Direct isolation of mycoplasmas and acholeplasmas from sera and kidneys of calves.

Kidneys and sera of calves from various farms and primary kidney tissue cultures were tested for mycoplasma and acholeplasma contamination. Altogether 24 strains belonging to Mycoplasma arginini and Acholeplasma axanthum were isolated from tissue cultures, kidneys and sera. The same species were detected from lungs and peribronchial lymph nodes of calves, together with A. laidlawii, A. modicum and M. bovirhinis species. There was a close correlation between the mycoplasma content of tissue cultures, sera and kidneys and the clinical picture observed in the farm, as well as between the quality of tissue cultures and the mycoplasma content of organs, sera and tissue cultures.     

Scopolin, a Biochemical Marker for Resistance to Thielaviopsis basicola in Callus and Crown-Gall Tissue Cultures of Tobacco

Scopolin concentration increased in tissue cultures where Thielaviopsis basicola growth ceased (primary and established callus cultures of the resistant tobacco cultivar Ky 170) while it decreased in tissue cultures where fungal growth persisted (primary and established callus cultures of the susceptible tobacco cultivar Ky 151 and crown-gall cultures of Ky 170 and Ky 151). The concentration of chlorogenic acid, scopoletin, and two other unknown soluble phenols varied after inoculation and no, correlation with tissue culture resistance could be established. Incorporation of Agrobacterium tumefaciens T-DNA in the genome of both cultivars induced a drastic reduction of scopolin in inoculated tissue cultures. T-DNA incorporation had less, influence on uninoculated tissues. Scopolin at concentrations found in tissue cultures was not toxic to the fungus.     

Effect of lunar materials on plant tissue culture

Lunar material collected during the Apollo 11, 12, 14, and 15 missions has been used to treat 12 species of higher plant tissue cultures. Biochemical and morphological studies have been conducted on several of these species. Tobacco tissue cultures treated with 0.22 g of lunar material exhibited increased greening more complex chloroplasts, less cytoplasmic vacuolation and greater vesiculation. Pine tissue cultures reacted to treatment by an increased deposition of tannin-like materials. The percentage of dry weight and soluble protein was increased in cultures treated with either lunar or terrestrial rock materials. Lunar Science Institute Contribution.     

Two-Hour Embedding Procedure for Intracellular Detection of Viruses by Electron Microscopy

An embedding method requiring only 2 h to complete and giving excellent ultrastructural preservation has been used for the rapid detection of viruses in tissue cultures. The method has also been applied successfully to mammalian tissue. It provides a rapid technique for identifying viruses isolated in tissue cultures, for screening cultures for adventitious agents, and for examining tissue biopsies for viruses.     

Intense association of non-culturable endophytic bacteria with antibiotic-cleansed in vitro watermelon and their activation in degenerating cultures

The study was undertaken with a view to unravel the source of bacterial colony growth observed in a section of micropropagated triploid watermelon cultures that were supposedly cleansed of the associated endophytic bacteria through antibiotic treatment, and thereafter maintained under stringent sterility checks to prevent lateral intrusion of contaminants. Five different bacteria were retrieved from colony growth-displaying watermelon cultures that were previously treated with gentamycin and five isolates from cefazolin-treated stocks with the organisms showing tolerance to the respective antibiotic. These watermelon cultures were in degeneration phase (over 6 months after the previous sub-culturing), while the actively maintained counterpart stocks appeared healthy with no colony growth on different bacteriological media during tissue-screenings. The latter cultures, however, revealed abundant motile, tetrazolium-stained bacterial cells in microscopy, suggesting tissue colonization by non-culturable endophytes. PCR screening on healthy cultures endorsed tissue colonization by different bacterial phylogenic groups. A few organisms could be activated to cultivation from healthy watermelon stocks through host tissue extract supplementation, which also enhanced the growth of all the organisms. The study indicated that a fraction of antibiotic-tolerant bacteria survived intra-tissue in non-culturable form during the preceding cleansing activity, multiplied to substantial numbers thereafter, and turned cultivable in degenerating cultures contributed by tissue breakdown products. This study brings out the existence of a deep endophyte association in tissue cultures which is not easily dissociable. It also signifies the utility of in vitro system for investigations into plant–endophyte association and to bring normally non-culturable novel organisms to cultivation facilitating their future exploitation.     

Interaction of Staphylococcal Alpha Toxin and the Estrogenic Hormone Diethylstilbestrol

Previous work in this laboratory showed that diethylstilbestrol was capable of suppressing induced furunculosis in rabbits. The present study indicates that the synthetic estrogenic hormone diethylstilbestrol which is used for acne, estrogen deficiency, cancer, and other disorders, can reduce the cytolytic action of staphylococcal alpha toxin. The cytotoxic action of purified alpha toxin for tissue cultures was evaluated by use of such parameters as total and viable cell counts, glucose, and protein determination, and cytopathic effects (CPE) in the presence and absence of steroids. To 3-day-old primary rabbit baby kidney tissue cultures, 1 to 5 μg of diethylstilbestrol per ml was added; growth of tissue cultures in Eagles medium was continued till the 6th day, and then one tissue cytopathic dose per milliliter of alpha toxin was added, and the subsequent fate of tissue cultures was assayed. Such cultures yielded higher total and viable cell counts, utilized more glucose, and contained more protein than the control cultures. In control cultures, CPE was observed on the 3rd hr after the addition of alpha toxin, and it was complete in 24 hr, whereas in tissue cultures treated with diethylstilbestrol, the CPE was significantly reduced. The data presented in this study made possible the availability of a suppressor of the cytolytic action of alpha toxin and might be useful in assaying the action of alpha toxin in an in vitro inexpensive test system.     

Comparative Sensitivity of Tissue Cultures to Rubella Virus: Use of Guinea Pig Cells for Virus Titration

A series of 19 different primary and serial tissue cultures were investigated for their sensitivity to virulent or attenuated rubella virus (RV). Primary guinea pig tissues, a serial passage of baby hamster kidney, and primary human amnion were comparable to African green monkey kidney tissue cultures in their sensitivity. In general, primary human tissues were relatively insusceptible to the Gilchrist strain of RV. RV interfered with the growth of vesicular stomatitis virus. Based on this finding, it was possible to develop an assay method in guinea pig tissue cultures by using VSV as the challenge virus. This system appeared to be comparable in sensitivity to the use of primary monkey kidney tissue cultures for the detection of small amounts of RV and offers the advantages of economy, rapidity, and safety.     

Lignin Biosynthesis Studies in Plant Tissue Cultures

Lignin, a phenolic polymer abundant in cell walls of certain cell types, has given challenges to scientists studying its structure or biosynthesis. In plants lignified tissues are distributed between other, non-lignified tissues. Characterization of native lignin in the cell wall has been difficult due to the highly cross-linked nature of the wall components. Model systems, like plant tissue cultures with tracheary element differentiation or extracellular lignin formation, have provided useful information related to lignin structure and several aspects of lignin formation. For example, many enzyme activities in the phenylpropanoid pathway have been first identified in tissue cultures. This review focuses on studies where the use of plant tissue cultures has been advantageous in structural and biosynthesis studies of lignin, and discusses the validity of tissue cultures as models for lignin biosynthesis.     

Tissue Culture Method for Toxigenicity Testing of Corynebacterium diphtheriae

A method for toxigenicity testing of Corynebacterium diphtheriae in tissue cultures was developed. Results were obtained by comparing destruction of the monkey kidney or, preferably, rabbit kidney monolayer by 0.1 ml of the C. diphtheriae culture in Elek's broth containing 20% rabbit serum with the appearance after the addition of 0.2 ml of a mixture of the C. diphtheriae culture and diphtheria antitoxin. The mixture of C. diphtheriae broth culture and 10 antitoxin units per ml was incubated for 1 hr at room temperature before it was added to the tissue cultures which were then incubated as long as 5 days; most results, however, were read in 72 hr. Elek's broth medium was superior to heart infusion broth for toxin production by C. diphtheriae. Addition of 20% rabbit serum improved toxin production in either broth. Numerous toxigenic and atoxigenic C. diphtheriae cultures were tested for toxigenicity in primary rabbit and monkey kidney tissue cultures. If properly controlled, this in vitro method appeared to have an advantage over the in vitro agar gel method; its results were comparable with the rabbit intradermal test. With the wider use of tissue cultures in most laboratories, we believe that the tissue culture method for toxigenicity would be more economical and easier to perform than the animal intradermal method.     

Cryopreservation of Cortical Tissue Blocks for the Generation of Highly Enriched Neuronal Cultures

In this study, we outline a standardized protocol for the successful cryopreservation and thawing of cortical brain tissue blocks to generate highly enriched neuronal cultures. For this protocol the freezing medium used is 10% dimethyl sulfoxide (DMSO) diluted in Hank''s Buffered Salt Solution (HBSS). Blocks of cortical tissue are transferred to cryovials containing the freezing medium and slowly frozen at -1°C/min in a rate-controlled freezing container. Post-thaw processing and dissociation of frozen tissue blocks consistently produced neuronal-enriched cultures which exhibited rapid neuritic growth during the first 5 days in culture and significant expansion of the neuronal network within 10 days. Immunocytochemical staining with the astrocytic marker glial fibrillary acidic protein (GFAP) and the neuronal marker beta-tubulin class III, revealed high numbers of neurons and astrocytes in the cultures. Generation of neural precursor cell cultures after tissue block dissociation resulted in rapidly expanding neurospheres, which produced large numbers of neurons and astrocytes under differentiating conditions. This simple cryopreservation protocol allows for the rapid, efficient, and inexpensive preservation of cortical brain tissue blocks, which grants increased flexibility for later generation of neuronal, astrocyte, and neuronal precursor cell cultures.     

Enzyme histochemistry of human brain tumors and their tissue cultures with special reference to the oxidoreductases in the glioblastoma multiforme

Summary Fresh tissue and tissue cultures of 80 glioblastoma multiforme and 12 monstrocellular sarcoma were histochemically investigated. The activity of the following enzymes was demonstrated in the biopsies and tissue cultures of every tumor: NADH-tetrazolium reductase, NADPH-tetrazolium reductase, lactic dehydrogenase, succinic dehydrogenase, glutamic acid dehydrogenase and cytochrome oxidase. No major differences in the relative activity pattern was shown when fresh tissue and tissue cultures were compared, nor did the enzymatic pattern change during the four week observation time.In both groups major quantitative differences in the enzymatic activity of the tumor cells in the same tissue area or tissue cultures were frequently a striking finding. Differences in the intracellular localization of the enzymatic activity were also observed. In slowly growing gliomas these histochemical variations are absent.     

Chemical and sensory analysis of saffron produced through tissue cultures of Crocus sativus

Stigma-like structures were produced in tissue cultures (TC stigmas) from the ovary explants of C. sativus on MS medium supplemented with NAA and BA. The size of these structures was 2 to 3 cm in length. At higher concentrations of both NAA (54 µM) and BA (44 µM) white tubular abnormal structures were observed from ovary explants in addition to the TC stigmas. Crocin and picrocrocin, responsible for colour and bitter taste respectively, were found to be 6 and 11 times lower in TC stigmas than in the natural stigmas. The saffron obtained from tissue cultures was subjected to sensory analysis and compared with the data obtained from chemical analysis. The sensory data indicated that the saffron pigments produced in tissue cultures were one tenth that of natural stigmas. Sensory profile test showed that the tissue culture saffron was low in floral, spicy and fatty characteristics as compared to saffron obtained from flowers. This is the first report on the sensory analysis of a spice produced in tissue cultures.Abbreviations BA benzyladenine - NAA naphthaleneacetic acid     

Organ Explant Culture of Neonatal Rat Ventricles: A New Model to Study Gene and Cell Therapy

Testing cardiac gene and cell therapies in vitro requires a tissue substrate that survives for several days in culture while maintaining its physiological properties. The purpose of this study was to test whether culture of intact cardiac tissue of neonatal rat ventricles (organ explant culture) may be used as a model to study gene and cell therapy. We compared (immuno) histology and electrophysiology of organ explant cultures to both freshly isolated neonatal rat ventricular tissue and monolayers. (Immuno) histologic studies showed that organ explant cultures retained their fiber orientation, and that expression patterns of α-actinin, connexin-43, and α-smooth muscle actin did not change during culture. Intracellular voltage recordings showed that spontaneous beating was rare in organ explant cultures (20%) and freshly isolated tissue (17%), but common (82%) in monolayers. Accordingly, resting membrane potential was -83.9±4.4 mV in organ explant cultures, −80.5±3.5 mV in freshly isolated tissue, and −60.9±4.3 mV in monolayers. Conduction velocity, measured by optical mapping, was 18.2±1.0 cm/s in organ explant cultures, 18.0±1.2 cm/s in freshly isolated tissue, and 24.3±0.7 cm/s in monolayers. We found no differences in action potential duration (APD) between organ explant cultures and freshly isolated tissue, while APD of monolayers was prolonged (APD at 70% repolarization 88.8±7.8, 79.1±2.9, and 134.0±4.5 ms, respectively). Organ explant cultures and freshly isolated tissue could be paced up to frequencies within the normal range for neonatal rat (CL 150 ms), while monolayers could not. Successful lentiviral (LV) transduction was shown via Egfp gene transfer. Co-culture of organ explant cultures with spontaneously beating cardiomyocytes increased the occurrence of spontaneous beating activity of organ explant cultures to 86%. We conclude that organ explant cultures of neonatal rat ventricle are structurally and electrophysiologically similar to freshly isolated tissue and a suitable new model to study the effects of gene and cell therapy.     

Physiological and biochemical features of embryogenic and non-embryogenic peach palm (<Emphasis Type="Italic">Bactris gasipaes</Emphasis> Kunth) cultures

Both embryogenic and non-embryogenic peach palm (Bactris gasipaes Kunth) cultures arise during somatic embryogenesis induction, and both tissue types are often observed growing side-by-side from the same explant. To better understand why this occurs, samples from each tissue type were analyzed for their endogenous concentrations of indole-3-acetic acid (IAA), abscisic acid (ABA), polyamines, and amino acids with high-performance liquid chromatography and for total phenolics with spectrophotometry. Embryogenic cultures contained significantly higher concentrations of IAA, ABA, and total amino acids, whereas non-embryogenic tissue contained more total polyamines and phenolics. The greater IAA concentrations in embryogenic cultures supported the role of that hormone as a marker of embryogenic potential. Putrescine was especially prevalent in non-embryogenic cultures; however, the decreased putrescine/spermine + spermidine ratio in embryogenic cultures added support to the conclusions of previous studies in other species that this can serve as a marker of embryogenic competence. Though embryogenic cultures contained higher total amino acids, each culture type had different concentrations of specific amino acids.     

Manually and automatically produced pellet cultures of human primary chondrocytes: A comparative analysis

Cartilage defects are often associated with restriction of the locomotor system. New methods are required to investigate cartilage tissue and for the repair of cartilage tissue. 3D cultures are promising due to better simulation of in vivo conditions. The aim of this study was to provide a model system for studying cartilage tissue. We solved this problem by automated production of pellet cultures of human primary chondrocytes in media with and without antibiotics using the Biomek® Cell Workstation and consequent automated bioscreening with a high‐throughput screening system, and compared with the regular manual processes. The Biomek® Cell Workstation allows the cultivation of different cell types (suspensions cells and adherent cells) and 3D cell cultures (pellet cultures, alginate beads and spheroid cultures). The proliferation was analyzed by DNA quantification and compared with the EZ4U proliferation assay as a new tool for pellet cultures. The toxicity was evaluated by the detection of ubiquitous adenylate kinases. The proliferation increased from day 14 until day 35 and was associated with a decrease in the cytotoxicity. The comparative analysis showed similar results for manual and automated processes. We concluded that the manual methods can be replaced by automated processes (pellet manufacturing and screening), which would allow large‐scale procedures to support studies on cartilage regeneration.     

Plasmid profiles of Lactobacillus plantarum spp. found as contaminants in Hemerocallis plant tissue cultures

Plasmid profiles of 30 strains of Lactobacillus plantarum isolated from 3-year-old tissue cultures and surface sterilized stem sections of glasshouse grown plants of three different varieties of Hemerocallis were compared to pinpoint the source of Lact. plantarum contamination in plant tissue cultures. Since the profiles of strains isolated from in vitro and in vivo plant material were generally identical, it is thought that the source of Lact. plantarum contamination is the plant material used to initiate plant tissue cultures.     

Purine Alkaloid Production and Accumulation in Cocoa Callus and Suspension Cultures

Cocoa callus and suspension cultures were found to produce caffeine,theobromine, and theophylline which are typical of the purinealkaloids found in cocoa beans. Production of these purine alkaloidswas monitored in callus cultures for over 2 years and shownto stabilize at concentrations of about 10% those found in vivo.Caffeine and theobromine were produced concomitant with logphase growth of the cultures whilst theophylline productionreached a maximum during stationary phase, reflecting the possiblerole of the latter as a catabolite of caffeine. The effectsof choice of cytokinin, explant tissue, cocoa type, light conditionsand time in culture on purine alkaloid production by callushave been examined. Purine alkaloid production by cocoa suspensioncultures has also been examined and these cultures were shownto be less productive and more variable than callus cultures.The results demonstrate that cocoa tissue cultures can be usefulfor studying secondary metabolism in vitro. Key words: Theobroma cacao, caffeine, theobromine, tissue culture, secondary metabolism     

Sulfated proteoglycan synthesis by confluent cultures of rabbit costal chondrocytes grown in the presence of fibroblast growth factor

We examined the effect of fibroblast growth factor (FGF) on proteoglycan synthesis by rabbit costal chondrocyte cultures maintained on plastic tissue culture dishes. Low density rabbit costal chondrocyte cultures grown in the absence of FGF gave rise at confluency to a heterogeneous cell population composed of fibroblastic cells and poorly differentiated chondrocytes. When similar cultures were grown in the presence of FGF, the confluent cultures organized into a homogenous cartilage-like tissue composed of rounded cells surrounded by a refractile matrix. The cell ultrastructure and that of the pericellular matrix were similar to those seen in vivo. The expression of the cartilage phenotype in confluent chondrocyte cultures grown from the sparse stage in the presence vs. absence of FGF was reflected by a fivefold increase in the rate of incorporation of [35S]sulfate into proteoglycans. These FGF effects were only observed when FGF was present during the cell logarithmic growth phase, but not when it was added after chondrocyte cultures became confluent. High molecular weight, chondroitin sulfate proteoglycans synthesized by confluent chondrocyte cultures grown in the presence of FGF were slightly larger in size than that produced by confluent cultures grown in the absence of FGF. The major sulfated glycosaminoglycans associated with low molecular weight proteoglycan in FGF-exposed cultures were chondroitin sulfate, while in cultures not exposed to FGF they were chondroitin sulfate and dermatan sulfate. Regardless of whether or not cells were grown in the presence or absence of FGF, the 6S/4S disaccharide ratio of chondroitin sulfate chains associated with high and low molecular weight proteoglycans synthesized by confluent cultures was the same. These results provide evidence that when low density chondrocyte cultures maintained on plastic tissue culture dishes are grown in the presence of FGF, it results in a stimulation of the expression and stabilization of the chondrocyte phenotype once cultures become confluent.     

The cytogenetic, proliferative and viability effects of four bacteriophages on human lymphocytes

Certain bacteriophages have been found in live virus vaccines, while a few others have been associated with disease states. Some of these phages have produced abnormal growth of eukaryotic tissue cultures. For this reason bacteriophages phiX-174, MS2, T2 and an isolate from live virus vaccines, phiV-1, were incubated with human cell cultures for examination of chromosomal effects, cell proliferation and viability. Mitogen-stimulated lymphocytes and human embryonic kidney tissue cultures showed no increase in chromosomal abnormalities for high doses of phage-infected versus control cultures. Tritiated-thymidine uptake, correlated with mitotic indices for phage-treated lymphocyte cultures, indicated a reduction in cell division, while 51-chromium release studies showed no cell death occurring in these cultures. This suggested that inhibition of DNA synthesis was occurring in some cells. The presence of phage in the supernate of cells that were exposed to phage suggested the possibility of phage attachment to the plasma membranes of lymphocytes, which may in turn affect the suppression of DNA synthesis.     

Chitinase production in pine callus (<Emphasis Type="Italic">Pinus sylvestris</Emphasis> L.): a defense reaction against endophytes?

In shoot tip-derived tissue cultures of Scots pine (Pinus sylvestris L.), browning and subsequent degeneration of the culture is accompanied by lipid peroxidation and lignification of cells, which are characteristic features of a plant defense reaction. Since chitinases are enzymes acting primarily in plant defense, their expression was studied in pine callus in order to elucidate the defense reaction. Chitinases were present diversely in tissue cultures originating from shoot tips and embryos of P. sylvestris, in contrast to Pinus nigra embryogenic callus, where production of chitinases or browning was not detected. Because endophytic microbes had earlier been detected in buds of Scots pine, their subsequent presence in the tissue cultures was considered a potential cause of the defense reaction. Therefore, the presence of endophytes in the tissue cultures was examined by in situ hybridization. Endophytes were found to colonize heavily in 45% of the tissue cultures of P. sylvestris and to form biofilms, while the P. nigra callus was not found to contain any microbes. The endophytes seemed to propagate uncontrollably once a tissue culture of P. sylvestris was initiated. Regardless of the high level of chitinase production in the callus, the control of the endophytes presumably becomes inadequate during the tissue culture of P. sylvestris.