Clear suppression of Th1 responses but marginal amelioration of autoimmune manifestations by IL-12p40 transgene in MRL-FAS(lprcg)/FAS(lprcg) mice

To investigate the effects of overproduction of IL-12p40, a potent antagonist against IL-12, on lupus-like autoimmune disease in vivo, we generated p40 transgenic MRL-Fas(lprcg)/Fas(lprcg) mice. Serum p40 and IL-12 levels were 600- to 8000-fold and 3- to 20-fold higher in transgenic (p40-lpr(cg)) than nontransgenic (lpr(cg)) mice, respectively. Serum IFN-gamma levels increased after 3 months of age in lpr(cg) and this age-related increase was completely abrogated in p40-lpr(cg). Serum IL-4 levels were the same in both mice. Production of IgM and IgG anti-double-stranded DNA (dsDNA) antibodies was significantly lower in p40-lpr(cg). Anti-dsDNA antibodies decreased in Th1-dependent IgG2a but increased in the Th2-dependent IgG1 subclass significantly in p40-lpr(cg). Proteinuria, glomerulonephritis, and survival were only marginally ameliorated in p40-lpr(cg). The results suggest that excess p40 production in vivo may suppress Th1 responses in autoantibody and IFN-gamma production but lead to minimal improvement of clinical manifestations of autoimmune disease in this mouse model.     

Immunological evaluation of repeated administration of erythrocyte-entrapped protein to C3H/HeJ mice.

The immunogenicity of heterologous protein entrapped in autologous erythrocytes was evaluated in a mouse system. Multiple intravenous administrations of an erythrocyte-entrapped bovine beta-glucuronidase preparation resulted in little, if any, immunological response to the entrapped protein or erythrocyte carrier. Erythrocyte entrapment also protected protein from circulating antibody elicited by prior subcutaneous sensitization with unentrapped enzyme in adjuvant. Thus erythrocyte entrapment may protect potentially immunogenic agents from immunological surveillance.     

Differing signal requirements for the activation of macrophages from C3H/HeJ and C3H/OuJ mice

Abstract Endotoxin-associated protein (EP) from Salmonella typhi stimulated the release of prostaglandin E2 (PGE2), interleukin-1 (IL-1), and interferon (IFN) activity in macrophages from the lipopolysaccharide (LPS) responder C3H/OuJ mouse strain. However, only PGE2 and IL-1 were stimulated by EP in macrophages from the LPS nonresponder C3H/HeJ mouse strain. LPS stimulated the release of PGE2, IL-1 and IFN activity in C3H/OuJ macrophages, but not in C3H/HeJ macrophages. The protein kinase C (PKC) activator phorbol myristic acid (PMA) stimulated PGE2 production in both strains but not IL-1 production, suggesting that signalling pathways other than PKC may be involved in IL-1 production. The calcium ionophore ionomycin stimulated PGE2 production in C3H/OuJ but not C3H/HeJ macrophages, suggesting a defective calcium-related pathway in the C3H/HeJ macrophages as compared to the C3H/OuJ cells.     

Forestomach ulcers in Crj:B6C3 (C57BL/6NCrj x C3H/HeNCrj) F1 mice

An unusually high incidence of forestomach ulcers was observed in a mouse strain that is used frequently for long-term toxicology studies. Examination of 98 untreated male and 98 untreated female B6C3F1 hybrid mice, the majority of which were between 105 and 113 weeks of age, revealed forestomach ulcers in 52% of the males and 54% of the females. Glandular stomach ulcers were uncommon, being found in only four female mice. The incidence of the ulcers increased with age. The etiology of the lesion is unknown.     

无菌级C3H/OrlSlac小鼠生长繁殖、主要脏器参数以及血液生理生化指标的测定分析

目的了解无菌级C3H/OdSlac小鼠的生长、繁殖性能;测定无菌级C3H/OrlSlac小鼠主要脏器重量以及血液生理、生化正常值并进行分析比较.方法 ①统计无菌级C3H/OrlSlae小鼠的1～3胎的繁殖指标数据,包括:平均每胎产子数、离乳率、怀孕率、胎间隔和生产指数;②分别称取60只(雌雄各半)0～112 d的无菌级...     

Assimilatory sulfate reduction in C(3), C(3)-C(4), and C(4) species of Flaveria

The activity of the enzymes catalyzing the first two steps of sulfate assimilation, ATP sulfurylase and adenosine 5'-phosphosulfate reductase (APR), are confined to bundle sheath cells in several C(4) monocot species. With the aim to analyze the molecular basis of this distribution and to determine whether it was a prerequisite or a consequence of the C(4) photosynthetic mechanism, we compared the intercellular distribution of the activity and the mRNA of APR in C(3), C(3)-C(4), C(4)-like, and C(4) species of the dicot genus Flaveria. Measurements of APR activity, mRNA level, and protein accumulation in six Flaveria species revealed that APR activity, cysteine, and glutathione levels were significantly higher in C(4)-like and C(4) species than in C(3) and C(3)-C(4) species. ATP sulfurylase and APR mRNA were present at comparable levels in both mesophyll and bundle sheath cells of C(4) species Flaveria trinervia. Immunogold electron microscopy demonstrated the presence of APR protein in chloroplasts of both cell types. These findings, taken together with results from the literature, show that the localization of assimilatory sulfate reduction in the bundle sheath cells is not ubiquitous among C(4) plants and therefore is neither a prerequisite nor a consequence of C(4) photosynthesis.     

Chromosomal inversion discovered in C3H/HeJ mice

Mice of the inbred mouse strain C3H/HeJ have been shown to be homozygous for a chromosomal inversion on Chromosome (Chr) 6. The inversion encompasses about 20% of the chromosome from approximately 73 Mb to approximately 116 Mb. The importance of this finding is that linkage crosses using C3H/HeJ will show no recombination in this region of Chr 6. The inversion has no apparent effect on the phenotype of C3H/HeJ mice and its presence should not affect biological studies; however, use of C3H/HeJ mice for genetic analysis of Chr 6 should be avoided or the results interpreted with the inversion in mind. The inversion has been named In(6)1J (inversion Chr 6, Jackson 1).     

Marker-assisted congenic screening (MACS): A database tool for the efficient production and characterization of congenic lines

Over the past decades, genetic studies in rodent models of human multifactorial disorders have led to the detection of numerous chromosomal regions associated with disease phenotypes. Owing to the complex control of these phenotypes and the size of the disease loci, identifying the underlying genes requires further analyses in new original models, including chromosome substitution (consomic) and congenic lines, derived to evaluate the phenotypic effects of disease susceptibility loci and fine-map the disease genes. We have developed a relational database (MACS) specifically designed for the genetic marker-assisted production of large series of rodent consomic and congenic lines (speed congenics), the organization of their genetic and phenotypic characterizations, and the acquisition and archiving of both genetic and phenotypic data. This database, originally optimized for the production of rat congenics, can also be applied to mouse mapping projects. MACS represents an essential system for significantly improving efficiency and accuracy in investigations of multiple consomic and congenic lines simultaneously derived for different disease loci, and ultimately cloning genes underlying complex phenotypes.     

The lymphatic pathology of Brugia pahangi in nude (athymic) and thymic mice C3H/HeN

The nude (congenitally athymic) mouse, C3H/HeN is highly susceptible to infection with Brugia pahangi (Nematoda: Filarioidea). Normal, hairy mice show a strong thymus-dependent resistance and usually terminate the infection in the larval stages. The present study examined chronological histopathologic changes in the lumbar lymph nodes and adjacent lymphatic vessels of both hosts. In thymic mice, lymphangitis and perilymphangitis reached a maximum 14 to 17 days PI, about the time of disappearance of live worms. The infiltrate showed characteristics of both acute and chronic inflammation: eosinophils, neutrophils, eosinophilic precipitates, and sometimes necrotizing lymphangitis, as well as macrophages and plasma cells. The cellular infiltrate in nude mice was weaker and developed more slowly. Inflammatory responses to identifiable dead worms were seen in both types of hosts but appeared more frequently in thymic mice. Although variable in both models, the granulomas of thymic mice generally showed more tendency to cavitation, greater macrophage or epithelioid cell infiltration, more granulocytes, and appeared to be more destructive than the foreign body responses of nude mice. Whereas lymphangiectasis was generally progressive in nude mice, it was arrested before the end of the third week in thymic mice. In thymic mice, at maximum lumbar lymph node size (17 days), there were large areas of lymphocyte hyperplasia and heavy infiltration of plasma cells. Most nodes returned to normal mean size by the end of the second month. Little or no reactivity was seen in athymic mouse nodes. Our results suggest that some lesions of lymphatic filariasis are potentially thymus-independent: lymphatic fibrosis, lymphangiectasis, accumulations of macrophages and giant cells around disintegrating worms, calcification of worms, intralymphatic thrombosis, and moderate vascular infiltrates including eosinophils.     

A search for interstellar oxiranecarbonitrile (C3H3NO)

We report a search in cold, quiescent and in hot core type interstellar molecular clouds for the small cyclic molecule oxiranecarbonitrile (C₃H₃NO), which has been suggested as a precursor of important prebiotic molecules. We have determined upper limits to the column density and fractional abundance for the observed sources and find that, typically, the fractional abundance by number relative to molecular hydrogen of C₃H₃NO is less than a few times 10^–10. This limit is one to two orders of magnitude less than the measured abundance of such similarly complex species as CH₃CH₂CN and HCOOCH₃ in well-studied hot cores. A number of astrochemical discoveries were made, including the first detection of the species CH₃CH₂CN in the massive star-forming clouds G34.3+0.2 and W51M and the first astronomical detections of some eight rotational transitions of CH₃CH₂CN, CH₃CCH, and HCOOCH₃. In addition, we found 8 emission lines in the 89 GHz region and 18 in the 102 GHz region which we were unable to assign.     

Antileishmanial activities of macrophages from C3H/HeN and C3H/HeJ mice treated with Mycobacterium bovis strain BCG

C3H/HeN and C3H/HeJ mice were infected ip with viable BCG, a macrophage-activating agent, and their peritoneal exudate macrophages exposed to Leishmania tropica amastigotes. Macrophages from BCG-infected C3H/HeN mice had both leishmanicidal activities described for lymphokine activation of C3H/HeN macrophages in vitro: increased resistance to L. tropica infection, followed by intracellular killing of the parasite. Macrophages from BCG-infected C3H/HeN mice were also activated to kill tumor cells in vitro. In contrast, macrophages from BCG-treated C3H/HeJ mice were not resistant to L. tropica infection, did not kill intracellular amastigotes over 72 hr in culture, and were not cytotoxic to tumor cells.     

Defective tumoricidal capacity of macrophages from C3H/HeJ mice

Peritoneal macrophages from C3H/HeN mice treated i.p. with T cell mitogens or viable BCG organisms were cytotoxic to syngeneic tumor cells in vitro. Macrophages from endotoxin-unresponsive C3H/HeJ mice treated with BCG or T cell mitogens, however, were not tumoricidal. Furthermore, unlike cells from C3H/HeN mice, macrophages from C3H/HeJ mice could not be activated for tumor cytotoxicity after in vitro treatment with bacterial endotoxins or with lymphokine-rich supernatants. The subnormal induction of cytotoxic macrophages after in vitro or in vivo treatments in C3H/HeJ mice appears to be a highly selective defect. Macrophage responses (yield, phagocytosis, or peroxidase staining) in inflammatory exudates induced by BCG, T cell mitogens, or heterologous serum in C3H/HeJ or C3H/HeN mice were identical. C3H/HeJ macrophages also responded normally in vitor to chemotactic lymphokines. Thus, C3H/HeJ macrophages possess a profound and selective defect in tumoricidal capacity. This defect was not dependent upon exogenous endotoxins. Defective macrophage cytotoxic responses may reflect non-LPS related functions regulated by the LPS gene.     

Lymphocytes from H2 mice produce lower levels of several cytokines than congenic H2 or H2 mice

Inbred mice of congenic strains that differ only in their H2 haplotype were used to examine the effects of MHC genes on production of cytokines. Spleen and lymph node cells were stimulated with mitogens in vitro, and cytokine protein was assessed by ELISA and/or bioassays. Cells from H2b mice synthesized less IL-3, IL-4, IL-5, TNF and IL-10 (less clearly) than the equivalent cells from H2k or H2d mice. Production of IL-6 by H2b spleen and lymph node cells was lower than that by cells from H2d mice. In addition, lower lymphoproliferative responses were observed in lymph node cultures from H2b mice. These effects were evident in congenic B10 and BALB strains. B10 H2b mice stimulated in vivo with anti-CD3 had lower levels of IFN-gamma and IL-5 protein in their serum compared with equivalent H2k and H2d mice. Because class I- or II-mediated antigen presentation was not required in our model, an immunoregulatory gene in the central MHC is implicated. Preliminary studies of MHC recombinant mice suggested that the gene or genes responsible lie telomeric of IEbeta. Evidence that the H2b haplotype carries an immunoregulatory allele with a small but consistent effect on cytokine production warrants further investigation.     

Synthesis and characterization of two isomers of Os3(CO)10(C5H4N-2-C(H)NR) and the conversion to ortho-metallated HOs3(C5H3N-2-C(H)NR)(CO)9. Part III. X-ray Structure of HOs3(C5H3N-2-C(H)Ni-Pr)(CO)9

Os₃(CO)₁₀(MeCN)₂ reacts at room temperature in MeCN or toluene with R-Pyca2 to yield two isomers of Os₃(CO)₁₀(R-Pyca) that differ in the bonding of the R-Pyca ligand to the Os₃(CO)₁₀ unit. In all cases Os₃(CO)₁₀(R-Pyca(4e)) (isomer A; 4a: R = c-Pr, 4b: R = i-Pr, 4c: R = neo-Pent, 4d: R = t-Bu), containing a chelating 4e donating R-Pyca ligand and three OsS bonds, could be isolated. In the case of R = c-Pr and R = i-Pr Os₃(CO)₁₀(R-Pyca(6e)) (isomer B; 5a: R = c-Pr, 5b: R = i-Pr), in which only two OsS bonds are present and the R-Pyca ligand is bonded as a 6e donating ligand bridging two non-bonded Os atoms, could be isolated as a minor product.At 70 °C Os₃(CO)₁₀(R-Pyca(4e)) (4b and 4d) loses one carbonyl and the pyridine moiety of the R-Pyca ligand is ortho-metallated to form HOs₃(C₅H₃N-2-C(H)NR)(CO)₉ (6b: R = i-Pr and 6d: R = t-Bu). Under the same conditions Os₃(CO)₁₀(i-Pr-Pyca(6e)) (5b) reacts to Os₂(CO)₆(6e)) (7b) containing a bridging 6e donating ligands. The latter two reactions were followed with FT-IR spectroscopy in a high temperature IR cell.The structure of the complexes in solution have been studied by ¹H and ¹C NMR and IR spectroscopy. The stoichiometries of 4a and 5a were determined by FAB-mass spectrometry while an exact mass determination was carried out for 4a.The crystal structure of 6b has been determined. Crystal of 6b are monoclinic, space group P2₁/n, with a = 7.808(2),b = 17.613(3),c = 16.400(8)Å, β = 94.09(3)° and Z = 4. The structure was refined to R = 0.039. The molecule contains a triangular array of osmium atoms [Os(1)Os(2) = 2.898(2)Å, Os(1)Os(3) = 2.886(2)Åand Os(2)O(3) = 2.911(2)Å] and nine terminally bonded carbonyl ligands. The C₅H₃N-2-C(H)N-i-Pr ligand is chelate bonded to Os(2) with the pyridine and imine nitrogens atoms axially and equatorially coordinated respectively [Os(2)N(1) = 2.00(2)Åand Os(2)N(2) = 2.11(2)Å]. The i-Pr-Pyca ligand is ortho-metallated at C(1) and forms a four membered ring containing Os(2), Os(3), C(1) and N(1), the Os(3)C(1) distance being 2.12(2)Å. The hydride, which could not be located unequivocally from a difference Fourier map is proposed to bridge the Os(2)(3) bond on the basis of stereochemical considerations.