Immunohistochemical localization of proteoglycans in interstitial elements of human pancreas and biliary system

Summary The immunohistochemical localization of large proteoglycan and small proteoglycan was observed, using antibodies 2B1 and 6B6 (Sobueet al., 1988, 1989a), in fetal and adult pancreas and biliary system as well as in tumour tissues, obtained from 11 autopsies and 74 biopsies. The distribution of chondroitin 4- and 6-sulphate side chains, type I and IV collagen and elastin were also studied. In adult pancreas and all the biliary tracts examined, periductal fibrous tissues consisted mainly of dermatan sulphate small proteoglycan with networks of fibrous elements, which were composed of large proteoglycan, elastin, type I collagen and type IV collagen. In the interstitial components of cystadenoma of pancreas and biliary duct carcinoma, similar small proteoglycan-rich components were relatively abundant, although large proteoglycan was present in much larger amounts than that in non-neoplastic adult tissues. In some cholangiomas, the extra-and intracellular hyaline globules formed by the carcinoma cells were found to contain chondroitin sulphate large proteoglycan, laminin and fibronectin.The distribution of proteoglycans was observed to be different in the arterial walls of the interlobular tissues of the adult and the fetal pancreas. The biological significance of large and small proteoglycans in the interstitial connective tissues was discussed.     

High cell density perfusion culture of hybridoma cells recycling high molecular weight components

We have developed a high cell density and high product concentration culture system recycling high molecular weight components. The production of monoclonal antibodies in high concentration was performed by this culture system with mouse human hybridoma H2 and V6 cells in serum-free defined media.The concentration of IgG after 48 days culture of H2 cells in ITES-eRDF reached 2 mg/ml and the purity of IgG in culture fluid was 61%. In addition, high molecular weight components in serum-free media, such as transferrin or BSA, could be reduced to 5% of the original concentration.     

In vivo Studies on the Occurrence of Stored mRNA in Embryonic Axes of Vigna unguiculata Seeds

-Amanitin and cordycepin at various concentrations were testedfor their inhibitory effect on the fresh weight increase ofVigna unguiculata embryonic axes after the onset of imbibitionand on the incorporation rate of ³H-labeled leucine into proteinin axes of the 36–38 h stage. -Amanitin at 0.5–5µ/Kg/ml clearly exerted an inhibitory effect on both thefresh weight increase and the protein synthesis. This drug at1 µg/ml, however, showed no significant effect on theprotein synthesis at an early stage of imbibition (4 h), whereascycloheximide was a very potent inhibitor. By experiments inwhich ‘dry’ axes were allowed to imbibe 3H-lebeledadenosine solution for 4 and 12 h in the presence of -amanitin,it was found that poly A⁺RNA was newly synthesized to some extentin axes as early as 4 h after the onset of imbibition and thatthe drug effectively inhibited the poly A⁺RNA synthesis. Theresults may indicate the occurrence of stored mRNA in embryonicaxes of V. unguiculata seeds. (Received June 11, 1983; Accepted August 16, 1983)     

Electron microscopical studies on the thyroid of a cyclostome,Lampetra japonica,during its upstream migration

Summary Electron microscopical studies were made of the thyroid gland of an adult lamprey, Lampetra japonica, in the upstream migration period.The thyroid consists of many usual follicles containing the colloid in their lumina, and a large parafollicle without colloid. The paper concerns only the usual follicle.The follicle cells found in the usual follicle wall are classified into three types; 1. a non-ciliated taller cell, 2. a ciliated taller one, and 3. a non-ciliated cuboidal one. From their cytoplasmic fine structure, it is considered that all these cells are essentially identical and differences among them are due to their functional state.All these type cells are characterized by irregularly developed interdigitations and aggregates of tonofilaments throughout the cytoplasm, especially in the perinuclear region. Although the rough-surfaced endoplasmic reticulum and the Golgi apparatus are fairly well developed in the first and second type cells, the cisternae are not so large-vacuolated but flattened, and the cytoplasm is more compact as compared with that of the higher vertebrate. In the third type cell, the cytomembranes are poorly developed.Large dense inclusion-bodies consisting of heterogeneously dense materials, of lamellar structures, and of less dense vacuoles, which are found often in taller follicle cells, are also characteristic for the lamprey thyroid. The body which might be intimately related to the Golgi apparatus is considered to be a kind of lysosomes and it perhaps corresponds to the yellow pigment observed by light microscopy.In the apical part of the cytoplasm in taller cells, there are three kinds of granules or vesicles; numerous small vesicles considered to be derived from the Golgi apparatus, a few small dense granules which seem to originate from the Golgi region, and a few large less-dense granules.In the third type cell, the cytomembranes are not so well developed as those of the first and second type cells. The large heterogeneously dense bodies and the cytoplasmic granules are very few in number.Around the follicle of the lamprey thyroid, there are a dense basement membrane and a relatively compact connective tissue with few blood capillaries. Characteristic fat cells are found in the connective tissue.     

Immunohistochemical demonstration of urotensins I and II in the caudal neurosecretory system of the Japanese charr,Salvelinus leucomaenis,retained in sea water

This paper is concerned with part of the role and function of the caudal neurosecretory system of the charr,Salvelinus leucomaenis, studied by immunohistochemistry. In order to elucidate the different histologic changes, we examined the immunoreactivities of urotenisn I (UI) and urotensin II (UII) in 3 experimental groups: the feral (river) fish, the fresh-water aquarium-, and sea water aquarium-retained fish. Coexistence of UI and UII was demonstrated in most of the smaller and larger neurons distributed in and near the urophyseal system of all 3 groups. However, some of the larger neurons were immunoreactive only to a single hormone, UI or UII. Merely a few neurons indicated no reactivity for either UI or UII. No such clearcut differences were encountered immunohistochemically in the 3 groups. Neuronal and urophysial immuno-reactivity to UI of feral and fresh-water-retained fish was slightly stronger than that of sea water-retained fish. Moreover, in sea water-retained fish, the intensity of immunoreactivity for UI was variable, and the number of neurons positive for UII only was somewhat larger than that in feral and fresh-water-retained fish. A series of UII-positive cerebrospinal fluid (CSF)-contacting neurons were seen in the ependymal and subependymal layers ventral to the central canal of the spinal cord in every group. These CSF-contacting neurons might constitute another neurosecretory system aside from the ordinary caudal neurosecretory system equipped with urophysis. In contrast to the hypothalamohypophysial neurosecretory system, the caudal neurosecretory system did not show any significant changes among the 3 groups. This suggests that urotensins I and II have no essential role in osmoregulation of the charr.     

Microheterogeneity of PSI-E Subunit of Photosystem I in Nicotiana sylvestris

Microheterogeneity of a photosystem I (PSI) subunit encodedby a nuclear gene psaE was examined in Nicotiana sylvestris,with the aid of cDNA cloning, peptide mapping analysis and proteinsequencing. The psaE product of this plant has four isoformswhose mobilities in PAGE are slightly different from each other.We isolated two types of psaE cDNAs from a N. sylvestris cDNAlibrary, and designated the corresponding genes as psaEa andpsaEb, respectively. The psaEa and psaEb genes are 77% homologousat DNA level, and their translation products share 80.4% homologyfor the precursor proteins and 89.1% for the mature forms. Comparativeanalysis of the four isoproteins and the putative products ofthe two psaE genes revealed that two isoproteins out of fourare derived from psaEa gene, and the difference between thesetwo isoproteins lies in the respective presence or absence ofN-terminal alanine. Likewise, the other two proteins are derivedfrom psaEb with similar N-terminal heterogeneity. These resultsindicate that multi-gene organization and heterogeneous N-terminalformation at post-translational level are two possible causesfor PSI subunit polymorphism in isogenic plant lines. (Received October 8, 1993; Accepted November 30, 1993)