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The introduction of pathogens and foreign proteins into the human body can stimulate immune recognition, leading to inflammatory and allergic responses. Aspects of these responses are subject to pharmacological modulation. Before describing the actions of pharmacological agents affecting allergy and immunity, this chapter describes the cellular and molecular basis of immune and allergic responses and the points of pharmacological intervention. Subsequent chapters in this section cover in detail the classes of agents that can alter allergic and immune responses, as well as the biology and pharmacology of inflammation.
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Abbreviations
Ag: antigen
APC: antigen presenting cell
BCR: B-cell receptor
C#: complement component # (e.g. C3, C5)
CD: cluster of differentiation
CLL: chronic lymphocytic leukemia
CR#: complement receptor #
CTL: cytotoxic T lymphocyte
CTLA-4: cytotoxic T-lymphocyte–associated protein 4
DC: dendritic cell
HLA: human leukocyte antigen
HSC: hematopoietic stem cell
IFN: interferon
Ig: immunoglobulin
IL: interleukin
iNOS: inducible nitric oxide synthase: NOS2
IRF#: interferon regulatory factor #
ISG: interferon-stimulated gene
ISRE: interferon-stimulated response element
LTB4: Leukotriene B4
MADCAM-1: mucosal vascular addressin cell adhesion molecule 1
MALT: mucosa-associated lymphoid tissue
MHC: major histocompatibility complex
NK cell: natural killer cell
NO: nitric oxide
NSAID: nonsteroidal anti-inflammatory drug
PAMP: pathogen-associated molecular pattern
PD1: programmed cell death protein 1
PRR: pattern recognition receptor
Rh: rhesus
ROS: reactive oxygen species
ST: short term
TAP: transporter associated with antigen processing
TC: cytotoxic T cell
TCR: T-cell receptor
TFH: follicular helper T cells
TH: helper T cell
TLR: toll-like receptor
TNF-α: tumor necrosis factor alpha
TReg: T-regulatory cells
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CELLS AND ORGANS OF THE IMMUNE SYSTEM
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All blood cells, including immune cells, originate from pluripotent hematapoietic stem cells (HSCs) of the bone marrow. HSCs are a population of undifferentiated progenitor cells that are capable of self-renewal. On exposure to cytokines and contact with the surrounding stromal cells, HSCs can differentiate into megakaryocytes (the source of platelets), erythrocytes (red blood cells), and leukocytes (white blood cells). This process is known as hematopoiesis (Figure 34–1).
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The HSC pool can be divided in two populations: long-term (LT) and short-term (ST) HSCs. LT-HSCs are capable of lifelong self-renewal, allowing for continuous hematopoiesis throughout life. ST-HSCs have limited self-renewing capability, and differentiate into multipotent progenitors—the common myeloid progenitor (CMP) and the common lymphoid progenitor (CLP). The CMP gives rise to the myeloid lineage of cells that includes megakaryocytes; erythrocytes; granulocytes (neutrophils, eosinophils, basophils, mast cells); monocytes; macrophages; and dendritic cells (DCs).. In contrast, the CLP gives rise to the lymphoid lineage of cells that includes natural ...