The cells labeled with the arrows in the figure synthesize which of the following?

The cells labeled with the arrows in the figure synthesize which of the following ?

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ANS:IgE

The cells delineated by the arrows in the photomicrograph are plasma cells that are responsible for immunoglobulin (antibody) production. Plasma cells produce all the immunoglobulins: IgG, IgA, IgM, IgD, and IgE and are derived from B lymphocytes. The differentiation of plasma cells requires macrophages (antigen-presenting cells),which phagocytose and present antigen + MHC II and T-helper cells. Plasma cells are characterized by eccentric nuclei with coarse granules of heterochromatin arranged in a radial pattern about the nuclear envelope. Membrane-bound ribosomes are extremely plentiful, providing the cytoplasm with a characteristic intense basophilia. The ribosomes are involved in antibody production, principally immunoglobulin G (IgG). The juxtanuclear region, which does not stain, represents the Golgi complex, in which the antibodies are processed for secretion. The function and origin of the connective tissue cells is summarized in the table below.

Cell Type Origin Function
Fibroblast Mesenchyme Synthesis of fiber (collagen, elastic, reticular)
and ground substance (proteoglycans and
glycoproteins of connective tissue matrix
Macrophages (e.g.,
Kupffer cells,
Langerhans cells and
microglia) Monocyte (bone
marrow) Phagocytosis, antigen presentation, produce
and respond to cytokines.
Lymphocytes T
lymphocytes Bone marrow
(thymuseducated) Cell-mediated immunity (CD8+) and helper T cells (CD4+)
B lymphocytes Bone marrow
(bone marroweducated) Humoral immunity
Plasma cell B lymphocyte Immunoglobulin secretion
Neutrophils (PMNs) Bone marrow First cells to enter an inflammation site, secrete
myeloperoidase, phagocytose bacteria, and die
(forming pus)
Eosinophils Bone marrow Source of major basic protein, histaminase
(breakdown of histamine), arylsulfatases
(degradation of leukotrienes), phagocytosis of
antigen-antibody complexes and parasites
Basophils Bone marrow
(different stem
cell from mast
cell) Blood source of histamine
Mast cells connective
tissue mast cells
(CTMC) and mucosal
mast cells (MMC) Bone marrow CTMC are T-lymphocyte independent, MMC
are T-lymphocyte dependent, secrete histamine
and slow-reacting substance of anaphylaxis
[(SRS-A) increase vascular permeability],
heparin (anticoagulant), eosinophil
chemoattractant factor of anaphylaxis [(ECFA),
chemoattraction of eosinophils],
leukotrienes (smooth muscle contraction)