Macrophage cell-conditioned medium promotes cholinergic differentiation of undifferentiated progenitors and synergizes with nerve growth factor action in the developing basal forebrain

Conditioned medium from stimulated microglia and from the monocyte/macrophage cell line (RAW 264.7; MC-CM) promotes the differentiation of cholinergic neurons from undifferentiated progenitors in the septal nuclei and adjacent basal forebrain (BF). We have studied the regulation of this process by measuring the activity of choline acetyltransferase (ChAT) in cultured BF taken from embryonic day 16 rat brain. Inhibition of either xanthine oxidase with allopurinol or nitric oxide synthase with N(G)-monomethyl-l-arginine produces a small but significant improvement in the efficacy of MC-CM while inclusion of pyrrolidine dithiocarbamate, a hydroxyl radical scavenger widely used as an antioxidant, lowers MC-CM-induced ChAT activity. Addition of nerve growth factor (NGF) but not brain-derived neurotrophic factor or glial-derived neurotrophic factor together with MC-CM has a synergistic effect on both ChAT activity and ChAT mRNA, raising ChAT activity as much as 29-fold and ChAT mRNA almost 15-fold. While MC-CM raised mRNA for trkA, the effect was not synergistic with NGF. mRNA for the common neurotrophin receptor (p75NTR) showed a modest synergistic increase. Blockade of the Ras/Raf/ERK [extracellular signal-regulated kinase, also known as mitogen-activated protein [(MAP) kinase] signal transduction pathway with either PD28059 (an inhibitor of MAP kinase/ERK kinase kinase or MEK) or N-acetyl-S-farnesyl-l-cysteine (an inhibitor of Ras farnesylation and, hence, activation) inhibited the action of MC-CM. Moreover, a subpopulation of cells responded rapidly to MC-CM with an increased appearance of phosphorylated ERK. Because NGF also utilizes this pathway, synergy may occur along this signal transduction pathway.

Enhanced immune response to the melanoma antigen gp100 using recombinant adenovirus-transduced dendritic cells

Glycoprotein 100 (gp100) is one of a series of well-characterized human melanoma-associated antigens expressed by most melanoma cells. Immunization of C57BL/6 mice with an adenovirus (Ad) vector encoding human gp100 (Adhgp100) has been shown to induce limited protective immunity against challenge with murine melanoma B16 cells. In the current study we determined whether gp100-specific immunity can be enhanced using bone-marrow-derived dendritic cells (DCs) transduced with Adhgp100 ex vivo. Subcutaneous injection of Adhgp100-infected DCs resulted in potent T-cell-mediated protective immunity and a greater than 80% reduction of established tumors when administered to B16 tumor-bearing hosts. Compared to direct injection of Adhgp100 vector alone, immunization with Adhgp100-infected DCs induced markedly greater antitumor activity. In vitro CTL analysis demonstrated that DC-Adhgp100 immunization activated both CD4(+) and CD8(+) CTLs, while no lytic activity was generated by vaccination with Adhgp100 alone. In vivo depletion of CD4(+) T cells, but not CD8(+) T cells, completely abrogated CTL activity, suggesting that Adhgp100-transduced DCs result in activation of both CD4(+) and CD8(+) CTLs via a CD4(+)-dependent mechanism. We speculate that this improved efficacy of Adhgp100-transduced DCs compared to direct immunization with Adhgp100 may be the result of direct DC-mediated CD4(+) T cell activation. These results emphasize the importance of CD4(+) T cells in the development of therapeutic antigen-specific cancer vaccines.

High-monounsaturated fatty acid diets lower both plasma cholesterol and triacylglycerol concentrations

BACKGROUND

Low-fat diets increase plasma triacylglycerol and decrease HDL-cholesterol concentrations, thereby potentially adversely affecting cardiovascular disease (CVD) risk. High-monounsaturated fatty acid (MUFA), cholesterol-lowering diets do not raise triacylglycerol or lower HDL cholesterol, but little is known about how peanut products, a rich source of MUFAs, affect CVD risk.

OBJECTIVE

The present study compared the CVD risk profile of an Average American diet (AAD) with those of 4 cholesterol-lowering diets: an American Heart Association/National Cholesterol Education Program Step II diet and 3 high-MUFA diets [olive oil (OO), peanut oil (PO), and peanuts and peanut butter (PPB)].

DESIGN

A randomized, double-blind, 5-period crossover study design (n = 22) was used to examine the effects of the diets on serum lipids and lipoproteins: AAD [34% fat; 16% saturated fatty acids (SFAs), 11% MUFAs], Step II (25% fat; 7% SFAs, 12% MUFAs), OO (34% fat; 7% SFAs, 21% MUFAs), PO (34% fat; 7% SFAs, 17% MUFAs), and PPB (36% fat; 8% SFAs, 18% MUFAs).

RESULTS

The high-MUFA diets lowered total cholesterol by 10% and LDL cholesterol by 14%. This response was comparable with that observed for the Step II diet. Triacylglycerol concentrations were 13% lower in subjects consuming the high-MUFA diets and were 11% higher with the Step II diet than with the AAD. The high-MUFA diets did not lower HDL cholesterol whereas the Step II diet lowered it by 4% compared with the AAD. The OO, PO, and PPB diets decreased CVD risk by an estimated 25%, 16%, and 21%, respectively, whereas the Step II diet lowered CVD risk by 12%.

CONCLUSION

A high-MUFA, cholesterol-lowering diet may be preferable to a low-fat diet because of more favorable effects on the CVD risk profile.

[The testing methods of the medical ultrasonic linear array transducer]

This paper explores the testing methods of the linear array transducer in regard to its integrality, Uniformity and independence.

Endomorphin-1 mediates 2 Hz but not 100 Hz electroacupuncture analgesia in the rat

This work was designed to elucidate the possible involvement of endogenous endomorphin-I (EM1) in analgesia induced by electroacupuncture of low or high frequencies. Taking radiant heat tail flick latency (TFL) as an indication of nociception, rats were subjected to intrathecal (i.t.) injection of 10 microl antiserum against EM1 (EM1-AS) or normal rabbit serum (NRS, as control) and then followed by 2 or 100 Hz electroacupuncture stimulation for 30 min. The analgesia induced by 2 Hz electroacupuncture was attenuated by i.t. injection of EM1-AS at 1:10 and 1:100 but not at 1:1000 dilution. No such suppressive effect was observed for 100 Hz EA analgesia when EM1-AS was injected i.t. at any dilutions. These results indicate that EM1 is involved in 2 Hz but not 100 Hz electroacupuncture analgesia at spinal level.

Effects of stuffer DNA on transgene expression from helper-dependent adenovirus vectors

We have analyzed transgene (lacZ) expression from a first-generation adenovirus (Ad) vector in comparison to helper-dependent (hd) Ads deleted for various portions of the viral coding sequences and generated by using the Cre/loxP helper-dependent system (R. J. Parks et al., Proc. Natl. Acad. Sci. USA 93:13565-13570, 1996). An hd vector deleted for approximately 70% of the Ad genome (AdRP1001) provided levels and durations of transgene expression similar to those of a control first generation Ad vector containing an identical expression cassette. Deletion of all Ad sequences from the hdAd and replacement with a approximately 22-kb fragment of lambda DNA resulted in a decrease in the level and duration of lacZ expression which could not be reversed by the inclusion of a matrix attachment region. However, substitution of the lambda stuffer in the fully deleted hdAd with sequences from the human hypoxanthine-guanine phosphoribosyltransferase gene resulted in significantly improved transgene expression. In vitro assays for cytotoxic T lymphocytes (CTL) directed against putative peptides encoded by the vector backbone showed that, although CTL were generated against the vector containing the lambda DNA, no such CTL were generated against the vector containing the hypoxanthine-guanine phosphoribosyltransferase (HPRT) sequences. Surprisingly, the rate of loss of the HPRT- and lambda-containing vectors from mouse liver was similar, despite the differences in expression kinetics, indicating that the lambda stuffer-directed CTL were inefficient at eliminating the transduced cells. Thus, the nature of the DNA backbone of hdAds can have important effects on the functioning of the vector. Since most fully deleted vectors require "stuffer" DNA as part of the vector backbone to maintain optimum vector size, these observations must be taken into account in the design of hdAd vectors.

Testing for linkage under robust genetic models

Robust genetic models are used to assess linkage between a quantitative trait and genetic variation at a specific locus using allele-sharing data. Little is known about the relative performance of different possible significance tests under these models. Under the robust variance components model approach there are several alternatives: standard Wald and likelihood ratio tests, a quasilikelihood Wald test, and a Monte Carlo test. This paper reports on the relative performance (significance level and power) of the robust sibling pair test and the different alternatives under the robust variance components model. Simulations show that (1) for a fixed sample size of nuclear families, the variance components model approach is more powerful than the robust sibling pair approach; (2) when the number of nuclear families is at least approximately 100 and heritability at the trait locus is moderate to high (>0.20) all tests based on the variance components model are equally effective; (3) when the number of nuclear families is less than approximately 100 or heritability at the trait locus is low (<0. 20), on balance, the Monte Carlo test provides the best power and is the most valid. The different testing procedures are applied to determine which are able to detect the known association between low density lipoprotein cholesterol and the common genotypes at the locus encoding apolipoprotein E. Results from this application show that the robust sibling pair method may be more effective in practice than that indicated by simulations.

Germline mutations in the extracellular domains of the 55 kDa TNF receptor, TNFR1, define a family of dominantly inherited autoinflammatory syndromes

Autosomal dominant periodic fever syndromes are characterized by unexplained episodes of fever and severe localized inflammation. In seven affected families, we found six different missense mutations of the 55 kDa tumor necrosis factor receptor (TNFR1), five of which disrupt conserved extracellular disulfide bonds. Soluble plasma TNFR1 levels in patients were approximately half normal. Leukocytes bearing a C52F mutation showed increased membrane TNFR1 and reduced receptor cleavage following stimulation. We propose that the autoinflammatory phenotype results from impaired downregulation of membrane TNFR1 and diminished shedding of potentially antagonistic soluble receptor. TNFR1-associated periodic syndromes (TRAPS) establish an important class of mutations in TNF receptors. Detailed analysis of one such mutation suggests impaired cytokine receptor clearance as a novel mechanism of disease.

Murine dendritic cells transduced with an adenoviral vector expressing a defined tumor antigen can overcome anti-adenovirus neutralizing immunity and induce effective tumor regression

In this study transduced dendritic cells (DCs) were used to enhance immunogenecity of a specific tumor antigen. Using a polyoma middle T (PyMT) transgenic mammary carcinoma model we found that injections of DCs transduced with an adenoviral (Ad) vector expressing PyMT (DCAd-PymT) led to potent specific anti-tumor immunity. Efficacy was not affected by neutralizing Abs (high or low titers) and naive animals did not produce detectable anti-Ad Abs following two injections of transduced DCs. Repeated injections of transduced DCs significantly improved therapeutic efficacy in mice with established lung metastases. These data emphasize the ability of Ad-infected DCs to: i) minimize anti-Ad Ab production, ii) overcome pre-existing anti-Ad humoral immunity, and iii) improve vaccination efficacy when injected more than once.

Adenoviral vectors expressing lymphotactin and interleukin 2 or lymphotactin and interleukin 12 synergize to facilitate tumor regression in murine breast cancer models

We have previously demonstrated that intratumoral injection with Ad vectors expressing IL-2 or IL-12 can induce regression in a murine breast cancer model. These IL-2- or IL-12-induced antitumor responses were mainly mediated by Ag-specific T cells. Lymphotactin is a novel lymphocyte chemokine that can cause local accumulation of CD4+, CD8+, and NK cells. We hypothesized that addition of lymphotactin may enhance the antitumor immune responses induced by locally produced IL-2 and IL-12 as we have previously shown. To this end we constructed two double-recombinant adenoviral vectors expressing lymphotactin along with either IL-2 (Ad5 Lym/IL-2) or IL-12 (Ad5 Lym/IL-12). Subcutaneous injection of polyoma middle T (PyMT) or Neu (8142) transgenically derived breast adenocarcinoma cells, in the hind flank of FVB/n mice, results in the formation of tumor nodules in 14-21 days. We show that these constructs elicit potent antitumor responses when administered intratumorally. The antitumor responses are long lasting as determined by rechallenge experiments and hence demonstrate a protective immunity. These observations indicate that by augmenting the antitumor response with adenoviral vectors expressing lymphotactin in combination with IL-2 or IL-12 is a novel way to enhance immunotherapeutic approaches.

Adenovector-mediated gene delivery of interleukin-2 in metastatic breast cancer and melanoma: results of a phase 1 clinical trial

We conducted a phase 1 trial of direct injection of an E1, E3-deleted adenovirus encoding interleukin-2 (AdCAIL-2) into subcutaneous deposits of melanoma or breast cancer. Twenty-three patients were injected at seven dose levels (10(7)-10(10) p.f.u). Local inflammation was observed at the site of injection in 60% of patients, but side-effects were otherwise minor. Incomplete local tumor regression occurred at the site of injection in 24% of patients, but no conventional clinical responses were seen. Circulating CD4 and CD8 counts fell significantly 24 h after injection. Post-injection biopsies demonstrated tumor necrosis and lymphocytic infiltration with the predominant tumor-infiltrating cells both CD3- and CD8-positive. Vector-derived sequences were detected in 14 of 18 biopsies examined 7 days after injection and vector-derived hIL-2 mRNA was detected in 80% of 7-day biopsies processed after injection of 10(8) p.f.u. of AdCAIL-2 or higher. While IL-2 was detectable by ELISA in tumor biopsies at 48 h, no protein was detectable in injected tumors after 7 days and no circulating IL-2 was detectable at any time-point. No Ad5E1 sequences were detected either before or after injection indicating absence of replication-competent virus or endogenous E1-like sequence; furthermore, only rare vector shedding was detected. Anti-adenovirus and neutralizing antibody titers were elevated 1 month after injection in all patients. This trial therefore confirms the safety of use of adenoviral vectors for gene delivery in humans and demonstrates successful transgene expression even in the face of pre-existing immunity to adenovirus.

Phenotype, function, and in vivo migration and survival of allogeneic dendritic cell progenitors genetically engineered to express TGF-beta

BACKGROUND

Administration of donor bone marrow (BM)-derived dendritic cell (DC) progenitors (DCp) that are major histocompatibility complex (MHC) class II+ but costimulatory molecule (CD40, CD80, CD86)-deficient can prolong mouse heart allograft survival This is associated with microchimerism and inhibition of antidonor cytotoxic T lymphocyte (CTL) activity. Genetic modification of these donor antigen-presenting cells to express an immunosuppressive molecule(s) may enhance their in vivo survival and potential tolerogenicity.

METHODS

The surface phenotype of B10(H-2b) DCp before and after gene transfer using replication-deficient adenoviral (Ad) vectors was determined by monoclonal antibody (mAb) staining and flow cytometry. Transforming growth factor-beta (TGF-beta) production was quantitated by enzyme-linked immunosorbent assay. Allostimulatory activity of the gene-transduced DCp was ascertained by mixed leukocyte reaction (MLR) and CTL induction. To assess their in vivo migratory activity and survival, the transduced cells were injected subcutaneously into one hind footpad of C3H (H-2k) mice. Tissues (draining popliteal lymph nodes [LN], spleens, and thymi) were removed 1, 2, 7, and 14 days later and stained for donor MHC class II using anti-LA(b) mAb in an immunohistochemical procedure. The mean number of IAb+ cells per unit area was determined.

RESULTS

Transduction with a control Ad vector (Ad-LacZ) at 50 multiplicity of infection slightly increased CD40 and CD86 expression and up-regulated the poor allostimulatory activity of the DCp assessed by MLR and CTL responses. These effects on function were negated in Ad-TGF-beta1-transduced cells. After their injection into mouse footpads, the gene-transduced IAb+ cells were observed in maximal numbers in the popliteal LN at day 1 and in marginal zones and T-dependent areas of spleens (peak at day 7) but were rare in thymi. Transduction with Ad-LacZ reduced the numbers of IAb+ cells identified in both LN and spleens at all time points postinjection, suggesting that the vector alone affected DC life span in allogeneic recipients. TGF-beta1 transgene expression not only fully prevented the reduction in DC induced by Ad transduction alone, but also increased numbers and prolonged the survival of donor cells in the spleen, as shown by a two-to fivefold increase in IAb+ cells at days 2-14 compared with control (Ad-LacZ-transduced) DC.

CONCLUSION

BM-derived DCp can be transduced efficiently to express TGF-beta1 using an Ad vector. They exhibit very poor allostimulatory activity and similar migration characteristics in vivo to unmodified DCp. Survival of TGF-beta gene-transduced DC, however, is enhanced significantly compared with unmodified and (especially) control Ad-LacZ gene-transduced DC. Genetic engineering of donor DC to express the immunosuppressive molecule TGF-beta promotes their survival in allogeneic hosts and may potentiate their previously reported tolerogenicity.

[Clinical application of TMS-MEP in spinal cord injury]

OBJECTIVE

To evaluate transcranial magnetic stimulation motor evoked potential (TMS-MEP) in the diagnosis of spinal cord injury.

METHOD

56 patients with injury of the spinal cord and cauda equina were examined using TMS-MEP and followed up.

RESULT

In 21 patients with complete paralysis, TMS-MEP of bilateral tibialis anterior and gastrocnemius disappeared and paralysis did not recover. Abnormal was noted TMS-MEP and paralysis not recovered in 2 patients with injury of conus medullaris and cauda equina. Incomplete paralysis occurred in 35 patients. TMS-MEPs of more than one muscle in every patient were recorded. Paralysis and TMS-MEPs recovered in different degree in the 33 patients, in which the strength was 0 class and TMS-MEPs were abnormal in 25 target muscles before operation whereas their strength obviously recovered or even normalized after operation except two muscles.

CONCLUSION

TMS-MEP is an effective method for diagnosis and prognosis of spinal cord injury.

Enhanced interleukin-2 gene transfer immunotherapy of breast cancer by coexpression of B7-1 and B7-2

The capability of B7-1 to augment the antitumor activity of some cytokines has been shown primarily for such cytokines as interleukin-12 (IL-12), IL-7, and to a lesser extent IL-2. In this study, we investigate the ability of B7-1 and B7-2 to augment the antitumor activity of IL-2. Considering the affinity of both molecules for CD28 (T cell receptor for B7-1 and B7-2), we postulated that their potential to augment IL-2 antitumor activity would be similar. Two murine transgenic adenocarcinoma models were chosen to investigate the activity of adenoviral vectors constructed to express either B7-1 and IL-2 or B7-2 and IL-2. Before administering the vector intratumorally to tumor-bearing mice, we determined the expression of B7-1, B7-2, MHC I, and MHC II on these tumor cells and demonstrated positive expression of only MHC I. Intratumoral injection of the vector expressing B7-1 and IL-2 resulted in complete regression of all tumors treated. In contrast, the vector expressing B7-2 and IL-2 was significantly less effective at regressing PyMT tumors, whereas both double recombinant vectors demonstrated similar levels of complete regression in the Neu (NDL 8142) model. Regressed mice were all protected for rechallenge in both models and demonstrated antigen-specific cytotoxic T lymphocytes (CTL) in the PyMT model. These findings indicate that the combination of IL-2 with B7-1 or B7-2 significantly enhances the antitumor activity of IL-2.

Genetic linkage analysis using lognormal variance components

Typically genetic studies of continuous traits such as cholesterol levels or blood pressure assume that interindividual variability follows a normal distribution. Here we develop methods to analyze positively skewed data by assuming a lognormal distribution. We develop a variance components approach for identifying such effects from a major gene, residual polygenic factors and nongenetic factors. We compare by a simulation study results from fitting this lognormal model with either applying the log transformation or not transforming the data. We found that the lognormal model provided more precise estimates and more powerful tests than a simple log transformation when analyzing lognormally distributed data. Power varied with sibship size. For the same total number of nonindependent sibpairs, larger sibships were less powerful. However, larger sibships are more economical because they require a smaller sample size to obtain a specified power. To illustrate the application of this lognormal model to real data, we studied evidence for linkage between triglycerides and the lipoprotein lipase gene.

The G protein G alpha12 stimulates Bruton's tyrosine kinase and a rasGAP through a conserved PH/BM domain

Heterotrimeric guanine-nucleotide-binding proteins (G proteins) are signal transducers that relay messages from many receptors on the cell surface to modulate various cellular processes. The direct downstream effectors of G proteins consist of the signalling molecules that are activated by their physical interactions with a G alpha or Gbetagamma subunit. Effectors that interact directly with G alpha12 G proteins have yet to be identified. Here we show that G alpha12 binds directly to, and stimulates the activity of, Bruton's tyrosine kinase (Btk) and a Ras GTPase-activating protein, Gap1m, in vitro and in vivo. G alpha12 interacts with a conserved domain, composed of the pleckstrin-homology domain and the adjacent Btk motif, that is present in both Btk and Gap1m. Our results are, to our knowledge, the first to identify direct effectors for G alpha12 and to show that there is a direct link between heterotrimeric and monomeric G proteins.

Effect of estrogen on vascular smooth muscle cells is dependent upon cellular phenotype

To investigate the growth-regulating action of estrogen on vascular smooth muscle cells (SMC), effects of beta-17-estradiol (beta-E2) on phenotypic modulation and proliferation of rabbit aortic SMC were observed in vitro. At 10(-8)M, beta-E2 significantly slowed the decrease in volume fraction of myofilaments (Vv myo) of freshly dispersed SMCs in primary culture, indicating an inhibitory effect of beta-E2 on spontaneous phenotypic modulation of SMC from a contractile to a synthetic phenotype. Freshly dispersed SMCs treated with beta-E2 also had a relatively longer quiescent phase than control cells before intense proliferation occurred. This was in contrast to SMCs in passage 2 3 (synthetic state), where beta-E2-treated cells replicated significantly faster than untreated cells. beta-E2 also markedly enhanced the serum-induced DNA synthesis of synthetic SMCs in a concentration-dependent manner within physiological range (10(-10)to 10(-8)M). These findings indicate that the growth-regulating effect of estrogen on vascular SMC is dependent on the cell's phenotypic state. It delays the cell cycle re-entry of the contractile SMCs by retarding their phenotypic modulation: however, once cells have modulated to the synthetic phenotype, it promotes their replication.

Identification of a novel point mutation (Leu72Pro) in the NADH-cytochrome b5 reductase gene of a patient with hereditary methaemoglobinaemia type I

Utilizing polymerase chain reaction (PCR) related technology, we investigated the b5R gene of a Chinese patient with hereditary methaemoglobinaemia type I and found a novel missense mutation (CTC-CCC) at codon 72 in exon 3 of the gene. As the mutation generates an Apa I recognition site, homozygosity for the mutation was confirmed by restriction analysis of PCR-amplified fragments from the patient's genomic DNA. We predicted that the residue replacement of Leu with Pro of the mutant enzyme would account for the b5R deficiency in the patient. The results further confirm the genetic polymorphism of b5R gene mutations found in the RCM type I.

OFQ reverses the kappa-opioid receptor-mediated depression of calcium current in rat dorsal root ganglion neurons

Since the characterization of orphanin FQ (OFQ), the endogenous ligand of ORL1 receptor, much work has focused on its physiological functions. OFQ was reported to antagonize the effect of opioid-induced antinociception, although its mechanism remains obscure. In the present study, whole-cell patch clamp recording technique was used to observe if OFQ can reverse the inhibition of calcium current produced by the kappa-opioid agonist U50,488H (U50) in acutely dissociated rat DRG neurons. The concentrations of OFQ and U50 were 50 nM and 10 microM, respectively. Among 49 cells recorded, the calcium channel currents of 37 (75.5%) cells were inhibited by U50, of which 30 (81.1%) cells could be reversed by OFQ. It was interesting to note the similarity between OFQ and the well characterized anti-opioid peptide CCK-8 in that it reversed kappa-opioid receptor agonist induced suppression on calcium channel current, while by itself showed a calcium channel suppressive effect. Thus OFQ may be regarded as another anti-opioid peptide.

Analysis of the Gs/mitogen-activated protein kinase pathway in mutant S49 cells

Heterotrimeric G protein-coupled receptors can activate the mitogen-activated protein kinase (MAPK) cascade. Recent studies using pharmacological inhibitors or dominant-negative mutants of signaling molecules have advanced our understanding of the pathways from G protein-coupled receptors to MAPK. However, molecular genetic analysis of these pathways is inadequate in mammalian cells. Here, using the well characterized Gsalpha- and protein kinase A-deficient S49 mouse lymphoma cells, we provide the molecular genetic evidence that Gsalpha is responsible for transducing the beta-adrenergic receptor signal to MAPK in a protein kinase A-dependent pathway involving Rap1 and Raf (but not Ras) molecules.

[Anti-tumor effect of cytotoxic T lymphocytes induced by soluble antigen of ovarian carcinoma and anti-CD3 monoclonal antibody on ovarian carcinoma]

OBJECTIVE

To evaluate the therapeutic effect of the new method--adoptive cell immunotherapy on ovarian carcinoma.

METHODS

Tumor soluble antigen (TSA) was extracted from cells of ovarian carcinoma (COC1 and COC2n). To generate cytotoxic T lymphocytes (CTL), peripheral blood mononuclear cells (PBMC) collected from healthy persons were induced by TSA and anti-CD3 monoclonal antibody (CD3-McAb). The antitumor effect of CTL on COC1 cells in vitro was compared with LAK and CD3-AK, whereas the growth inhibitory effect of CTL on COC2n transplantation tumors in nude mice was compared with CD3-AK.

RESULTS

The cytotoxicity of CTL, CD3-AK and LAK was 79.4%, 52.1% and 51.7% respectively (P < 0.01). Mean volume of tumor in nude mice on the 9th day after ovarian carcinoma cells transplanted was 44.4 +/- 24.2 mm3 in CTL group, 118.8 +/- 40.0 mm3 in CD3-AK group and 443.0 +/- 158.7 mm3 in control (no treatment) (P < 0.01), whereas mean duration of survival was 28.5 days, 25.5 days and 17 days respectively (P < 0.01).

CONCLUSION

The results indicated that CTL exhibited higher cytotoxic effect in vitro and greater inhibitory effect on tumor growth resulting in longer survival in vivo. It suggested that the adoptive cell immunotherapy might provide a new idea for treatment of ovarian carcinoma.

Linkage of familial Hibernian fever to chromosome 12p13

Autosomal dominant periodic fevers are characterized by intermittent febrile attacks of unknown etiology and by recurrent abdominal pains. The biochemical and molecular bases of all autosomal dominant periodic fevers are unknown, and only familial Hibernian fever (FHF) has been described as a distinct clinical entity. FHF has been reported in three families-the original Irish-Scottish family and two Irish families with similar clinical features. We have undertaken a genomewide search in these families and report significant multipoint LOD scores between the disease and markers on chromosome 12p13. Cumulative multipoint linkage analyses indicate that an FHF gene is likely to be located in an 8-cM interval between D12S77 and D12S356, with a maximum LOD score (Z max) of 3.79. The two-point Z max was 3.11, for D12S77. There was no evidence of genetic heterogeneity in these three families; it is proposed that these markers should be tested in other families, of different background, that have autosomal dominant periodic fever, as a prelude to identification of the FHF-susceptibility gene.

Retinoic acid inhibits induction of c-Jun protein by ultraviolet radiation that occurs subsequent to activation of mitogen-activated protein kinase pathways in human skin in vivo

Human skin is exposed daily to solar ultraviolet (UV) radiation. UV induces the matrix metalloproteinases collagenase, 92-kD gelatinase, and stromelysin, which degrade skin connective tissue and may contribute to premature skin aging (photoaging). Pretreatment of skin with all-trans retinoic acid (tRA) inhibits UV induction of matrix metalloproteinases. We investigated upstream signal transduction pathways and the mechanism of tRA inhibition of UV induction of matrix metalloproteinases in human skin in vivo. Exposure of human skin in vivo to low doses of UV activated EGF receptors, the GTP-binding regulatory protein p21Ras, and stimulated mitogen-activated protein (MAP) kinases, extracellular signal-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK), and p38. Both JNK and p38 phosphorylated, and thereby activated transcription factors c-Jun and activating transcription factor 2 (ATF-2), which bound to the c-Jun promoter and upregulated c-Jun gene expression. Elevated c-Jun, in association with constitutively expressed c-Fos, formed increased levels of transcription factor activator protein (AP) 1, which is required for transcription of matrix metalloproteinases. Pretreatment of human skin with tRA inhibited UV induction of c-Jun protein and, consequently, AP-1. c-Jun protein inhibition occurred via a posttranscriptional mechanism, since tRA did not inhibit UV induction of c-Jun mRNA. These data demonstrate, for the first time, activation of MAP kinase pathways in humans in vivo, and reveal a novel posttranscriptional mechanism by which tRA antagonizes UV activation of AP-1 by inhibiting c-Jun protein induction. Inhibition of c-Jun induction likely contributes to the previously reported prevention by tRA of UV induction of AP-1-regulated matrix-degrading metalloproteinases in human skin.

Case-control study of the D2 dopamine receptor gene and smoking status in lung cancer patients

BACKGROUND

Interindividual differences in the structure and expression of the dopamine receptor genes affect dopamine availability and may be the genetic basis for variation in vulnerability to tobacco smoking. In this study, prevalences of polymorphisms in the TaqIA allele (A1 and A2) and the TaqIB allele (B1 and B2) of the D2 dopamine receptor gene in 157 lung cancer case patients and 126 control subjects were determined to assess whether individuals homozygous or heterozygous for the less common A1 and B1 alleles are more vulnerable to nicotine addiction.

METHODS

Case and control subjects were accrued from an ongoing epidemiologic study. Blood samples were collected from them and subjected to molecular genetic analyses. Subjects were interviewed to obtain relevant information. Current and former smokers were administered a questionnaire to quantify their addiction to nicotine.

RESULTS

The combined B1B2 genotypes appeared to be more prevalent in ever smokers than in never smokers among case patients (30.3% versus 13.3%; two-sided P = .233) and among control subjects (30.9% and 0%; two-sided P = .02); statistically significant differences were not observed among those with A1 genotypes. Statistically significant correlations between the presence of the A1 and B1 alleles were observed (r = .73 for case subjects and r = .76 for control subjects; two-sided P<.001). Individuals with rarer genotypes reported having been substantially younger at the time of smoking initiation (statistically significant for both A1 and B1) and having attempted to quit smoking fewer times (statistically significant for only A1).

CONCLUSION

Variant alleles of the D2 dopamine receptor gene may play a role in determining nicotine addiction, although the associations between the at-risk genotypes and measures of nicotine addiction were not entirely consistent.

A double recombinant adenovirus expressing the costimulatory molecule B7-1 (murine) and human IL-2 induces complete tumor regression in a murine breast adenocarcinoma model

Tumors that express tumor-specific antigens can maintain growth in an immunocompetent organism. Current hypotheses tend toward T cell anergy as a key component for the inhibition of immunoreactivity against such tumors. Anergy is thought to occur from hyperactive stimulation of the TCR in the absence of costimulation (costimulation leads to proliferation via IL-2 production). Subcutaneous injection of transgenic polyoma middle T transformed breast adenocarcinoma tumor cells (PyMT) in the hind flank of FVB/n mice results in the formation of tumor nodules at this site. We determined the MHC class I and class II, B7-1, and B7-2 expression in the tumor cells by flow cytometry and showed positive staining for only MHC class I. We show that a single E1-deleted adenovirus constructed to express both the costimulatory molecule B7-1 (murine) and human IL-2 genes (Ad5E1 mB7-1/human IL-2) elicits a very potent antitumor response when administered intratumorally. Ad5E1 mB7-1/human IL-2 induced rapid and complete regression (100%) of all tumors compared with Ad5 E1 mB7-1 (38%), Ad CAIL-2 (42%), and Ad5E1 dl70-3 (control vector) (0%). All mice that exhibited complete tumor regression were fully protected in tumor cell challenge experiments. The systemic immunity generated by intratumoral administration of the Ad vectors was associated with a strong anti-PyMT CTL response. These observations indicate that augmenting the immunogenicity of the tumor with coincident expression of B7-1 in combination with IL-2 may prove beneficial in direct tumor immunotherapy.

Cytochrome P450 2E1 DraI polymorphisms in lung cancer in minority populations

Cytochrome P4502E1 (CYP2E1) is involved in the metabolic activation of carcinogenic N-nitrosamines. This study was performed to examine whether CYP2E1 DraI polymorphisms in intron 6 are related to susceptibility to lung cancer and are associated with carcinogenetic exposure. We therefore genotyped CYP2E1 by PCR amplification of peripheral WBC DNA from 126 patients with previously untreated lung cancer (85 African Americans and 41 Mexican Americans) and 193 controls (104 African Americans and 89 Mexican Americans). Mutagen sensitivity was measured with an in vitro assay quantitating bleomycin-induced chromatid breaks in peripheral blood lymphocyte cultures. The CYP2E1 DraI DD genotype was found in 86.5% of all cases and in 74.6% of all controls (P = 0.03), in 78.1% of 41 Mexican-American cases and in 69.6% of their controls (P = 0.70), and in 90.6% of African American cases and in 78.8% of their controls (P = 0.05). The DD genotype was found to be associated with a significantly higher risk of lung cancer overall with an odds ratio (OR) of 2.4 [95% confidence interval (CI), 1.1-5.3]. This risk was significantly elevated for men and for those who had ever smoked [ORs of 3.4 (95% CI, 1.3-8.7) and 2.6 (95% CI, 1.1-6.0), respectively], but not for women and nonsmokers [ORs of 0.7 (95% CI, 0.1-3.8) and 0.9 (95% CI, 0.1-10.6), respectively]. Stratified analysis showed an interaction that seemed greater than multiplicative between cigarette smoking and the CYP2E1 DraI DD genotype. The ORs for the CYP2E1 DraI DD genotype, cigarette smoking, and both risk factors combined were 1.5, 8.5, and 22.7, respectively. The CYP2E1 DraI polymorphism and the CYP2E1 PstI polymorphism in the upstream flanking regions were significantly associated in Mexican Americans but not in African Americans. We therefore conclude that the CYP2E1 DraI polymorphism seems to be associated with lung carcinogenesis. However, a larger study is warranted to evaluate the interactions among CYP2E1 DraI DD genotype, mutagen sensitivity, and cigarette smoking.

Optimal seat suspension design based on minimum "simulated subjective response"

This work addresses a method for improving vertical whole body vibration isolation through optimal seat suspension design. The primary thrusts of this investigation are: (1) the development of a simple model that captures the essential dynamics of a seated human exposed to vertical vibration, (2) the selection and evaluation of several standards for assessing human sensitivity to vertical vibration, and (3) the determination of the seat suspension parameters that minimize these standards to yield optimal vibration isolation. Results show that the optimal seat and cushion damping coefficients depend very much on the selection of the vibration sensitivity standard and on the lower bound of the stiffnesses used in the constrained optimization procedure. In all cases, however, the optimal seat damping obtained here is significantly larger (by than a factor of 10) than that obtained using existing seat suspension design methods or from previous optimal suspension studies. This research also indicates that the existing means of assessing vibration in suspension design (ISO 7096) requires modification.

Genetic Transformation of Wheat Mediated by Agrobacterium tumefaciens

A rapid Agrobacterium tumefaciens-mediated transformation system for wheat was developed using freshly isolated immature embryos, precultured immature embryos, and embryogenic calli as explants. The explants were inoculated with a disarmed A. tumefaciens strain C58 (ABI) harboring the binary vector pMON18365 containing the [beta]-glucuronidase gene with an intron, and a selectable marker, the neomycin phosphotransferase II gene. Various factors were found to influence the transfer-DNA delivery efficiency, such as explant tissue and surfactants present in the inoculation medium. The inoculated immature embryos or embryogenic calli were selected on G418-containing media. Transgenic plants were regenerated from all three types of explants. The total time required from inoculation to the establishment of plants in soil was 2.5 to 3 months. So far, more than 100 transgenic events have been produced. Almost all transformants were morphologically normal. Stable integration, expression, and inheritance of the transgenes were confirmed by molecular and genetic analysis. One to five copies of the transgene were integrated into the wheat genome without rearrangement. Approximately 35% of the transgenic plants received a single copy of the transgenes based on Southern analysis of 26 events. Transgenes in T1 progeny segregated in a Mendelian fashion in most of the transgenic plants.

Estimating the strength of genetic effects: a comparison of maximum likelihood and transmission disequilibrium methods in the study of ankylosing spondylitis

Here we compare several methods for evaluating associations in the analysis of family data. We applied the transmission disequilibrium test (TDT), and logistic regression, familial aggregation, and segregation analyses for the study of Ankylosing Spondylitis. All methods detected effects from B27 upon susceptibility for Ankylosing Spondylitis. However, the TDT was unable to detect effects from B40 and also could not include sex as a covariate during the analysis. Conditioning or not conditioning the data for the ascertainment event led to little difference in the estimated covariate effects, although the genetic model for residual effects not due to the covariates did change. Results from these studies provide further characterization of the relationship between HLA B27, B40, and sex upon risk for developing Ankylosing Spondylitis. We also identified potential effects from further genetic susceptibility.

[Studies on programmed cell death induced by amsacrine and expression of bcl-2 in leukemia cell lines]

OBJECTIVE

To study programmed cell death (PCD) in two human acute myelocytic leukemia cell lines in different differentiated phases, NB4(AML3) and HL-60(AML2).

METHODS

PCD cells were detected microscopically, DNA electrophoretically and flow cytometrically. Expression of bcl-2 gene was examined by immunohistochemistry staining.

RESULTS

Exposed to 1-20 micrograms/ml m-AMSA for 6-12 h, morphological changes in NB4 cells were more evident than in HL-60 cells. Internucleosomal fragmentation(DNA ladders) was more marked in NB4 than in HL-60 cells. Flow cytometric analysis indicated that the number of PCD cells in NB4 cells was more than that in HL-60 cells. HL-60 cells had significantly higher mean bcl-2 level than NB4 cells.

CONCLUSION

The high bcl-2 level in HL-60 cells may be related to their comparatively low sensitivity to m-AMSA-induced PCD.

Dendritic cells transduced with an adenoviral vector encoding a model tumor-associated antigen for tumor vaccination

Evaluation of the potential role of dendritic cells (DCs) as adjuvants for tumor vaccination has focused primarily on techniques that load DCs with peptide tumor antigens. Our aim has been to optimize the induction of antitumor immunity by enhancing the ability of DCs to present tumor-associated antigens endogenously to the afferent lymphatic system in the appropriate major histocompatibility complex (MHC)-restricted context. We have used replication-defective adenovirus vectors (Ads) to transduce DCs with various genes, including tumor antigen genes. We found that 90% of murine bone marrow derived-DCs could be infected with an Ad vector expressing the beta-galactosidase gene and still retain their physiologic and phenotypic characteristics. Furthermore, we demonstrated that transgene expression was detectable in the spleen for at least 3 days following intravenous injection of Ad-transduced DCs. Using a polyoma middle T (PymT) transgenic murine mammary carcinoma model, we have shown that a single injection of 10(5)-4 x 10(6) DCs transduced with an Ad vector expressing PymT provided complete and specific protection against tumor cell challenge in 100% of vaccinated animals. Immunization against the PymT tumor by injection with the PymT expressing Ad vector alone resulted in varying degrees of effectiveness, was highly dependent upon the route of administration, and led to significant hepatic toxicity that was not seen in mice immunized with DC transduced with the Ad vector. Our results suggest that: (i) DCs can be very efficiently modified by ex vivo Ad transduction to express tumor-specific antigens, (ii) such modified DCs appear nontoxic and stimulate a potent antitumor response.

Genetic evidence for a tyrosine kinase cascade preceding the mitogen-activated protein kinase cascade in vertebrate G protein signaling

The signal transduction pathway from heterotrimeric G proteins to the mitogen-activated protein kinase (MAPK) cascade is best understood in the yeast mating pheromone response, in which a serine/threonine protein kinase (STE20) serves as the critical linking component. Little is known in metazoans on how G proteins and the MAPK cascade are coupled. Here we provide genetic and biochemical evidence that a tyrosine kinase cascade bridges G proteins and the MAPK pathway in vertebrate cells. Targeted deletion of tyrosine kinase Csk in avian B lymphoma cells blocks the stimulation of MAPK by Gq-, but not Gi-, coupled receptors. In cells deficient in Bruton's tyrosine kinase (Btk), Gi-coupled receptors failed to activate MAPK, while Gq-coupled receptor-mediated stimulation is unaffected. Taken together with our previous data on tyrosine kinases Lyn and Syk, the Gq-coupled pathway requires tyrosine kinases Csk, Lyn, and Syk, while the Gi-coupled pathway requires tyrosine kinases Btk and Syk to feed into the MAPK cascade in these cells. The central role of Syk is further strengthened by data showing that Syk can bind to purified Lyn, Csk, or Btk.

A transcript map encompassing the multiple endocrine neoplasia type-1 (MEN1) locus on chromosome 11q13

A transcription map of a 1200-kb region encompassing the MEN1 locus was constructed by direct cDNA selection and mapping ESTs. A total of 29 genes were mapped. Ten transcripts were identified by cDNA selection of a focused 300-kb genomic region telomeric to the MEN1 consensus region. Since many of the sequences cloned by cDNA selection also identified ESTs from the region, 19 additional RH-mapped ESTs were mapped to the entire contig region by PCR amplification of genomic clones. Nine known genes, 2 putative human homologues to mouse genes, and 18 novel transcripts map to the region. Transcripts that map to the MEN1 interval PYGM-D11S449 include SGC35223, IB1256, AA147620, ZFM1, FAU, and CAPN1. The latter 3 known genes have already been excluded as candidate MEN1 genes. The 2 putative human homologues of mouse genes Ltbp2 and Spa-1 may be candidate tumor suppressor genes, but they map telomeric to D11S449. Although both of these genes map outside the MEN1 consensus region they may play a role in sporadic endocrine tumors independent of the MEN1 gene or in other tumors, such as breast cancer, that have loss of heterozygosity within this region.

[A study on histogenesis of gastrointestinal stromal tumors]

OBJECTIVE

The purpose of this study was to consider the histogenesis of gastrointestinal stromal tumors (GIST).

METHOD

36 cases of GIST were studied by light microscopy, histochemical and immunohistochemical techniques.

RESULTS

In 15 cases of small intestine spindle cell tumors, various sized eosinophilic globules were observed between the tumor cells and were designated as skeinoid fibers, which stained blue with Masson's trichrome and strongly PAS-positive. The positive rate by immunohistochemical methods for S-100 protein and desmin were 44.44% and 8.33% respectively. The immunoexpression of tumor cells was unrelated to their differentiation.

CONCLUSION

Complex immunophenotypes of GIST suggest primitive mesenchymal origin, and small intestine stromal tumors (SIST) are mostly neurogenic which may have been derived from neurilemmal cells or autonomous nerve tissue of the small intestine.

Genome analysis on linkage group VI of Neurospora crassa

Two chromosome walks covering 420 and 110 kb on the left arm of linkage group VI (LGVIL) of Neurospora crassa were purscrooued with the goal of cloning carotenogenic loci. Complementation analysis with clones isolated in the 420-kb walk allowed identification of the yellow-1 (ylo-1) gene which is essential for Neurospora carotenogenesis. We have physically located a second gene, unknown-13 (un-13), between the cross-pathway control-1, (cpc-1) and ylo-1 loci. Cloning of a second potential carotenogenic locus, vivid (vvd), from our walks was attempted using screening of Northern blots with radiolabeled DNA fragments from walk clones to identify gene transcripts. The radiolabeled DNA fragments were used to clone complementary DNA isolates representing an additional four genes in the two walks.

Intramarrow cytokine gene transfer by adenoviral vectors in dogs

Daily systemic administration of hematopoietic growth factors can be associated with dose-limiting systemic side effects. To overcome this, we have investigated hematopoietic cytokine gene transfer to the marrow cavity of dogs by direct intramarrow injection of adenoviral vectors. In marrow culture, replication-deficient (E1-deleted) adenoviral vectors were able to transduce marrow stromal cells, demonstrating 30-fold greater expression than from other marrow cell types. High-level (ng/ml) cytokine production from transduced stromal cells persisted for 14 days in culture. Because adenovectors could efficiently transduce marrow stromal cells in culture, we investigated if stromal cells could also be transduced in vivo following direct intramarrow vector injection. Adenovectors with genes for interleukin 6 (IL-6) and Lac Z (beta-galactosidase) were injected directly into the marrow cavity of dogs resulting in protein expression localized to within the treated marrow. To evaluate this approach further in dogs, we constructed a vector expressing biologically active canine granulocyte-macrophage colony stimulating factor (GM-CSF). 293 cells infected with ADGM-CSF demonstrated prevalent GM-CSF mRNA by Northern blot and 135 +/- 30 ng/ml of protein as measured by enzyme-linked immunosorbent assay (ELISA). In vitro bioactivity of protein expressed was confirmed by canine GM colony-forming assay (CFU-GM). In vivo high-level protein production was noted in supernatants of marrow aspirates 72 hr following direct intramarrow administration of ADGM-CSF (baseline mean +/- SEM, 27 +/- 22 ng/ml, 72-hr sample 921 +/- 461 ng/ml). A localized myeloid expansion of marrow and significant peripheral leukocytosis (neutrophilia) were noted in all ADGM-CSF-treated dogs. Peripheral blood changes lasted for up to 3 weeks in dogs following single intramarrow injection. Thus, adenoviral cytokine expression from the marrow of a single large bone (ilium) led to compartmentalized expression of growth factor and an increase of hematopoiesis sufficient to cause peripheral blood changes in a large animal model.

A permutation test for the robust sib-pair linkage method

The robust sib-pair method introduced by Haseman & Elston (1972) is one of the most widely circulated allele-sharing methods for linkage analysis. The procedure evaluates linkage by significance testing of a regression coefficient and, hence, a standard t-test has traditionally been applied despite known violations of the statistical assumptions underlying the test. We present a permutation based reference distribution for the estimate of the regression coefficient that is motivated by genetic principles rather than by standard regression testing procedures. The permutation test approximates Mendelian co-segregation under the null hypothesis of no linkage, making it a very natural approach. Theory and simulations show that the conventional t-test approximates the permutation test quite well, even when dependent sib pairs are used for analysis. These results thus indirectly address concerns over the t-test. To illustrate the permutation test using real data we applied the procedure to two lipoprotein systems that have been well characterized.

[Method of mRNA differential display and its application in life science]

The changes of mRNA expression level control cell function. Many factors such as individual development, cell proliferation and differentiation, and even apoptosis, physiological stimuli, and drug treatment will change the level of gene expression. Comparisons of gene expression in different cell types provide the underlying information for analyzing the molecular and cellular mechanisms of the physiological processes. A method of mRNA differential display is developed recently, providing a powerful and useful tool, which can efficiently and rapidly isolate the genes that display a difference in transcription. These genes may play important role in cell function.

[Environmental pollution, human exposure and its health effect of sodium pentachlorophenate in schistosomiasis prevalent area]

Sodium pentachlorophenate (Na-PCP) has been used in China for years as an molluscacide to kill oncomelania, which is an intermediate host of Schistosome. To evaluate the effects of its long-term successive usage on environment, human exposure and health, studies were carried out in Sichuan, Jiangxi, Jiangsu and Fujian provinces, with a time gap of more than one month between sample collection and last spray of Na-PCP. Results indicated that PCP contents in surface water, soil, sediment, animals and plants were significantly higher in studied areas than in control areas. The daily intake and the content in urine of PCP were also sigificantify higher in studied areas. But, there was no difference on physical and biochemical examinations except that a 22%-28% decrease of blood cholinesterase activity was found in studied areas. The health effect of impurities in Na-PCP, dioxins and furans, was assessed and discussed.

[Renin-angiotension system--stress hormone response system]

Angiotensin II (A II) was significantly increased in both acutely and chronically stressed animals as found in brain, heart, blood vessels and adrenal glands. After running a race, the plasma A II contents of sportsmen similar to cortisol increased markedly too. In the chronical stress-hypertensive animals, the contents of circulating A II and tissue A II were increased quite lastingly. It was also found that the high concentration of A II may stimulate the adrenal gland secreting glucosteroid, and increase of tissue A II may be faciliated by the activation of beta adrenergic receptors. On basis of the above finding, we tend to assume that A II is a stress hormone and the renin angiotension system (RAS) is a stress hormone responses system. Morever there exists a close relation between RAS and two classic stress hormone response systems, i.e. the hypothalamus-pituitary-adrenal cortex system and the sympathetic-adrenal medulla system.

An improved green fluorescent protein gene as a vital marker in plants

A synthetic green fluorescent protein (GFP) gene (pgfp) was constructed to improve GFP expression in plants. Corn and tobacco protoplast transient assays showed that pgfp gave about 20-fold brighter fluorescence than the wild-type gene (gfp). Replacement of the serine at position 65 with a threonine (S65Tpgfp) or a cysteine (S65Cpgfp) yielded 100- to 120-fold brighter fluorescence than wild-type gfp upon excitation with 490-nm light. Incorporation of a plant intron into the coding region yielded an additional 1.4-fold improvement, for a cumulative improvement of about 150-fold in fluorescence at 490-nm excitation. Various versions of pgfp were also stably introduced into corn, wheat, tobacco, and Arabidopsis plants. Bright-green fluorescence was observed with a fluorescence microscope in virtually all examined tissues of transgenic monocots and dicots. In the case of Arabidopsis, expression of the pgfp gene under the enhanced 355 promoter of the cauliflower mosaic virus produced green fluorescence that was readily detectable by eye using a hand-held, long-wave ultraviolet lamp and/or a black-light source.

Adenoviral gene transfer of macrophage inflammatory protein-2 in rat lung

Replication-defective adenoviral vectors are capable of localized transfer and expression of incorporated gene product in lung tissue. We have constructed an adenoviral vector that expresses rat macrophage inflammatory protein (MIP)-2, a C-X-C chemokine specifically chemotactic for neutrophils, Supernatants from 293 cells, infected with the adenoviral MIP-2 (ADMIP-2) construct, showed potent chemotactic activity and the ability of the ADMIP-2 vector to transcribe and make functional protein was confirmed. In vivo analysis of bronchoalveolar lavage fluid from rats after intratracheal instillation of ADMIP-2 (10(9) plaque-forming units) showed a 10-fold increase in the absolute number of neutrophils in bronchoalveolar lavage fluid as opposed to rats treated with an equal titer of an E1-disabled control virus expressing firefly luciferase (ADCA-18). Neutrophils constituted 65% of total BAL cells with alveolar macrophages being the other major cell type recovered. Rat MIP-2 protein was increased (nanograms per milliliter) in bronchoalveolar lavage fluid over a period of 7 days in ADMIP-2-treated animals. MIP-2 mRNA was demonstrated by Northern blot analysis in lung tissue, and histological analysis confirmed the presence of massive localized tissue neutrophilia. Evidence of chronic tissue injury and repair (ie, fibrosis) was not detected up to 2 weeks after the neutrophil infiltrate had resolved, subsequent to decreased chemokine presence. Adenoviral gene transfer proved an effective tool for the assessment of lung tissue expression of this chemokine in vivo and is useful in developing rodent models of tissue neutrophilia.

[Research progress on the glia cell line-derived neurotrophic factor]

Glia cell line-derived neurotrophic factor (GDNF) is a novel type of neurotrophic factor cloned in 1993. Recent research revealed that it may have potential application in the treatment of Parkinson's disease and motor neuron diseases. This short review summarized the character of the protein, gene structure, tissue distribution, and its physiological functions and pathological implications.

Purification and identification of ABA-binding proteins and antibody preparation

Maize root membranes were extracted and the solubilized proteins were affinity-purified using an ABA-BSA-Sepharose 4B matrix. The retained proteins were eluted with 4M urea or 10(-4)M ABA. ABA could elute the binding proteins but other phytohormones, such as IAA or GA3, could not. ABA binding activity was detected in ABA- and urea-elute fractions using competitive ELISA block tests and [3H]ABA binding assays. Scatchard analysis showed an apparent K(d) of 4.8 nM for the ABA binding activity of the protein. When ABA or urea eluate was loaded on a concanavalin-A-Sepharose column, the fraction eluted with 0.2 M methyl alpha-mannopyranoside still showed ABA binding activity, suggesting that ABA binding proteins are glycoproteins. Polyclonal antibodies against ABA binding proteins were raised using as immunogen ABA or urea eluate from the ABA-BSA-Sepharose column. The resulting antibodies not only recognized 56 kDa binding proteins but also blocked the binding of ABA to an ABA-specific antibody, indicating properties similar to anti-idiotypic antibodies. The purified antibodies will be suitable to purify and characterize putative ABA receptors.

[Loss of heterozygosity involving DCC gene in human colorectal cancers is correlated with the metastatic potential]

DCC gene located at chromosome 18q21.3 is an important tumor-supressor gene associated with tumorigenesis and progression, especially in colorectal carcinomas. Adopting Southern blot technique and RFLP analysis, 33 primary Chinese colorectal cancer patients were examined for loss of heterozygosity (LOH) of DCC gene. Among 16 informative cases, 6 (38%) showed allelic deletion. 18q LOH was correlated with lymph node and hepatic metastases (P < 0.05). The results indicate that application of molecular genetics is of value in ascertaining the metastatic potential of colorectal carcinomas.

Tyrosine kinases in activation of the MAP kinase cascade by G-protein-coupled receptors

The mitogen-activated protein kinase (MAPK) signalling cascade is a prominent cellular pathway used by many growth factors, hormones and neurotransmitters to regulate physiological responses. Although activation of the MAPK pathway by receptors with tyrosine kinase activity is well defined, the mechanism used by heterotrimeric G-protein-coupled receptors to activate this pathway is less clear. Here we show that in cells deficient in the Src-related tyrosine kinase Lyn, stimulation of MAPK kinase and MARPK by Gq-coupled m1 muscarinic acetylcholine receptors (mAChR) is blocked, whereas Gi-coupled m2 mAChR-mediated stimulation is unaffected. In cells deficient in the tyrosine kinase Syk, both m1 and m2 mAChRs failed to stimulate MAPK kinase and MAPK. This result indicates that Syk is essential for the Gi-coupled pathway and that Lyn and Syk are necessary for the Gq-coupled pathway.

Factors accounting for different responses of pulmonary and cerebral vessels to hypoxia

The roles of sympathicus, sensory neuropeptides (SNP), cyclooxygenase metabolites (COX-M), lipoxygenase metabolites (LOX-M), endothelium derived relaxing factor (EDRF), reactive oxygen (ROS) and potassium channels (PC) in the hypoxic pulmonary vasoconstriction (HPV) and hypoxic cerebral vasodilation (HCVD) were investigated in intact rats, rabbits and dogs. The results showed that during hypoxia, the excitation of sympathicus caused a constriction of both pulmonary and cerebral vessels, while SNP, EDRF and the opening of voltage sensitive PC caused the dilation of both of them; LOX-M mediated HPV and HCVD, COX-M might serve as their modulators; the blockade of ATP sensitive PC induced by hypoxia mediated HPV, but had no effect on HCVD; the reduction of O2-. in the lung might potentiate HPV, however, O2-. remained unchanged in brain during hypoxia. It is suggested that the alterations of LOX-M, ROS and the ATP sensitive PC are the factors accounting for the difference in the response of pulmonary and cerebral vessels to hypoxia.