Combined nasal administration of encephalitogenic myelin basic protein peptide 68-86 and IL-10 suppressed incipient experimental allergic encephalomyelitis in Lewis rats

Mucosal administration of low doses of myelin basic protein (MBP) peptide 68-86 (MBP 68-86) or anti-inflammatory cytokine IL-10 effectively prevented experimental allergic encephalomyelitis (EAE), but failed to suppress the disease if given after 7 days postimmunization (p.i.), i.e., after T cell priming had occurred. We anticipated that combined administration of autoantigen and IL-10 can treat incipient EAE. Lewis rats with EAE actively induced with MBP 68-86 and complete Freund's adjuvant received 120 microg MBP 68-86 + 200 ng IL-10 per rat per day from day 7 p.i. and for 5 consecutive days. These rats showed later onset, lower clinical scores, less body weight loss, and shorter duration of EAE than rats receiving MBP 68-86 or IL-10 only or PBS. EAE amelioration was associated with decreased infiltration of ED1(+) macrophages and CD4(+) T cells within the central nervous system and with decreased proliferative responses of lymph node cells, indicating that combined administration of MBP 68-86 and IL-10 induced immune hyporesponsiveness. IFN-gamma secretion as well as IFN-gamma, TNF-alpha, IL-4, and IL-10 mRNA expression by lymph node MNC was down-regulated in the treated rats. Immune hyporesponsiveness, rather than immune deviation or regulatory mechanisms, seems to be responsible for the protection of EAE after autoantigen + IL-10 administration by the nasal route.

[Effects of -30 degrees head down tilt on lung function]

OBJECTIVE

To investigate the effects of short-term simulated weightlessness on lung function in healthy males.

METHOD

-30 degrees head down tilt for 45 min was used to simulate short-period weightlessness. Lung function of 12 healthy males, aged 18-21, were studied with plethysmography during seating, supine and head down tilt positions. At the same time, blood flow in pulmonary artery and function of right ventricle were measured with Doppler Echo-Cardiography. Comparative analysis was done.

RESULT

As body position changed from seating or supine into head down tilt, FVC, FEV1, FEV1%, MVV, VA and IVC decreased. The change of MVV was the most prominent (P < 0.000). As the position changed, pulmonary diffusion increased dramatically (DL(CO) P<0.001, K(CO) P<0.000).

CONCLUSION

HDT may lead to a decrease of pulmonary ventilation and lung capacity. The increased pulmonary diffusion might be related to uniform distribution of pulmonary blood flow and increased effective pulmonary vascular bed.

Suppression of ongoing experimental allergic encephalomyelitis (EAE) in Lewis rats: synergistic effects of myelin basic protein (MBP) peptide 68-86 and IL-4

Mucosal myelin autoantigen administration effectively prevented EAE, but mostly failed to treat ongoing EAE. Patients with multiple sclerosis (MS), for which EAE is considered an animal model, did not benefit from oral treatment with bovine myelin. We anticipated that autoantigen, administered together with a cytokine that counteracts Th1 cell responses, might ameliorate Th1-driven autoimmune disease, and that nasal administration might considerably reduce the amounts of antigen + cytokine needed for treatment purposes. Lewis rats with EAE actively induced with myelin basic protein peptide (MBP 68-86) and Freund's complete adjuvant (FCA), received from day 7 post-immunization, i.e. after T cell priming had occurred, 120 microg MBP 68-86 + 100 ng IL-4 per rat per day for 5 consecutive days. These rats showed later onset, lower clinical scores, less body weight loss and shorter EAE duration compared with rats receiving MBP 68-86 or IL-4 only, or PBS. EAE amelioration was associated with decreased infiltration of ED1+ macrophages and CD4+ T cells within the central nervous system, and with decreased interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) and enhanced IL-4, IL-10 and transforming growth factor-beta (TGF-beta) responses by lymph node cells. Simultaneous administration of encephalitogenic peptide + IL-4 by the nasal route thus suppressed ongoing EAE and induced IL-4, IL-10 and TGF-beta-related regulatory elements.

[The preoperative application of selective catheterization and embolism of the external carotid artery in treating tumors with enriched blood supply in the base of skull]

OBJECTIVE

Embolizing the feeding vessels of the tumors with enriched blood supply in the base of skull in order to reduce the bleeding during operation.

METHOD

Under digital subtraction angiographic control, superselectively catheterizing the external carotid artery, thus occluding the terminal branches of the feeding arteries of the tumor with particles of liquidized gelfoam.

RESULT

Nine cases studied showed that the angiography of the feeding vessels of the tumor disappeared relatively. The bleeding decreased significantly during operation. The postoperative pathological findings showed that the entity of the tumor was congested with gelfoam.

CONCLUSION

After figuring out the blood supply of the tumor, superselective catheterization of the external carotid artery followed by occlusion of the feeding vessels can reduce the size of the tumor and diminish the bleeding during operation, thus can improve the safety of the operation. It should be one of the crucial preoperation measures.

Chemokine gene adjuvants can modulate immune responses induced by DNA vaccines

Nucleic acid immunization has been shown to induce both antigen-specific cellular and humoral immune responses in vivo. Moreover, immune responses induced by DNA immunization can be enhanced by the use of molecular adjuvants. For example, coadministration of costimulatory molecules (CD80 and CD86), proinflammatory cytokines (interleukin-1alpha [IL-1alpha], tumor necrosis factor-alpha [TNF-alpha, and TNF-beta), Th1 cytokines (interleukin-2 [IL-2], IL-12, IL-15, and IL-18), Th2 cytokines (IL-4, IL-5, and IL-10), and granulocytes-macrophage colony-stimulating factor (GM-CSF) with DNA vaccine constructs leads to modulation of the magnitude and direction (humoral or cellular) of the immune responses. To further engineer the immune response in vivo, we compared the induction and regulation of immune responses from the codelivery of chemokine (IL-8, interferon-gamma-inducible protein-10 [gammaIP-10], macrophage inhibitory protein-1alpha [MIP-1alpha], and RANTES) genes with codelivery of cytokine genes. We found that as in cytokine gene codelivery, coimmunization with chemokine genes along with DNA immunogen constructs can modulate the direction and magnitude of induced immune responses. We observed that coimmunization with IL-8, gammaIP-10, and MIP-1alpha genes increased the antibody response. We also found that coinjection with IL-8, gammaIP-10, and RANTES resulted in a dramatic enhancement of T helper (Th) proliferation response. Furthermore, among all coinjection combinations, we found that RANTES coinjection caused a high level of cytotoxic lymphocyte (CTL) enhancement. This enhancement of CTL responses observed from the coinjection with RANTES was CD8+ T cell dependent. Together with earlier reports on the utility of coimmunizing immunologically important molecules with DNA immunogens, we demonstrate the potential of this strategy as an important tool for the development of more rationally designed vaccines.

Modulation of antigen-specific humoral responses in rhesus macaques by using cytokine cDNAs as DNA vaccine adjuvants

An important limitation of DNA immunization in nonhuman primates is the difficulty in generating high levels of antigen-specific antibody responses; strategies to enhance the level of immune responses to DNA immunization may be important in the further development of this vaccine strategy for humans. We approached this issue by testing the ability of molecular adjuvants to enhance the levels of immune responses generated by multicomponent DNA vaccines in rhesus macaques. Rhesus macaques were coimmunized intramuscularly with expression plasmids bearing genes encoding Th1 (interleukin 2 [IL-2] and gamma interferon)- or Th2 (IL-4)-type cytokines and DNA vaccine constructs encoding human immunodeficiency virus Env and Rev and simian immunodeficiency virus Gag and Pol proteins. We observed that the cytokine gene adjuvants (especially IL-2 and IL-4) significantly enhanced antigen-specific humoral immune responses in the rhesus macaque model. These results support the assumption that antigen-specific responses can be engineered to a higher and presumably more desirable level in rhesus macaques by genetic adjuvants.

An alternative pathway of nitric oxide production by rat astrocytes requires specific antigen and T cell contact

In the present study, we observed an alternative pathway in which nitric oxide (NO) production by rat astrocytes requires specific antigen and cell-cell contact. NO production by astrocytes was significantly inhibited by antibodies against CD40L, B7-1 or B7-2. Astrocyte-derived NO inhibited T cell proliferation and induced T cell apoptosis. In contrast, augmented astrocyte proliferation was correlated to the levels of NO production by astrocytes, implicating a role of NO in regulating local immune responses in the central nervous system. These results suggest that T cell-astrocyte interactions may regulate local immune responses via the NO pathway and influence the fate of infiltrating T cells.

Coimmunization with IFN-gamma or IL-2, but not IL-13 or IL-4 cDNA can enhance Th1-type DNA vaccine-induced immune responses in vivo

As we explore the potential improvements to the current DNA vaccine strategies, it may be desirable to investigate methods to improve the level of resulting immune responses. One strategy is the use of cytokine cDNA as molecular adjuvants for DNA-based vaccines. Codelivery of these molecular adjuvants consisting of expression plasmid encoding for cytokines with DNA vaccine constructs is an effective method to modulate the magnitude and direction (humoral or cellular) of the immune responses. We have previously reported on the immunomodulatory effects of codelivering cDNA for interleukin-2 (IL-2) and IL-4 as molecular adjuvants for DNA-based vaccines. In this report, we extend these finding and compare the immunomodulatory effects of IL-2 and IL-4 with those of cDNA for prototypical Thl-type cytokine interferon-y (IFN-gamma) and Th2-type cytokine IL-13. We observed that distinct antigen-specific immune modulation can be achieved by the coinjection of IFN-gamma or IL-13 genes with DNA immunogen cassettes. We observed that IFN-gamma is a strong driver of Thl immune responses. Furthermore, in contrast to previous reports on their similarities in biologic activities, IL-13 and IL-4 cDNA coimmunizations modulated vaccine-induced immune responses differently in this model. Overall, these results further support the potential utility of this strategy as an important tool for the development of vaccines and immune therapies.

[Hemodynamic changes of pulmonary circulation during HDT -30 degrees]

OBJECTIVE

To study the hemodynamic changes of pulmonary circulation during simulated weightlessness.

METHOD

12 subjects were studied using echocardiography and electrocardiography during head-down tilt (HDT) of -30 degrees lasting for 45 min.

RESULT

Right ventricular ejection time increased significantly (P<0.05); peak velocity of pulmonary arterial blood flow decreased significantly (P<0.05); acceleration time of pulmonary arterial blood flow did not change significantly; significant decrease of right ventricular output occurred at the 10th minute and the 30th minute (P<0.05); pre-ejection period significantly decreased at the 30th minute and recovery. Heart rate, mean velocity of pulmonary arterial blood flow, and acceleration of pulmonary arterial blood flow did not change significantly; left ventricular cardiac output, stroke volume and blood pressure remained constant throughout the experiment.

CONCLUSION

Changes of the parameters of pulmonary circulation suggested that pulmonary resistance increased, and the increase of pulmonary resistance maybe be the direct cause of the increase of pulmonary arterial pressure.

Macrophage colony-stimulating factor can modulate immune responses and attract dendritic cells in vivo

Studies have indicated that professional APCs in the periphery, such as dendritic cells and macrophages, play an important role in initiating DNA vaccine-specific immune responses. To engineer the immune response induced by DNA vaccines in vivo we investigated the modulatory effects of codelivering growth factor genes for the hematopoietic APCs along with DNA vaccines. Specifically, we examined the effects on the antigen-specific immune responses following the codelivery of the gene expression cassettes for M-CSF, G-CSF, and GM-CSF along with HIV-1 DNA immunogen constructs. We observed that coimmunization with GM-CSF increased the antibody response and resulted in a significant enhancement of lymphoproliferative response. Furthermore, among all coinjection combinations, we found that M-CSF coinjections resulted in a high level of CTL enhancement. This enhancement of CTL responses observed from the coinjection with M-CSF was CD8+ T cell dependent and was associated with the presence of CD11c+ cells at the site of injection and with the antigen-specific induction of the beta-chemokine MIP-1beta, suggesting a role for this chemokine in CTL induction. These results suggest that hematopoietic growth factors should be further studied as potential adjuvants for in vivo modulators of immune responses.

Increase in signal intensities on T1-weighted magnetic resonance images in asymptomatic manganese-exposed workers

OBJECTIVES

To clarify the clinical significance of increased signal intensities on T1 weighted magnetic resonance imaging (MRI) we performed a large-scale epidemiological study on asymptomatic manganese (Mn)-exposed workers with its focus on MRI.

METHODS

We randomly selected 121 male workers out of a total of 750 workers including Mn-exposed, non-exposed manual, and non-exposed clerical workers in the factories. We studied environmental and biological monitoring, neurological examination, and MRI.

RESULTS

The proportion of workers with increased signal intensities among the exposed, the non-exposed manual workers, and the non-exposed clerical workers was 46.1%, 18.8%, and 0%, respectively. Especially, 73.5% of the welders showed increased signal intensities. In no subject, were clinical signs of manganism observed. The pallidal index correlated with blood Mn concentration.

CONCLUSION

Increase in signal intensities on the T1-weighted image reflect recent exposure to Mn, but not necessarily manganism. At which increase of signal intensity, the progression of manganism from Mn exposure occurs, remains to be solved.

Congenital multiple plaque-like glomangiomyoma

Congenital glomus tumor is a rare clinical variant of glomus tumor, and glomangiomyoma is the least frequent histologic type of glomus tumor. We report a case of congenital multiple plaque-like glomangiomyoma in a 38-year-old man with multiple nodules and plaques on his left arm and forearm. Histopathologic study showed an angiomatous, nonencapsulated tumor with numerous highly folded dilated vascular lumina scattered throughout the dermis. The lumina were lined by a single layer of flat endothelial cells, and one to several rows of glomus cells were observed adjacent to the endothelial cells. Around large vessels, there was a gradual transition from glomus cells to elongated mature smooth muscle cells with thin and long "blunt-ended" nuclei. Immunohistochemically, there were strong positive reactions for cytoplasmic alpha-smooth muscle actin in glomus cells and smooth muscle cells, vimentin in glomus cells and endothelial cells, and desmin in the smooth muscle cells only. To our knowledge, this is the first case report of congenital multiple plaque-like glomus tumor with the microscopic appearance of a glomangiomyoma.

Simultaneous analysis of hemoglobin adducts of acrylamide and glycidamide by gas chromatography-mass spectrometry

Acrylamide (AA) is a carcinogen in experimental animals. Glycidamide (GA), formed by metabolic epoxidation of AA, is believed to be responsible for the carcinogenicity of AA. Occupational exposure to AA has been assessed earlier by measurement of its adducts with N-terminal valine in hemoglobin. A background of AA adducts [N-(2-carbamoylethyl)valine (AAVal), about 30 pmol/g globin] was found in individuals without known exposure to the compound. The method previously available for adducts of GA only allowed analysis of samples from highly exposed individuals and showed similar levels of AAVal and adducts of GA [N-(2-hydroxy-2-carbamoylethyl)valine (GAVal)]. We have developed a sensitive method for simultaneous quantification of adducts of GA and AA, which is suitable down to low exposure levels. The method is based on the so-called modified Edman method, where globin is reacted with pentafluorophenyl isothiocyanate under neutral conditions. The valine adducts are then extracted in the form of pentafluorophenylthiohydantoin (PFPTH) derivatives. The analytical procedure included reaction of the PFPTH derivatives with acetic anhydride in order to protect the hydroxyl group of GAVal. The PFPTH derivatives of AAVal and GAVal were analyzed by gas chromatography/tandem mass spectrometry. ((2)H(3))AAVal-PFPTH was used as the internal standard. The method was applied to samples from 11 workers at an AA production plant, 1 nonexposed nonsmoker, and a few participants of a smoking cessation program. AAVal levels were in the range 27-1854 pmol/g globin. Recorded levels of GAVal were 3-12% of those of AAVal, suggesting that previous measurements of GAVal overestimate GAVal at low levels of exposure to AA.

Evaluation of exposure to ethylene glycol monoethyl ether acetates and their possible haematological effects on shipyard painters

OBJECTIVES

To evaluate exposure to mixed solvents containing ethylene glycol monoethyl ether acetate (EGEEA) in shipyard painters, to determine if EGEEA is toxic to the bone marrow.

METHODS

An industrial hygiene survey was performed to identify exposure to EGEEA of two groups of shipyard painters, a low exposure group (n = 30) and a high exposure group (n = 27). Urinary ethoxyacetic acid and methyl hippuric acid as well as haemoglobin, packed cell volume, red cell indices, total and differential white blood cell counts (WBCs), and platelet count for the shipyard painters and the control subjects were measured.

RESULTS

The mean (range) exposure concentration (ppm) to EGEEA in the high and low exposure groups were 3.03 (not detectable to 18.27), 1.76 (not detectable to 8.12), respectively. The concentrations of methyl hippuric acid and ethoxyacetic acid in the high exposure group were significantly higher than those in the control group. The mean WBCs in the high exposure group were significantly lower than in the control group, and a significant proportion, six (11%) of the 57 painters, were leucopenic; none of the controls were affected.

CONCLUSION

The high rate of possible haematological effects among shipyard painters and a hygienic evaluation of their working environment in the present study suggests that EGEEA might be toxic to bone marrow.

[Star figure in medical monitoring during lower body negative pressure test]

Objective. To find a real-time, quick and audio-visual method to evaluate the subject's physiological function condition and possible development. Method. Star figure technique was adopted to analyse multiple physiological indices during lower body negative pressure test (LBNP). Based on the character and stability of the stars figure, the steadiness of the subjects physiological function can be judged. Result. Physiological function can be accurately assessed only when the model of stress response of an individual is formed. Conclusion. The changes of star figure can indicate the possible development of the physiological function stage.

Retroactive DNA analysis for sex determination and dystrophin gene by polymerase chain reaction with archived cytogenetic slides

We describe a rapid and efficient diagnostic method for sex determination and the dystrophin gene by the polymerase chain reaction (PCR) using archived cytogenetic slides. Archived cytogenetic slides stored for about 4 years at room temperature were used. To confirm whether DNA analysis is possible using the archived cytogenetic slides, we extracted the DNA from the slides and amplified the Y centromeric region (DYZ3), the X centromeric region (DXZ1) and the exon 46 of the dystrophin gene. Of the 50 cases, 24 were peripheral bloods, 13 were amniotic fluid cells, 5 were chorionic villus samplings and 8 were cord bloods. The PCR related sex determination in 22 females and 28 males, showed 100% concordance with the results of chromosome analysis, and all cases showed positive band for the exon 46 of the dystrophin gene. Of the 50 cases of the archived cytogenetic slides, we were fortunate enough to obtain the fresh blood sample from one fetus whose karyotype showed 45,X[34]/46,X,+mar[145] to compare the results of the gDNA with that from archived cytogenetic slide. To confirm whether the marker chromosome was derived from Y chromosome, we studied the six loci (PABY, SRY, RPS4Y (SY16, 17), ZFY, DYS14) on the short arm, one locus (DYZ3) on the centromere and one locus (DYZ1) on the long arm. Of the 8 loci studies, all PCR related Y chromosome showed positive band from both gDNA obtained from cord blood and archived cytogenetic slides. We could conclude from the above results that the marker chromosome was derived from the Y chromosome. We believe our experiment is rapid and efficient for studies of over 10 independent loci from a single slide which has been kept in storage for up to 4 years and that archival Giemsa-stained cytogenetic slide repositories represent valuable DNA resources for clinical and forensic studies.

Flavonoid glycosides from Thalictrum przewalskii

A new flavonoid glycoside, 5,7-dihydroxy-4'-methoxyflavone-7-O-[6-O-(4-O-acetyl-alpha-L-rhamnosyl)-3-O-beta-D-glucosyl]-6-O-acetyl-beta-D-glucoside and three known flavonoid glycosides, 5,7-dihydroxy-4-methoxyflavone-7-0-[6-0-(4-0-acetyl-alpha-L-rhamnosyl)]-beta-D-glucoside, 3,5,7, 4'-tetrahydroxyflavonol-3-O-beta-D-glucoside and 5,7-dihydroxy-4'-methoxyflavone-7-O-(6-O-alphaL-rhamnosyl)-beta-D-glucoside were isolated from the whole plant of Thalictrum przewalskii. Their structures were determined on the basis of spectroscopic evidences.

[New ellagic glycosides and known triterpenoids from Duchesnea indica Focke]

Two new ellagic glycosides, named ducheside A and ducheside B, have been isolated from Ducheside indica Focke. Their structures were established as 3'-O-methyl-ellagic acid-4-O-beta-D-xylopyranoside (I), 3'-O-methyl-ellagic acid-4-O-alpha-L-arabinofuranoside (II), respectively, on the basis of chemical method and spectral analysis. In addition, four known compounds were isolated and identified as 3 beta-hydroxylurs-12-en-28-oic acid (III), 2 alpha, 3 beta, 19 alpha-trihydroxylurs-12-en-28-oic acid (IV), 2 alpha, 3 beta, 19 alpha-trihydroxylurs-12-en-28-oic acid 28-O-beta-D-glucopyranoside (V), 2 alpha, 3 alpha, 19 alpha-trihydroxylurs-12-en-28-oic acid 28-O-beta-D-glucopyranoside (VI). Compounds IV, V, VI were isolated for the first time from Duchesnea genus.

Xanthones from Hypericum japonicum and H. henryi

From the aerial part of Hypericum japonicum, one new xanthone glycoside, 1,5-dihydroxyxanthone-6-O-beta-D-glucoside, one novel dimer xanthone, bijaponicaxanthone, and the first natural prenylated xanthone, 1,3,5,6-tetrahydroxy-4-prenylxanthone, were isolated together with the four known xanthones, 1,5,6-trihydroxyxanthone, isojacereubin, 6-deoxyisojacareubin and 4',5'-dihydro-1,5,6-trihydroxy-4',4',5'-trimethylfurano (2',3':4,5) xanthone. five previously known xanthones, kielcorin, cadensin, 1,7,-dihydroxyxanthone, 1,5-dihydroxy-4-methoxyxanthone and 1,2,5-trihydroxyxanthone were also found in the dichoromethane extract of the stems and leaves of H. henryi. Their structures were elucidated by spectroscopic and chemical methods. Some of the compounds from H. japonicum were found to exert an interesting coagulant activity in an in vitro test. The chemotaxonomic value of xanthones is discussed briefly.

Effects of gamma irradiation on the flavor composition of food commodities

Fifteen food products including potato, sweet potato, shallot, onion, garlic, ginger, papaya, mango, rice, tobacco, small red bean, mungbean, soybean, wheat, flour and spices have been approved for irradiation by the National Health Administration in Taiwan. Market tests (Wu et al., 1996) provided strong proof that Taiwanese consumers would accept irradiated foods. However, researchers in the food industry are concerned about the possibility of chemical changes, especially in volatile composition, during irradiation processing. This study considers several food commodities, including garlic, ginger, shiitake, onion, potato, day-lily, tilapia, silver carp and shrimp. Food samples were irradiated with optimum doses and then studied for possible occurrence of chemical changes and effects on compositional characteristics of foods.

An anti-LFA-1 monoclonal antibody (LDA-8) induces cellular aggregation of human lymphoblastoid cell lines and peripheral blood lymphocytes

The human leukocyte-function-associated antigen-1 (LFA-1) plays a key role in intercellular adhesion interactions of the immune response. A monoclonal antibody (mab), designated LDA-8, is described that recognizes LFA-1. In contrast to nearly all other anti-LFA-1 mabs, which inhibit cellular aggregation, LDA-8 induces cell-cell aggregation. The LDA-8 mab was generated by immunizing mice with membrane fragments from the Jurkat T-cell line. The LDA-8 mab stained peripheral blood mononuclear cells (PBMC), monocyte-depleted peripheral blood lymphocytes, purified monocytes, and a number of T and B tumor cell lines. The LDA-8 mab induced aggregation of PBMC from normal donors, as well as of cells from T-cell lines (MOLT4 and CEM). Control mabs directed against HLA class 1 or CD4 did not induce aggregation. Aggregation was concentration- and time-dependent. EDTA added to the cultures 1 hour prior to or together with the LDA-8 mab did not inhibit LDA-8-induced aggregate formation. Anti LFA-1 alpha-chain mab added to the cells 1 hour prior to LDA-8 mab, or together with the LDA-8 mab, also did not inhibit LDA-8-induced aggregation. In contrast, anti-LFA-1 beta-chain mab, added to the cells together with or 1 hour prior to the LDA-8 mab, significantly inhibited LDA-8-induced aggregate formation. The LDA-8 mab immunoprecipitated two polypeptide chains of 110 kDa and 160 kDa under non-reducing conditions and of 92 kDa and 162 kDa under reducing conditions, from cells of the MOLT-4 or CEM T-cell lines or phytohemagglutinin (PHA)-stimulated PBMC. The molecular mass of these polypeptides was identical to that of polypeptides immunoprecipitated by the anti-LFA-1 TS1.22 mab, suggesting that the LDA-8 mab and the anti-LFA-1 mab recognize the same molecule. This was confirmed by sequential immunoprecipitation. The LDA-8 mab recognizes a unique epitope on LFA-1 and induces cell aggregation that is blocked by mabs recognizing the beta-chain, but not the alpha-chain of the LDA-1 molecule.

Comparison of human liver and small intestinal glutathione S-transferase-catalyzed busulfan conjugation in vitro

The apparent oral clearance of busulfan has been observed to vary as much as 10-fold in the population of children and adults receiving high-dose busulfan. The only identified elimination pathway for busulfan involves glutathione conjugation. The reaction is predominantly catalyzed by glutathione S-transferase (GST) A1-1, which is present in both liver and intestine. The purpose of this study was to compare busulfan Vmax/Km in cytosol prepared from adult human liver and small intestine. Tetrahydrothiophenium ion formation rate per milligram of cytosolic protein was constant along the length (assessed in 30-cm segments) of three individual small intestines. A 30-cm-long intestinal segment 90-180 cm from the pylorus was chosen to be representative of intestinal cytosolic busulfan conjugating activity. Busulfan Vmax/Km (mean +/- SD) in cytosol prepared from 23 livers and 12 small intestines was 0.166 +/- 0.066 and 0.176 +/- 0.085 microl/min/mg cytosolic protein, respectively, in incubations with 5 microM busulfan, 1 mM glutathione, and 2 mg of cytosolic protein. The relative content of GSTalpha (A1-1, A1-2, and A2-2) was compared for human liver and intestinal cytosol using Western blot. The levels of GSTalpha in liver and intestinal cytosol were 1.12 +/- 0.56 and 1.36 +/- 0.32 integrated optimal density units/5 microg cytosolic protein, respectively. Busulfan conjugation in vitro was comparable per milligram of cytosolic protein in liver and intestinal cytosol.

Lentiviral vectors for gene therapy of cystic fibrosis

A replication-defective vector based on human immunodeficiency virus (HIV) was evaluated for gene transfer directed to the lung. The tropism of this vector has been expanded through the incorporation of the vesticular stomatitis virus G protein into its envelope. The HIV vector effectively transduced nondividing airway epithelial cells in vitro whereas a murine-based retroviral vector did not. Experiments in a human bronchial xenograft model demonstrated high-level gene transduction with a cystic fibrosis transmembrane conductance regulator (CFTR) HIV vector into undifferentiated, cystic fibrosis (CF)-derived cells of the xenograft. CFTR expression was stable and capable of functional correction of the CF defect after the graft matured. The HIV vector did not effectively transduce cells of the xenograft when instilled after the epithelium had differentiated. This block to transduction appears to be at the level of entry, although post entry restrictions cannot be ruled out. Further development of this vector system for CF gene therapy should focus on a better understanding of potential entry and post entry blocks.