A Caltech Library Service

An Analysis of Patterns of Diversity in Antibodies with Defined Specificity


Johnson, Nelson Daniell (1981) An Analysis of Patterns of Diversity in Antibodies with Defined Specificity. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/1wj1-r628.


Antibodies can recognize a large number of molecular determinants (antigens) because of the diversity present in antibody combining sites. This diversity resides in regions of extensive amino acid variability termed variable (V) regions. Variable region diversity is encoded in multiple germline variable region genes and can also arise from somatic modification of these genes. An important class of somatic modifications is the rearrangement of gene segments to form complete variable region genes. In this way complete VL genes arise from the joining of VL and JL gene segments while VH genes arise from VH, D, and JH gene segment joining.

Studies of the V region protein sequences of hybridoma and myeloma immunoglobulins which bind phosphorylcholine show that IgM antibody V regions are considerably less diverse than IgG and IgA V regions. A comparison of protein sequence data with experiments on germline DNA suggests that at least some V segment diversity in IgG and IgA antibodies is the result of somatic mutations. D segments from phosphorylcholine-binding IgM antibodies as well as from IgG and IgA antibodies show extensive amino acid interchanges and size differences. In addition, diversity in the antibody response to phosphorylcholine is generated by associating a single VH region with at least two different VL regions.

The complete sequences of the V L and V H regions from two antibodies binding β (2 → 1) levan have also been determined. A comparison of these sequences to protein sequence data from other β (2 → 1)) levan-binding proteins and to a germline DNA sequence suggests that the levan-binding proteins may arise from multiple germline genes differing at the protein level by only a few amino acids. Unlike the D segments of the phosphorylcholine binding proteins, the levan-binding immunoglobulin D segments show very little diversity. In addition, the protein sequences of levan-binding immunoglobulins can be compared to published V region idiotype and antigen binding studies. These comparisons show that idiotypes may focus on certain sections of antibody V regions, and hence be of limited value as a probe of antibody V region fine structure.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:Biochemistry
Degree Grantor:California Institute of Technology
Major Option:Biochemistry
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Hood, Leroy E.
Thesis Committee:
  • Hood, Leroy E. (chair)
  • Owen, Ray David
  • Richards, John H.
  • Attardi, Giuseppe
  • Maniatis, Thomas P.
Defense Date:3 October 1980
Funding AgencyGrant Number
NIHGM 0086
NIHGM 06965
NIHAI 10781
Record Number:CaltechTHESIS:05082018-140634895
Persistent URL:
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:10862
Deposited By: Mel Ray
Deposited On:08 May 2018 23:18
Last Modified:16 Apr 2021 22:10

Thesis Files

PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page