Interstitial tissues were infiltrated with large numbers of lymphocytes and plasmacytes
. Immunostaining indicated diffuse infiltration of IgG4 (+) plasma cells.
Clinical symptoms of type I allergic responses are due to a small group of plasmacytes
that secrete IgE antibodies, which bind to high-affinity FceRI receptors on basophils and mast cells, and these cells become sensitized.
FNAC of the swelling showed many epitheloid granulomas in a necroinflammatory and caseous background showing polymorphs, histiocytes and few lymph plasmacytes
. Special stain for AFB [Fig 6] showed fast staining bacilli ultimately confirming the diagnosis of tuberculous lymphadenitis (cold abscess).
A very scant stroma with inflammatory infiltration consisted of lymphocytes and plasmacytes
The polyclonal infiltrating plasmacytes
are in majority IgG4 positive.
Bronchiolar walls were moderately infiltrated by neutrophils and had multifocal epithelial necrosis and multifocal peribronchiolar moderate infiltration by macrophages and lymphocytes and few neutrophils and plasmacytes
. Bronchial lumina harbored few neutrophils and scant edema, fibrin, and cellular debris.
(94,95) This is likely because p38 MAPK inhibition leads to inhibiting IL-6 secretion induced by adherence of malignant plasmacytes
to bone marrow stromal cells, a major molecule for the survival and proliferation of myeloma cells.