Ebook High-Yield histopathology (second edition): Part 2
➤ Gửi thông báo lỗi ⚠️ Báo cáo tài liệu vi phạmNội dung chi tiết: Ebook High-Yield histopathology (second edition): Part 2
Ebook High-Yield histopathology (second edition): Part 2
General Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels drainin Ebook High-Yield histopathology (second edition): Part 2ng various anatomic regions. Histologically, a lymph node is divided into the cortex and medulla.• Figure 13-1 A: Diagram of a lymph node. Note the afferent lymphatic vessels (AL) along the convex surface; efferent lymphatic vessel (ELL artery (A), and vein (V) at the hilus; outer cortex (OC) with l Ebook High-Yield histopathology (second edition): Part 2ymphatic follicles (LF), many of which contain germinal centers; inner cortex (IC); and medulla (M) B: Diagram showing the flow of lymph and blood thrEbook High-Yield histopathology (second edition): Part 2
ough the lymph node PCV, postcapillary venule C: Light micrograph of a normal lymph node showing the subcap-sular sinus (S), outer cortex (OC), inner General Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels drainin Ebook High-Yield histopathology (second edition): Part 2 inner cortex Note the lymphocytes exiting the bloodstream to repopulate the lymph node.135136CHAPTER 13o (Inter Cortex consists of:A.MATURE (VIRGIN) B CELLS. Mature B cells are organized into lymphatic follicles that may contain germinal centers. Germinal centers arc evidence of activated B cells t Ebook High-Yield histopathology (second edition): Part 2hat begin the transformation into plasma cells.B.FOLLICULAR DENDRITIC CELLS. Follicular dendritic cells have an antigen-presenting function.c. MACROPHEbook High-Yield histopathology (second edition): Part 2
AGESD.FIBROBLASTS (RETICULAR CELLS). Fibroblasts secrete type ill collagen (reticular fibers) that form a stromal meshwork.oInner Cortex(also called tGeneral Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels drainin Ebook High-Yield histopathology (second edition): Part 2GESD. FIBROBLASTS (RETICULAR CELLS). Fibroblasts secrete type 111 collagen (reticular fibers) that form a stromal meshwork.0 Medulla consists of:A.LYMPHOCYTESB.PLASMA CELLS. Plasma cells increasingly populate the medulla of antigen-stimulated lymph nodes so that the medulla becomes a major site of i Ebook High-Yield histopathology (second edition): Part 2mmunoglobulin secretion.c. MACROPHAGES. Macrophages are very numerous in the medulla so that the medulla becomes a major site of phagocytosis.D. FIBROEbook High-Yield histopathology (second edition): Part 2
BLASTS (RETICULAR CELLS). Fibroblasts secrete type 111 collagen (reticular fibers) that form a stromal meshwork.o Flow 0Í Lymphoccurs through afferentGeneral Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels drainin Ebook High-Yield histopathology (second edition): Part 2phatic vessel with valves exiting at (he hilum. Sinuses contain sinus macrophages, veiled cells, and reticular fibers that crisscross the lumen in a haphazard fashion.o Flow of Bloodoccurs through arteries that enter at the hilum —> a capillary network within the outer and inner cortex —> postcapill Ebook High-Yield histopathology (second edition): Part 2ary' (high endothelial) venules within the inner cortex —> veins that leave at the hilum. Postcapillary (high endothelial) venules have lymphocyte homEbook High-Yield histopathology (second edition): Part 2
ing receptors and are the major site where B cells and T cells exit the bloodstream to rcpopulatc their specific portion of the lymph node. LymphocyteGeneral Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels drainin Ebook High-Yield histopathology (second edition): Part 23-2). In early fetal devei-opinent, B-cell lymphopoiesis occurs in the fetal liver. In later fetal development and throughout the rest of adult life, B-cell lymphopoiesis occurs in the bone marrow. In humans, the bone marrow is considered the primary site OÍ B-cell lymphopoiesis.A.HEMOPOIETIC STEM C Ebook High-Yield histopathology (second edition): Part 2ELLS originating in (he bone marrow differentiate into lymphoid progenitor cells, which later form B stem cells.B.B stem cells form pro-B cells, whichEbook High-Yield histopathology (second edition): Part 2
begin heavy' chain gene rearrangement.c. PRE-B CELLS continue heavy' chain gene rearrangement.D.IMMATURE B CELLS (immunoglobulin M llgM] ) begin lighGeneral Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels drainin Ebook High-Yield histopathology (second edition): Part 2IgM /lgL) ) express antigen-specific IgM and IgD on their cell surface. Mature B cells migrate to the outer cortex of lymph nodes, lymphatic follicles in the spleen, and gut-associated lymphoid tissue (GAIT) to await antigen exposure.F.EARLY IMMUNE RESPONSE1Early in the immune response, mature B cel Ebook High-Yield histopathology (second edition): Part 2ls bind antigen using IgM and IgD.2As a consequence of antigen binding, two transmembrane proteins (CD79a and CD79b) that function as signal transduceEbook High-Yield histopathology (second edition): Part 2
rs cause proliferation and differentiation of B cells into plasma cells that secrete cither IgM or IgD.General Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels draininGeneral Features (Figure 13-1). A lymph node is a small, encapsulated, ovoid to bean-shaped gland that lies in the course of lymphatic vessels draininGọi ngay
Chat zalo
Facebook