FACTORS INFLUENCING THE PREIMMUNE ANTIBODY REPERTOIRE

Preimmune antibody repertoire is not a statistical representation of a ll germ-line V-H, D, J(H) and V-L, J(L) segments encoding heavy and li ght chains, respectively. The antibody repertoire is biased towards a fraction of V-H and V-L gene segments in fetal/neonatal as well as adu lt life. The repertoire bias starts at the surface Ig-negative pre-B c ells and persists throughout B-cell ontogeny. Antigen-independent proc esses like preferential rearrangements of V-H, D and J(H) segments and pairing of the heavy and surrogate light chain operate at the surface Ig-negative pre-B cell stage. Subsequently B cells may be subject to self-antigen selection based on the specificity of their surface recep tors.