scholarly journals A Germline-Encoded Structural Arginine Trap Underlies the Anti-DNA Reactivity of a Murine V Gene Segment

2021 ◽  
Vol 22 (9) ◽  
pp. 4541
Author(s):  
Ronny Petterson dos Santos Araújo ◽  
Renato Kaylan Alves França ◽  
Napoleão Fonseca Valadares ◽  
Andrea Queiroz Maranhão ◽  
Marcelo Macedo Brigido
Keyword(s):  
B Cells ◽  
Gene Segment ◽  
Single Chain ◽  
Structural Element ◽  
Unique Region ◽  
Structural Mechanism ◽  
Surrogate Light Chain ◽  
Repertoire Selection ◽  
Hydrophilic Peptide ◽  
V Gene

Autoimmunity may have its origins of early repertoire selection in developmental B cells. Such a primary repertoire is probably shaped by selecting B cells that can efficiently perform productive signaling, stimulated by self-antigens in the bone marrow, such as DNA. In support of that idea, we previously found a V segment from VH10 family that can form antibodies that bind to DNA independent of CDR3 usage. In this paper we designed four antibody fragments in a novel single-chain pre-BCR (scpre-BCR) format containing germinal V gene segments from families known to bind DNA (VH10) or not (VH4) connected to a murine surrogate light chain (SLC), lacking the highly charged unique region (UR), by a hydrophilic peptide linker. We also tested the influence of CDR2 on DNA reactivity by shuffling the CDR2 loop. The scpre-BCRs were expressed in bacteria. VH10 bearing scpre-BCR could bind DNA, while scpre-BCR carrying the VH4 segment did not. The CDR2 loop shuffling hampered VH10 reactivity while displaying a gain-of-function in the nonbinding VH4 germline. We modeled the binding sites demonstrating the conservation of a positivity charged pocket in the VH10 CDR2 as the possible cross-reactive structural element. We presented evidence of DNA reactivity hardwired in a V gene, suggesting a structural mechanism for innate autoreactivity. Therefore, while autoreactivity to DNA can lead to autoimmunity, efficiently signaling for B cell development is likely a trade-off mechanism leading to the selection of potentially autoreactive repertoires.

scholarly journals Predominant T cell receptor V gene usage in patients with abnormal clones of B cells

Blood ◽  
1991 ◽  
Vol 77 (8) ◽  
pp. 1776-1780 ◽  
Author(s):  
CH Janson ◽  
J Grunewald ◽  
A Osterborg ◽  
H DerSimonian ◽  
MB Brenner ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
T Cell Receptor ◽  
Gene Segment ◽  
Cd8 T Cell ◽  
Cell Receptor ◽  
T Cell Subsets ◽  
Gene Usage ◽  
V Gene

We have examined alpha/beta V gene segment usage of peripheral blood CD4+ and CD8+ T cells, respectively, from patients with multiple myeloma and monoclonal gammopathy of undetermined significance, by using T cell receptor (TCR) for antigen monoclonal antibodies (MoAbs). In 7 of 16 patients we found an increase in the usage of various TCR V gene segments. The expansion was confined to either the CD4+ or the CD8+ T-cell subset, except for one patient where an abnormal pattern was observed both within the CD4+ and CD8+ T-cell subsets. In one patient 47%, and in another patient 30% of the CD8+ lymphocytes reacted with alpha V12.1 and beta V6.7 antibodies, respectively. In two other patients 29% and 40% of the CD4+ lymphocytes reacted with beta V6.7 and beta V8.1 antibodies, respectively. We conclude that T cells with a predominant V gene usage is a frequent feature in patients with abnormal clonal B cells of malignant or benign types. T- and B-cell populations are normally clonally linked in regulatory circuits. An abnormal proliferation of B cells might therefore induce, or be regulated by, an expansion of clonal T cells, as suggested by the present results.

scholarly journals Single germline VH and V kappa genes encode predominating antibody variable regions elicited in strain A mice by immunization with p-azophenylarsonate.

1987 ◽  
Vol 166 (1) ◽  
pp. 1-11 ◽  
Author(s):  
L J Wysocki ◽  
T Gridley ◽  
S Huang ◽  
A G Grandea ◽  
M L Gefter
Keyword(s):  
Immune Response ◽  
Amino Acid ◽  
B Cells ◽  
Sequence Variation ◽  
Gene Segment ◽  
Light Chains ◽  
Secondary Immune Response ◽  
Sequence Comparisons ◽  
Variable Regions ◽  
V Gene

We have cloned and sequenced the predominant germline V kappa gene segment expressed by B cells of strain A origin that synthesize antibodies with specificity for Ars. In hybridomas synthesizing anti-Ars antibodies, this V kappa gene segment (V kappa IdCR) has been found exclusively associated with the J kappa 1 gene segment without exhibiting junctional sequence variation. Sequence comparisons of the germline V kappa IdCR gene with expressed derivatives reveals that the latter frequently contain somatically introduced amino acid replacements. Taken together with results of previous structural analyses, these results show that the predominant population of IdCR+ V regions elicited in the secondary immune response is encoded by one or two combinations of V gene segments, has little junctional diversity, and is extensively diversified by somatic mutation in both heavy and light chains.

scholarly journals Predominant T cell receptor V gene usage in patients with abnormal clones of B cells

Blood ◽  
1991 ◽  
Vol 77 (8) ◽  
pp. 1776-1780 ◽  
Author(s):  
CH Janson ◽  
J Grunewald ◽  
A Osterborg ◽  
H DerSimonian ◽  
MB Brenner ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
T Cell Receptor ◽  
Gene Segment ◽  
Cd8 T Cell ◽  
Cell Receptor ◽  
T Cell Subsets ◽  
Gene Usage ◽  
V Gene

Abstract We have examined alpha/beta V gene segment usage of peripheral blood CD4+ and CD8+ T cells, respectively, from patients with multiple myeloma and monoclonal gammopathy of undetermined significance, by using T cell receptor (TCR) for antigen monoclonal antibodies (MoAbs). In 7 of 16 patients we found an increase in the usage of various TCR V gene segments. The expansion was confined to either the CD4+ or the CD8+ T-cell subset, except for one patient where an abnormal pattern was observed both within the CD4+ and CD8+ T-cell subsets. In one patient 47%, and in another patient 30% of the CD8+ lymphocytes reacted with alpha V12.1 and beta V6.7 antibodies, respectively. In two other patients 29% and 40% of the CD4+ lymphocytes reacted with beta V6.7 and beta V8.1 antibodies, respectively. We conclude that T cells with a predominant V gene usage is a frequent feature in patients with abnormal clonal B cells of malignant or benign types. T- and B-cell populations are normally clonally linked in regulatory circuits. An abnormal proliferation of B cells might therefore induce, or be regulated by, an expansion of clonal T cells, as suggested by the present results.

Distinct VDJ-H Gene Usage between Mutated and Unmutated Patients in B-CLL: Implications for Pathogenesis and Correlation with Clinical Outcome.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 970-970
Author(s):  
Katja Mauerer ◽  
David Zahrieh ◽  
Gullu Gorgun ◽  
Aihong Li ◽  
Jianbiao Zhou ◽  
...  
Keyword(s):  
B Cells ◽  
Gene Family ◽  
Somatic Hypermutation ◽  
Gene Segment ◽  
T Cell Response ◽  
Lymphocytic Leukemia ◽  
Gene Localization ◽  
Gene Usage ◽  
Vh Genes ◽  
V Gene

Abstract In B cell chronic lymphocytic leukemia (B-CLL) somatic hypermutation in the immunoglobulin variable heavy chain (IgVH) identifies two distinct prognostic variants with mutated (M) patients having better survival. Ig recombination in this disease demonstrates biased V, D and J gene usage. To determine features of VDJ recombination associated with changes in biologic behavior we sequenced and analyzed the IgH of 356 patients with B-CLL. Of 375 sequences obtained (19 patients express two VH genes), 202 (54%) were unmutated (UM) (<2% from germline) with 84 (41%) in 100% germline configuration. UM CLL overused VH1 gene family (e.g. VH1-69, VH1-2) compared to VH3 and VH4 (e.g. VH3-7, VH3-23, VH3-48, VH4-34) in M CLL (p<0.0001). Focusing on V gene segment location, D distal VH genes were overused in CLL compared to normal B cells (p=0.05). However, this was accounted for mostly by the marked over usage of a single V gene, VH1-69, used in 66 of 202 (33%) UM sequences, but 3 of 173 (2%) M cases. V gene segments usage in M CLL was similar to normal B cells (p=0.04). CLL cases overused J distal D genes (p<0.0001), mostly accounted for by overuse of DH2-2 (15%) and DH3-3 (27%) in UM cases. JH4 (37%) and JH6 (33%) were most commonly used (p<0.0001), with JH6 used more in UM cases (p<0.0001). JH5 was overused in CLL (18%) compared to healthy B cells (7%). Analysis revealed more mutations in the framework regions, but the ratio of silent to replacement mutations was elevated in the complementarity-determining regions (CDR) (3.45 vs. 1.39), consistent with antigen driven selection. Of note, this was also true in those cases with <2% mutations (5.20 vs. 1.57), normally classified within the UM group. In keeping with the notion that UM cases might also be antigen driven, we identified patients using identical CDR3 regions including 3 patients using VH3-11, DH3-10, and JH1, and 2 cases using VH5-51, DH3-3 and JH4. Among 21 cases using VH1-69, D3-3, and JH6, 4 were identical and 17 others had marked CDR3 homology. CDR3 length was significantly longer in UM than M cases (p=0.0001) with more negatively charged amino acids and lower calculated isoelectric point (median pI 3,8 vs. 4,8; p=0.005), which might reflect selection for specific structural motifs that facilitate antigen binding. We observed no statistically significant differences in predicted binding affinity of MHC Class I binding nonameric peptides in M compared to UM CLL patients (p=0.41), suggesting improved outcome in M CLL patients is not due to an increased T cell response. In keeping with the data of others, the median time from diagnosis to treatment of UM patients (22 months) was significantly shorter than of M patients (70 months) (p<0.001). Patients using D distal V genes had worse outcome (p<0.001), although this was accounted for entirely by the poor outcome of the patients using VH1-69. Time to treatment was significantly shorter for patients using the VH1 gene family (p<0.001), even when VH1-69 patients were excluded from analysis (p=0.05). We conclude that CLL is characterized by VDJ use patterns that differ distinctly between M and UM CLL patients, but with the exception of VH1-69, and potentially other VH1 family members, the location of the V gene did not influence outcome. Therefore, mechanisms other than gene localization must be responsible for the poorer outcome of CLL patients utilizing VH1-69.

scholarly journals Subnuclear cyclin D3 compartments and the coordinated regulation of proliferation and immunoglobulin variable gene repression

2012 ◽  
Vol 209 (12) ◽  
pp. 2199-2213 ◽  
Author(s):  
Sarah E. Powers ◽  
Malay Mandal ◽  
Satoshi Matsuda ◽  
Ana V. Miletic ◽  
Matthew H. Cato ◽  
...  
Keyword(s):  
Cell Cycle Progression ◽  
Gene Segment ◽  
Cyclin D3 ◽  
Cyclin D2 ◽  
Cycle Progression ◽  
Nuclear Compartment ◽  
Regulation Of Proliferation ◽  
Variable Gene ◽  
V Gene ◽  
Phosphoinositide 3 Kinase

Ubiquitously expressed D-type cyclins are required for hematopoiesis but are dispensable in other cell lineages. Furthermore, within different hematopoietic progenitor populations the D-type cyclins play nonredundant roles. The basis of this lineage and developmental specificity is unknown. In pro–B cells we demonstrate four distinct nuclear D-type cyclin compartments, including one cyclin D3 fraction associated with CDK4 and another phosphoinositide 3-kinase–regulated fraction not required for proliferation. A third fraction of cyclin D3 was associated with the nuclear matrix and repression of &gt;200 genes including the variable (V) gene segments Igkv1-117, Iglv1, and Igh-VJ558. Consistent with different subnuclear compartments and functions, distinct domains of cyclin D3 mediated proliferation and Igk V gene segment repression. None of the cyclin D3 nuclear compartments overlapped with cyclin D2, which was distributed, unbound to CDK4, throughout the nucleus. Furthermore, compartmentalization of the cyclins appeared to be lineage restricted because in fibroblasts, cyclin D2 and cyclin D3 occupied a single nuclear compartment and neither bound CDK4 efficiently. These data suggest that subnuclear compartmentalization enables cyclin D3 to drive cell cycle progression and repress V gene accessibility, thereby ensuring coordination of proliferation with immunoglobulin recombination.

The expression of Vpre-B/λ5 surrogate light chain in early bone marrow precursor B cells of normal and B cell-deficient mutant mice

Cell ◽  
1994 ◽  
Vol 77 (1) ◽  
pp. 133-143 ◽  
Author(s):  
Hajime Karasuyama ◽  
Antonius Rolink ◽  
Yoichi Shinkal ◽  
Faith Young ◽  
Frederick W. Alt ◽  
...  
Keyword(s):  
Bone Marrow ◽  
B Cells ◽  
B Cell ◽  
Light Chain ◽  
Mutant Mice ◽  
Deficient Mutant ◽  
Surrogate Light Chain ◽  
Bone Marrow Precursor ◽  
Precursor B Cells
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