Re-examination ofPyrenomonas andRhodomonas (class cryptophyceae) through ultrastructural survey of red pigmented cryptomonads

Several taxa of cryptomonads, including species of marineChroomonas, Cryptomonas and freshwaterRhodomonas were examined using transmission electron microscopy. They have cellular structures fundamentally in common: a single bilobed chlorplast, a single pyrenoid between the chloroplast lobes, and a nuclemorph embedded within a cleft of the pyrenoidal matrix. These features are in accordance with the taxonomic characteristics of the recently established genusPyrenomonas. The algae also have similar pigmentation to that ofRhodomonas andPyrenomonas which is red or reddish-brown. On the basis of these observations, the genusRhodomonas Karsten (1898) is redescribed in this paper and the genusPyrenomonas Santore is considered to be synonymous withRhodomonas.     

Differential regulation of the low affinity Fc receptor for IgE (Fc epsilon R2/CD23) and the IL-2 receptor (Tac/p55) on eosinophilic leukemia cell line (EoL-1 and EoL-3)

Two types of activation Ag, low affinity FcR for IgE (Fc epsilon R2)/CD23 and IL-2R (Tac/p55), were expressed and differently regulated on human eosinophilic leukemia cell lines (EoL-1 and EoL-3). Because the binding of IgE on EoL-3 cells was completely inhibited by H107 (anti-Fc epsilon R2/CD23 mAb) but not by irrelevant mAb, essentially all the low affinity Fc epsilon R2 on EoL-3 seemed to be the Fc epsilon R2/CD23 molecules. Both IL-4 and IFN-gamma enhanced the surface expression of Fc epsilon R2, whereas IL-1, IL-2, and IL-5 showed no effects, as determined by surface staining with anti-Fc epsilon R2 antibody (H107). In contrast to Fc epsilon R2 up-regulation, IL-4 and IFN-gamma showed a differential effect on the regulation of IL-2R (Tac/p55). Whereas IFN-gamma up-regulated the receptor expression of IL-2R/Tac, IL-4 did not. The result suggests that these lymphokines are involved in the different aspects of the activation pathway of the eosinophils. The possible role of Fc epsilon R2 and IL-2R on the function of eosinophils in allergic reaction is discussed.     

Harderianization is another sexual dimorphism of rat exorbital lacrimal gland

The exorbital lacrimal glands (ELG) of rats were examined for both sexes to determine what degree of harderianization occurred as a function of age and after castration, and to investigate its time course and origin in ELG. Light microscopically, very small Harderian foci were seen in the ELG of both sexes at 3 weeks of age. As the male rats became older, the relative volume of the Harderian gland (HG) cells in the ELG increased. At age 6 months, the value was 1.25 +/- 0.31% in males and 0.13 +/- 0.05% in females (p less than 0.05). After castration, a significant decrease (0.21 +/- 0.01%, p less than 0.05) was observed in that of male ELG. In contrast, in female ELG, HG cells were inconspicuous and the relative volume of those did not vary during this experimental period or after castration. It appeared that the HG cells had developed from undifferentiated basal cells of the acini and the intercalated ducts in the ELG at age 2-6 months. Then, at age 22 months, they also probably developed from those of the excretory ducts of the ELG.     

The effect of bispecific monoclonal antibody recognizing both hepatoma-specific membrane glycoprotein and anthracycline drugs on the metastatic growth of hepatoma AH66

A monoclonal mouse antibody (MoHG) was produced using in vitro cultured AH66R tumor cells treated with cholesteryl hemisuccinate as an immunogen. The antibody identified a 90 kd membrane glycoprotein (HG-90) which is expressed on in vitro cultured hepatoma cell lines AH66 and AH66R. A monoclonal antibody was prepared to the anthracycline drug daunomycin, and it also reacted with adriamycin. A fusion was made of the hybridoma HG-90 with the hybridoma which recognized daunomycin/adriamycin. This bispecific hybridoma A8C recognized both determinants. We studied the therapeutic effect of the A8C bispecific antibody with adriamycin treatment and compared it to the effect of the bispecific antibody to which adriamycin had been conjugated via an albumin (Alb) bridge. The therapy model used was the tumor AH66R in Donryu rats. Tumor bearing rats had their subcutaneous tumors resected on day 10, a time when distant metastases were present. After the surgical resection of the tumor the rats were injected intravenously for two cycles with the bispecific antibodies, followed by the administration of adriamycin (ADR) or MoHG.Alb.ADR conjugates. A slight therapeutic effect occurred with either MoHG or ADR alone but treatment with the bispecific antibody followed by the administration of ADR or with the MoHG.Alb.ADR conjugates significantly prolonged survival, with 60% of the treated animals being "tumor free" when sacrificed on day 80. Lower serum concentrations of alphafetoprotein were observed with the bispecific antibody and drug treatment. This suggests that the bispecific antibody/drug treatment is potentially more beneficial in the suppression of distant metastases than the MoHG.Alb.ADR conjugate. This may be due to an increase in the local drug concentration of unmodified adriamycin.     

Comparison of enzyme phenotypes in human bladder tumours and experimentally induced hyperplastic and neoplastic lesions of the rat urinary bladder. A combined histochemical and immunohistochemical approach

The expression of a number of enzymes involved in drug metabolism, membrane function etc. was compared in hyperplastic and neoplastic lesions of the rat bladder and in human bladder tumours. Transitional cell carcinomas (TCC) in both rat and Man were characterized by decreased alkaline phosphatase (ALP) and increased gamma-glutamyl transpeptidase (GGT), beta-glucuronidase (beta-G1), succinate dehydrogenase (SD) and glucose-6-phosphate dehydrogenase (G6PD) activities. In addition, binding for antibodies specific for different cytochrome P-450 species (UT50, PB3a, MC1, MC2) and microsomal epoxide hydrolase (mEHb) was elevated in both murine and human tumours. Comparison of the enzyme phenotype in hyperplastic lesions induced by freeze ulceration or uracil administration with that in preneoplastic papillary or nodular hyperplasia (PNH) and TCC suggested, however, that most of the alteration in enzyme content or activity was non-specific and related to requirements for epithelial cell proliferation. On the other hand, the decreased ALP, and increased GGT and beta-G1 activity appeared more directly related to neoplastic transformation. The results suggested that qualitative differences exist between reactive hyperplasia and preneoplastic or neoplastic lesions in the urinary bladder. The finding of increased cytochrome P-450, in clear contrast to the reduction characteristic of preneoplastic hepatic lesions, may be important with regard to the observed difference in neoplastic transformation between the bladder and liver in response to drug metabolising enzyme inducers.     

In vivo and in vitro synergistic antitumor effect of interleukin-2-cultured tumor-bearer spleen cells and immune fresh spleen cells

Summary The synergistic antitumor effect of interleukin-2(IL-2)-cultured tumor-bearer spleen cells (cultured lymphocytes) and immune fresh spleen cells was examined. Tumor-bearer cultured lymphocytes were obtained by culturing BALB/c spleen cells from syngeneic MOPC104E-tumor-bearing mice for 11 days with crude IL-2 and a soluble tumor extract. These cultured lymphocytes had weak antitumor activity when transferred i.p. into tumor-bearing mice that had been inoculated i.p. with 10⁵ tumor cells 5 days previously. Immune fresh spleen cells, obtained from mice in complete remission after the treatment with cyclophosphamide, also had weak antitumor activity when transferred at the same schedule. The cultured cells and the fresh cells, mixed together before transfer, significantly augmented the therapeutic effect. At least 1×10⁷ tumor-bearer cultured lymphocytes and 4×10⁷ immune cells were needed for the synergistic effect. A tumor-specific combination was needed for both cultured and fresh cells. The effective subpopulation of tumor-bearer cultured lymphocytes was a cytotoxic one from an Lyt2⁺ precursor, and that of the immune fresh spleen cells was noncytotoxic, Lytl⁺ and Lyt2⁺ T-cells.A similar synergistic effect was also observed during in vitro coculture of tumor-bearer and immune cells. Cytotoxicity, as assessed by the ⁵¹Cr-release test, of tumor-bearer IL-2-cultured lymphocytes was maintained most effectively after 3 or 4 days of culture without IL-2 when the lymphocytes were cocultured with immune fresh spleen cells and tumor cells.     

Metabolism of exogenous galactosylceramide in the twitcher mouse brain

The in vivo metabolism of galactosylceramide (gal-cer) in normal mice and in twitcher mice, a model of human GLD, was examined following intracerebral administration of gal-cer containing [1-¹⁴C]stearic acid. In normal mice, gal-cer was hydrolyzed to ceramide within 6 hours and ceramide was hydrolyzed to sphingosine and fatty acid. Most of the released fatty acid was immediately incorporated into other lipids. About 75% of injected gal-cer was hydrolyzed 80 hours after the injection, while in the twitcher mouse, only 17% of gal-cer was hydrolyzed. These results show that degradation of gal-cer is impaired in the twitcher mouse brain, but contradict to the fact that there was no evidence of any accumulation of gal-cer in the brain. This discrepancy may be due to the different sorting routes of biosynthesized and exogenously-administered gal-cer in the mouse brain. Most of the biosynthesized gal-cer is incorporated into myelin, while the injected gal-cer is incorporated into lysosomes.     

The purification and properties of NADPH-dependent carbonyl reductases from rat ovary

Two carbonyl reductases have been highly purified from rat ovary to apparent homogeneity. Though they have similarities in terms of molecular weight (33,000), substrate specificities, inhibitor sensitivities, amino acid composition, and immunological properties, they differed in pI values (6.0 and 5.9). Both enzymes reduced aromatic aldehydes, ketones, and quinones at higher rates, compared to prostaglandins and 3-ketosteroids, whereas they showed higher affinity for prostaglandins and 3-ketosteroids. The enzymes also catalyzed oxidation of the 9-hydroxy group of prostaglandin F2 alpha. Moreover, they showed the remarkable characteristic of catalyzing the reduction of not only the 9-keto group of prostaglandin E2 but also the 15-keto group of 13,14-dihydro-15-keto-prostaglandin F2 alpha. Both enzymes were inhibited by SH-reagents, quercitrin, indomethacin, furosemide, and disulfiram. The results of immunoinhibition, using antibody against the purified enzymes, indicated that the enzymes were solely responsible for the overall catalytic activities of prostaglandin E series reduction, as well as 13,14-dihydro-15-keto-prostaglandin F2 alpha reduction and prostaglandin F2 alpha oxidation in rat ovarian cytosol. Western-blot analysis revealed that immunoreactive proteins were present in adrenal gland and various reproductive tissues except uterus of rats.