ABSTRACT
<p><b>OBJECTIVE</b>The aim of this study was to investigate the ability of Pref-1+ adipocyte progenitor cells to mobilize into mesenteric lymph nodes (MLNs) and the dynamic expression of related chemokines during the development of rat MLNs.</p><p><b>METHODS</b>Immunohistochemical analyses were used to detect the expression of Pref-1 and related chemokines. Transmission electron microscopy (TEM) was used to observe the changes in ultrastructure of MLNs.</p><p><b>RESULTS</b>Cells containing lipid droplets were found in all rat MLNs at embryonic day (E) 18.5, 2 and 6 weeks (w) after birth, and they were similar to fibroblastic reticular cells (FRCs) or follicular dendritic cells (FDCs) under TEM. Pref-1+ adipocyte progenitor cells were found in all MLNs. The expression level of Pref-1 was significantly increased at 2 w after birth and decreased at 6 w after birth. The tendency of Cxcl12 expression was consistent with that of Pref-1 and was positively correlated with the expression of Pref-1 (P < 0.01; r = 0.897). At E18.5, Cxcl13, and Ccr7 were significantly expressed in the MLN anlage, but the expression level of Ccl21 was low. The expression level of Cxcl13, Ccr7, and Ccl21 in MLN were significantly increased at 2 w after birth (P < 0.05), while the expression of Ccr7 and Ccl21 were significantly decreased at 6 w after birth (P < 0.05).</p><p><b>CONCLUSION</b>Adipocyte progenitor cells are involved in the rat MLNs development through differentiation into FRC and FDC. The expression of the relevant chemokines during the development of MLNs is dynamic and may be related to the maintenance of lymph nodes self-balance state.</p>
Subject(s)
Animals , Female , Pregnancy , Rats , Chemokines , Genetics , Metabolism , Gene Expression Regulation, Developmental , Physiology , Intercellular Signaling Peptides and Proteins , Genetics , Metabolism , Lymph Nodes , Embryology , Metabolism , Membrane Proteins , Genetics , Metabolism , Mesentery , EmbryologyABSTRACT
<p><b>OBJECTIVE</b>To investigate the relationship between the extracellular matrix (ECM) and neoplastic progression in hamster with tongue cancer.</p><p><b>METHODS</b>Forty-eight specimens of hamster tongue cancer were divided into control group (n=6) and experimental group (n=42). The pathological grade of the specimens was assessed (including 3 stages, namely atypical hyperplasia, carcinoma in situ and early invasive carcinoma). The sections of the tongue were stained with Masson and aldehyde-fuchsin (AF) staining for microscopic observation of the elastic fiber and collagen fiber changes.</p><p><b>RESULTS</b>Within the connective tissue cores (CTC) of the papillae in the control group was a framework of numerous and fine Gomrori's aldehyde fuchsin-positive elastic fibers. But in the stages of dysplasia and carcinoma in situ, these elastic fibers decreased and further diminished in the CTC in early invasive carcinoma. In dysplasia and carcinoma in situ stages, most of the elastic fibers collapsed with scattered elastic fibers, and the elastic fibers decreased significantly in early invasive carcinoma. The control group showed a significantly greater number of elastic fibers in the experimental group. The collagen fiber was obviously increased and irregularly arranged in dysplasia and carcinoma in situ stage; in early invasive carcinoma, the collagen fibers became thicker with deposition in the lamina propria.</p><p><b>CONCLUSION</b>An excessive deposition of collagen fiber and reduction of the elastic fibers is an important factor contributing to the development of tongue carcinoma in hamsters.</p>