibody Molecule ... ... ... V V D D J J C Gene rearrangement Rearranged DNA V D J C Transcription RNA V D J C Splicing mRNA V D J C Translation Heavy chain of an immunoglobulin Antibody Production
Clonal selection Clonal deletion Self-antigen Proliferation Selection Memory cells Differentiation Plasma cells ign antigens Self-antigen Clonal deletion (negative selection)
Clonal Selection Foreign antigens Proliferation (Cloning) Differentiation Plasma cells Memory cells Selection M M Antibody Self-antigen Self-antigen Clonal deletion (negative selection) Clonal deletion (negative selection)