Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0029713 (immaturity)
 4,335 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To study the morphologic alterations of pulmonary elastic fibers in cynomolgus monkeys with paraquat toxicity, peroxidase- and ferritin-labeled antielastin antibodies were used for the light and electron microscopic localization of elastin. One week after paraquat, alveolitis, tissue damage and alveolar dilatation were present; elastic fibers were frayed and more diffusely and intensely stained than those of control animals. In the latter, staining was localized in peripheral regions of the amorphous components and, to a lesser extent, in some microfibrils of elastic fibers. At 3 to 4 weeks, diffuse staining was evident in damaged interstitial elastic fibers and in newly formed elastic fibers in areas of intraalveolar fibrosis. At 8 weeks, the interstitium contained many elastic fibers which showed staining only in peripheral regions of the amorphous components. These observations suggest that: 1) preembedding immunohistochemical staining for elastin is localized in peripheral regions of normal elastic fibers because the antielastin antibody can penetrate into mature and undamaged amorphous components only to a very limited extent; 2) in early stages of paraquat toxicity this staining is more diffuse and intense because elastase from inflammatory cells partially degrades the elastic fibers and permits greater penetration of the antibody into the amorphous materials; 3) in later stages the staining pattern returns to normal as inflammation subsides and elastic fibers are repaired; however, newly formed elastic fibers in areas of intraalveolar fibrosis stain diffusely, reflecting increased penetration of the antibody because of immaturity and incomplete cross-linking, and 4) degeneration of elastic fibers of alveolar walls in paraquat lung may lead to alveolar dilatation, which is associated with irregular fibrosis and constitutes one of the processes of pulmonary structural remodeling in paraquat lung.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Pulmonary elastic fiber degradation in paraquat toxicity. An electron microscopic immunohistochemical study. 337 Jun 14

We have previously shown that degranulated guinea pig basophils in vitro do not die. Rather, they recover, and these mature cells rebuild granules in the absence of nuclear changes of immaturity or of mitoses. This ability to survive the explosive release of cytoplasmic granules and to rebuild granules was the first such demonstration for a mature granulocyte. We utilized this model of antigen-induced basophil degranulation and recovery in vitro, in conjunction with a specific antibasophil serum (ABS) and indirect immunoferritin electron microscopy, in order to localize the anatomic sites of expression of the antigen(s) recognizing ABS during the secretory and recovery events. Basophil surface membranes were labeled prior to degranulation, during degranulation, after degranulation, and as mature, polynuclear, granule-free cells began to rebuild new granules. In addition, the plasma membranes of non-granule-containing, glycogen positive, small mononuclear cells were labeled. These were few in number and were thought to be precursor cells in the basophil lineage. Controls, either nondegranulated basophils at a variety of culture intervals, or basophils following degranulation and during recovery, were done using normal rabbit serum (NRS) and an indirect immunoferritin electron microscopic technique. These were all negative. Moreover, contaminating eosinophils, neutrophils, and lymphocytes were also negative. Extruded granules were labeled with ferritin (ABS) on their membrane-free, finely granular exteriors, but not within the lamellar array of their matrixes. Extruded granules were not labeled in control experiments. When tested with ABS, membrane-bound granules in the cytoplasm prior to release and membrane-free, released granules contained within degranulation sacs, were negative, as was the membrane of sacs. Immature, membrane-bound granules were also negative. Ferritin binding to membranes was seen in narrow channels, vesicles, and larger vacuoles, as well as in multivesicular bodies, present in the peripheral cytoplasm. This distribution of labeled sites was not observed in neutrophils, eosinophils, and lymphocytes which were also routinely present in these preparations. These sites were not labeled in basophils or other cells in control studies using ferritin and NRS. This indicates the necessity for specific binding to basophils in order to visualize this process. Whether most such sites represent residual endocytosis at 4 degrees C or binding to open invaginations near surfaces of cells does not detract from their specificity and thus expression of specific antigen(s)-binding sites in basophils.
 ...
PMID:Immunoferritin electron microscopic studies with antibasophil serum of guinea pig basophil degranulation and regranulation in vitro. 402 21