Figure 3. IGHV Repertoires of DEs Are Predominated by One Clonotype in T1D Subjects.

(A–C) Venn diagrams show VH gene usage by IgD⁺ (red) and IgD⁻ (yellow) DEs and B_con cells (blue) in (A) T1D#1, (B) #2, and (C) #3 patients. Graphs show percentages of the top 10 VH genes (or all 7 VH genes, in the case of T1D#2) used by IgD⁺ or IgD⁻ DEs as compared to B_con cells in each patient. Arrows point to the IGHV-04-b⁺ gene segment, which was predominantly used by IgD⁺ and IgD⁻ DEs in the three patients.

(D) Graph shows absolute number of mutations per VH gene in DEs and B_con cells in the three T1D subjects. Each dot represents an individual VH gene.

(E) Schematic shows the V_H(N1)D(N2)J_H structure with the nucleotide and amino acid sequences of the CDR3 of the x-clonotype.

(F) Venn diagram shows that the x-clonotype is one of two (red) clonotypes shared among B_con cells of the three T1D subjects.

(G) Venn diagram shows diverse VH gene usage by IgD⁺ (red) and IgD⁻ (yellow) DEs comparable to that of B_con (blue) in HC#1. Graph shows percentages of the top 10 VH genes used by IgD⁺ DEs as compared to IgD⁻ DEs and B_con cells.

(H) Comparison of CDR3 sequences of IGHV04-b⁺ clonotypes in the three T1D subjects and HC#1. Asterisk indicates gap in sequence. Note the highly conserved usage of VH04-b and JH04–01*02 by DEs in all subjects.

(I) Number of mutations per VH gene in DE cells and B_con cells. Each dot represents one VH gene.

(J) Schematic shows primers used for detection of x-clonotype in peripheral blood of genotyped T1D and HCs.

Table shows detection of x-clonotype in PBMC cDNAs of T1D and HC subjects using sequence-specific primers. Note that x-clonotype is detectable in DQ7⁺ (β57D⁺ isoform of DQ8), but not DQ8⁺ and DQ2⁺ HCs. A second probe with astringent reverse primer design produced similar results (Table S7).

See also Figure S5 and Tables S1, S4, S5, S6, and S7.