scholarly journals The Structural Basis of Repertoire Shift in an Immune Response to Phosphocholine

2000 ◽  
Vol 191 (12) ◽  
pp. 2101-2112 ◽  
Author(s):  
McKay Brown ◽  
Maria A. Schumacher ◽  
Gregory D. Wiens ◽  
Richard G. Brennan ◽  
Marvin B. Rittenberg
Keyword(s):  
Immune Response ◽  
Light Chain ◽  
Indirect Effects ◽  
Somatic Mutations ◽  
Variable Region ◽  
Primary Response ◽  
Structural Basis ◽  
Antibody Repertoire ◽  
High Affinity

The immune response to phosphocholine (PC)–protein is characterized by a shift in antibody repertoire as the response progresses. This change in expressed gene combinations is accompanied by a shift in fine specificity toward the carrier, resulting in high affinity to PC–protein. The somatically mutated memory hybridoma, M3C65, possesses high affinity for PC–protein and the phenyl-hapten analogue, p-nitrophenyl phosphocholine (NPPC). Affinity measurements using related PC–phenyl analogues, including peptides of varying lengths, demonstrate that carrier determinants contribute to binding affinity and that somatic mutations alter this recognition. The crystal structure of an M3C65–NPPC complex at 2.35-Å resolution allows evaluation of the three light chain mutations that confer high-affinity binding to NPPC. Only one of the mutations involves a contact residue, whereas the other two have indirect effects on the shape of the combining site. Comparison of the M3C65 structure to that of T15, an antibody dominating the primary response, provides clear structural evidence for the role of carrier determinants in promoting repertoire shift. These two antibodies express unrelated variable region heavy and light chain genes and represent a classic example of the effect of repertoire shift on maturation of the immune response.

scholarly journals In Situ Studies of the Primary Immune Response to (4-Hydroxy-3-Nitrophenyl)Acetyl. V. Affinity Maturation Develops in Two Stages of Clonal Selection

1998 ◽  
Vol 187 (6) ◽  
pp. 885-895 ◽  
Author(s):  
Yoshimasa Takahashi ◽  
Pinaki R. Dutta ◽  
Douglas M. Cerasoli ◽  
Garnett Kelsoe
Keyword(s):  
Immune Response ◽  
Clonal Selection ◽  
Cd40 Ligand ◽  
Primary Response ◽  
Affinity Maturation ◽  
Primary Immune Response ◽  
Cellular Interactions ◽  
Serum Antibodies ◽  
High Affinity ◽  
Selection Of

To examine the role of germinal centers (GCs) in the generation and selection of high affinity antibody-forming cells (AFCs), we have analyzed the average affinity of (4-hydroxy-3-nitrophenyl)acetyl (NP)-specific AFCs and serum antibodies both during and after the GC phase of the immune response. In addition, the genetics of NP-binding AFCs were followed to monitor the generation and selection of high affinity AFCs at the clonal level. NP-binding AFCs gradually accumulate in bone marrow (BM) after immunization and BM becomes the predominant locale of specific AFCs in the late primary response. Although the average affinity of NP-specific BM AFCs rapidly increased while GCs were present (GC phase), the affinity of both BM AFCs and serum antibodies continued to increase even after GCs waned (post-GC phase). Affinity maturation in the post-GC phase was also reflected in a shift in the distribution of somatic mutations as well as in the CDR3 sequences of BM AFC antibody heavy chain genes. Disruption of GCs by injection of antibody specific for CD154 (CD40 ligand) decreased the average affinity of subsequent BM AFCs, suggesting that GCs generate the precursors of high affinity BM AFCs; inhibition of CD154-dependent cellular interactions after the GC reaction was complete had no effect on high affinity BM AFCs. Interestingly, limited affinity maturation in the BM AFC compartment still occurs during the late primary response even after treatment with anti-CD154 antibody. Thus, GCs are necessary for the generation of high affinity AFC precursors but are not the only sites for the affinity-driven clonal selection responsible for the maturation of humoral immune responses.

The human antibody repertoire: Heavy and light chain variable region gene usage in six alloantibodies specific for human HLA class I and class II alloantigens

1995 ◽  
Vol 32 (14-15) ◽  
pp. 1105-1122 ◽  
Author(s):  
Jennifer S. Andris ◽  
Sheena R. Abraham ◽  
Virginia Pascual ◽  
Maria P. Pistillo ◽  
Stefano Mantero ◽  
...  
Keyword(s):  
Light Chain ◽  
Variable Region ◽  
Hla Class I ◽  
Class Ii ◽  
Class I ◽  
Antibody Repertoire ◽  
Human Antibody ◽  
Region Gene ◽  
Variable Region Gene ◽  
Gene Usage

scholarly journals The binding of 2,4,6-trinitrophenyl derivatives to the mouse myeloma immunoglobulin A protein MOPC 315

1978 ◽  
Vol 169 (1) ◽  
pp. 179-188 ◽  
Author(s):  
Steven K. Dower ◽  
Peter Gettins ◽  
Roland Jackson ◽  
Raymond A. Dwek ◽  
David Givol
Keyword(s):  
Heavy Chain ◽  
Light Chain ◽  
Chemical Shifts ◽  
Variable Region ◽  
Proton Nuclear Magnetic Resonance ◽  
Structural Basis ◽  
Tryptophan Residue ◽  
Difference Spectra ◽  
Fab Fragment ◽  
Mouse Myeloma

The binding of Tnp (2,4,6-trinitrophenyl) derivatives to the Fv fragment (variable region of heavy and light chains) of the mouse myeloma IgA protein MOPC 315 was investigated by 270MHz proton nuclear magnetic resonance. Two of the haptens, Tnp-glycine and Tnp-l-aspartate, are in fast exchange with the Fv fragment, and the changes in chemical shifts for both protein and hapten resonances were determined by titrations. For the tightly binding hapten ε-N-Tnp-α-N-acetyl-l-lysine, which is in slow exchange with the Fv fragment, the changes in chemical shifts for the hapten H3+H5 resonances were determined by cross-saturation. By using these data and the known structure of the combining site of protein MOPC 315 [Dwek, Wain-Hobson, Dower, Gettins, Sutton, Perkins & Givol (1977), Nature (London) 266, 31–37] the mode of binding of Tnp derivatives is deduced by ring-current calculations. The trinitrophenyl ring stacks with tryptophan-93L (light chain) in the ‘aromatic box’ formed by tryptophan-93L, tyrosine-34L and phenyl-alanine-34H (heavy chain). Further evidence for the stacking interaction with a tryptophan residue is provided by the similarity of the optical-difference spectra observed with Tnp-aminomethylphosphonate in the presence of either the Fab fragment (light chain and N-terminal half of heavy chain) of protein MOPC 315 or tryptophan. These data show that the modes of binding of all the Tnp derivatives are very similar, despite a 100-fold range in their affinities. It is also concluded that the modes of binding of Dnp (2,4-dinitrophenyl) and Tnp derivatives to protein MOPC 315 are very similar, and that the structural basis for this is that the aromatic box is large enought to allow the trinitrophenyl ring to stack with tryptophan-93L while still forming hydrogen bonds to asparagine-36L and tyrosine-34L.

IG Heavy and Light Chain Variable Genes in Chronic Lymphocytic Leukemia Exhibit Distinct Somatic Mutation Patterns and a Comparable Imprint of Antigen Selection.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 1921-1921
Author(s):  
Kostas Stamatopoulos ◽  
Chrysoula Belessi ◽  
Anastasia Hadzidimitriou ◽  
Katerina Hatzi ◽  
Niki Stavroyianni ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Light Chain ◽  
Somatic Mutations ◽  
Somatic Hypermutation ◽  
Multinomial Distribution ◽  
Lymphocytic Leukemia ◽  
Distribution Model ◽  
Mutational Hotspots ◽  
Antigen Selection

Abstract We conducted a parallel analysis of somatic mutations in paired IG heavy (HC) and light chain (LC) chain genes in a series of 253 (165 κ- and 88 λ-LC expressing) chronic lymphocytic leukemia (CLL) cases. IGHV/IGKV/IGLV sequences were 100% homologous to germline in 32/33/27% of cases; had 97–99.7% homology in 50/27/37,5% of cases; less than 97% homology in 18/40/35% of cases. IGHV sequences were generally more mutated than the corresponding IGKV/IGKL sequences (average mutation load for IGHV/IGKV/IGLV genes: 94.4/96.4/96.8); 18/253 cases (7.1%) had more mutated LCs than HCs. The most frequent genes among 100% homologous sequences were IGHV4-39 and IGHV1-69 (10/16 and 9/15 cases, respectively) and IGKV1-39/1D-39 (9/19 cases); among IGLV genes, 3/13 IGLV3-21 sequences were unmutated and 9/13 had >98% homology. The most frequent genes in the “<97%-homology” subgroup were IGHV3-7 and IGHV4-34 (18/19 and 23/27 cases, respectively), IGKV3-20 (12/25 cases) and IGLV2-8 (8/14 cases). Analysis after the multinomial distribution model disclosed significant evidence for positive selection by classical T-dependent antigen from both chains in 43 cases, from HCs only in 53 cases and from LCs only in 16 cases; 27 HC+LC mutated cases (7/27 with <97% homology) had no evidence for antigen selection from either HCs or LCs. Mutations followed a similar pattern, with elevated replacement/silent (R/S) ratios in CDRs (mean, 2.8, 2.6 and 3.7 for IGHV, IGKV and IGLV, respectively) and decreased R/S in FRs (mean, 1.4, 1.5 and 1.6 for IGHV, IGKV and IGLV, respectively). R mutations in FRs usually led to substitution by aminoacids of similar charge and size. The somatic hypermutation process generally spread diversity to the periphery of the CDR1 region. Mutational “hotspots” differed not only between HCs and LCs but among subgroups (eg, IGHV1 vs. IGHV3 vs. IGHV4: thus, S-92 in IMGT-FR3 was mutated in 52/21/5% of IGHV4/3/1 sequences; IGKV1/3 vs. IGKV2 subgroup genes; IGLV1 vs. IGLV3 subgroup genes) or even individual genes, e.g. IGHV1-8, IGHV3-23, IGHV4-34, IGKV2-30, IGLV3-21; in this context, a subgroup of three mutated IGHV4-34 sequences was identified, all in sIgG+ cases, with similar HCDR3 regions and associated with IGKV2-30 κ-LCs with identical KCDR3; furthermore, in the case of IGLV3-21, an already described association with IGHV3-21 HCs was again noted in our series (three cases). Importantly, some IMGT positions were universal “hotspots” (eg. 32 in IMGT-CDR1) or “coldspots” (both invariant C at IMGT positions 23/104 in all sequences; IMGT positions 41, 43, 74, 75 and 102 for all IGHV subgroups; 16, 41, 76, 87, 89 and 98 for all IGKV subgroups; 41, 43, 50, 70, 76, 83, 89, 98, 99 and 102 for all IGLV subgroups). Finally, IGLV sequences showed a lower incidence of CDR1 and FR2/3 mutations compared to IGKV sequences. In conclusion, a complementary imprint of antigen selection in CLL might be witnessed either by IGHV, IGKV or IGLV rearranged sequences. These results provide further evidence for the role of antigen selection in the pathogenesis of at least a proportion of CLL cases.

scholarly journals Role of light chain variable region in myeloma with light chain deposition disease: evidence from an experimental model

Blood ◽  
1995 ◽  
Vol 86 (10) ◽  
pp. 3655-3659 ◽  
Author(s):  
AA Khamlichi ◽  
A Rocca ◽  
G Touchard ◽  
P Aucouturier ◽  
JL Preud'homme ◽  
...  
Keyword(s):  
Experimental Model ◽  
Light Chain ◽  
Variable Region ◽  
Light Chain Deposition Disease ◽  
Deposition Disease ◽  
Kappa Chain ◽  
V Region ◽  
Light Chain Deposition

Light chain deposition disease (LCDD) results from a propensity of some human monoclonal L chains to form tissue deposits. We designed an experimental model for in vivo expression of human kappa L chain sequences in mice and compared a somatically mutated LCDD chain with a closely related control kappa chain, both encoded by the unique V kappa IV gene. Mice secreting the LCDD chain but not those producing the control chain showed deposits with a distribution similar to that observed in patients. These data show that discrete changes in V region sequences can play a major role in tissue deposition of human L chains.

scholarly journals Inhibition of calmodulin-dependent myosin light-chain kinase by growth-hormone-releasing factor and vasoactive intestinal peptide

1994 ◽  
Vol 300 (3) ◽  
pp. 901-905 ◽  
Author(s):  
H Shiraga ◽  
D Stallwood ◽  
M Ebadi ◽  
R Pfeiffer ◽  
D Landers ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Enzyme Activity ◽  
Vasoactive Intestinal Peptide ◽  
Light Chain ◽  
Myosin Light Chain Kinase ◽  
Functional Role ◽  
Myosin Light Chain ◽  
Growth Hormone Releasing Factor ◽  
High Affinity

In view of the ability of calmodulin to bind vasoactive intestinal peptide (VIP) and growth-hormone-releasing factor (GRF) with high affinity [Stallwood, Brugger, Baggenstoss, Stemmer, Shiraga, Landers and Paul (1992) J. Biol. Chem. 267, 19617-19621], the effects of these neuropeptides on a model calmodulin-dependent enzyme, myosin light-chain kinase (MLCK), were studied. Both peptides were potent inhibitors of MLCK activity. The inhibition of enzyme activity by VIP and GRF was progressively overcome with increasing calmodulin concentrations, with no inhibition observed at a saturating calmodulin concentration. Nanomolar concentrations of MLCK blocked the formation of calmodulin-[125I-Tyr10]VIP complexes. These data provide support for a functional role of VIP and GRF binding by calmodulin.

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