PMC6821675_01
Axillary lymph node biopsy from an HIgM A-T patient. (A) Lymph node biopsy with paracortical expansion (A, 20X) consisting of a mixture of small lymphocytes, plasma cells, and immunoblasts (B, 200X). Immunohistochemical staining for IgD (C) and IgM (D) demonstrate cytoplasmic staining of plasma cells and lymphocytes.
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F1
Tfh cells, and abundant polytypic, plasmablasts (Figures 1A,B). There were no granulomas, and EBV was not detected. IgM and IgD were detected diffusely (Figures 1C,D), IgG staining was sparse, and IgA staining was absent.
Baseline B cell abnormalities worsened following TNF blockade. Two-dimensional flow cytometry plot of the patient's CD20+ B cells 1 year before (A) and 1 year after (B) initiating adalimumab therapy. The patient's plots are on top and underneath each plot is the same day normal control sample.
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F2
Serum IgM level at the time of biopsy had increased to 4,000 mg/dl, and her blood CD20+ B cells experienced a global decrease in surface IgD expression (Figures 2A,B).
Renal biopsy at age 6 years. Necrotic and inflamed arteries (black arrows; A:hematoxylin eosin stain; B:trichrome stain). IgG (C), IgM (D), C3 (E), C1q (F), and fibrinogen (G) deposition seen in a small necrotic artery by immunofluorescent staining. (H) Electron micrograph demonstrating subendothelial widening along a glomerular capillary loop (black arrows).
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F3
Histologic staining of the kidney demonstrated acute and chronic necrotic, inflamed arteries with thrombosis and various amounts of intimal thickening (Figures 3A,B,G,H), and strong IgG, IgM, C3, and C1q staining (Figures 3C-F).