Journal: Life science alliance
Article Title: Oral bacteria induce IgA autoantibodies against a mesangial protein in IgA nephropathy model mice.
doi: 10.26508/lsa.202402588
Figure Lengend Snippet: Figure 5. The gddY auto-Abs reacted with commensal bacteria in the oral cavity of the gddY mice. (A, B) WB analysis of lysates of bacteria from feces (fecal), small intestine (SI), and oral cavity (oral) of gddY mice blotted with sera from gddY mice (A) or culture supernatant of leukocytes from gddY mouse kidneys (B) as the primary Abs and anti-IgA as the secondary Ab. The IgA concentration in the primary Abs was adjusted to 1 μg/ml by dilution. The bacteria were cultured anaerobically on brain heart infusion agar before lysis. (C, D, E, F) FCM analyses of cultured bacteria stained with various Ab solutions (containing 1 μg/ml IgA) and SYBR Green (for bacterial DNA). (C, D) Bacteria from the oral cavity (oral) or small intestine (C), or oral bacteria from BALB/c or gddY mice (D), were stained with sera from gddY mice. (E) Oral bacteria from gddY mice were stained with the culture supernatant of leukocytes from the indicated organs of gddY mice. (C, D, E) APC-conjugated anti-mouse IgA was used as secondary Ab. The secondary Ab alone did not stain cultured bacteria (data not shown). (F) Oral or fecal bacteria from gddY mice cultured under the indicated conditions were stained with rmAb#66 or rmAb#NP, followed by Alexa Fluor 647–anti-human IgG. (C, D, E) The frequencies of IgA-bound bacteria among whole bacteria stained with SYBR Green are plotted. Data are presented as means ± SD of biological replicates. (G) rmAb#66 (1 μg/ml) was incubated with the indicated concentrations of recombinant CBX3 or OVA in equal volumes for 20 min at RT, mixed with cultured oral bacteria from gddY mice, and incubated overnight on ice. The bacteria were stained with Alexa Fluor 647-anti-human IgG to detect bound rmAb#66, together with SYBR Green to label the bacteria, and analyzed by FCM. The frequencies of rmAb#66-bound bacteria among all bacteria were plotted. Data are presented as means ± SD of three technical replicates. *P < 0.05; ***P < 0.005; ****P < 0.001. P-values were calculated using unpaired t test. One of two independent experiments with similar results is shown in each panel. Source data are available for this figure.
Article Snippet: For FCM, the following Abs were used: anti-mouse IgA-APC (clone 11- 44-2; Southern Biotech), anti-mouse CD73-biotin (clone TY/11.8; BioLegend), anti-mouse CD45-PerCP-Cy5.5 (clone 30-F11; BioLegend), anti-mouse CD31-PE (clone 390; BioLegend), anti-mouse TER119BV510 (clone TER-119; BioLegend), rabbit polyclonal anti-HP1γ (CBX3) Ab (2619; Cell Signaling Technology), rabbit monoclonal anti-HP1β (CBX1) Ab (8676; Cell Signaling Technology), rabbit IgG (for isotypematched control; 011-000-003; Jackson ImmunoResearch), antirabbit IgG-BV421 (clone Poly4064; BioLegend), and anti-human IgG Fcγ-Alexa Fluor 647 (709-606-098; Jackson ImmunoResearch).
Techniques: Bacteria, Concentration Assay, Cell Culture, Lysis, Staining, SYBR Green Assay, Incubation, Recombinant