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M Zhu

Publications and source records attributed to M Zhu.

At least 19 recordsLinked to original sources
PubMed2002

Bacterial distribution and phylogenetic diversity in the Changjiang estuary before the construction of the Three Gorges Dam.

The bacterial community structure in the Changjiang estuary was studied for comparison with future changes, related to the construction of the Three Gorges Dam. Population densities of bacteria in the surface water at station C1 estimated by CFU on marine agar plates and by DAPI direct count, were 2.8 x 10(4) ml(-1) and 4.2 x 10(5) ml(-1), respectively. Physicochemical properties of water, such as temperature and salinity, suggested that station C1 was affected by freshwater from the Changjiang River. Cluster analysis of the PCR-RFLP patterns obtained from 9 samples showed that the bacterial community structure at station C1 was different from the structure at the other stations. Bacterial diversity in the surface water at station C1 was studied based on the genotypes of the 250 clones of 16S rRNA, and on the phenotypes generated on Biolog GN plates for 70 isolates. Sequences of bacteria from two common marine groups, alpha- and gamma-Proteobacteria, were frequently observed. Some other divisions, including the beta-Proteobacteria, C/F/B group, low G+C gram positive, high G+C gram positive, chloroplasts, and relatives of Verrucomicrobia were also observed. The putative dominant species based on both genotype and phenotype analyses were close relatives of Alteromonas macleodii or Roseobacter spp. These results reflected the nutrient-rich environment at station C1.

Bacteria↗
PubMed2002

Determination of toxicokinetic parameters for bioconcentration of water-soluble fraction of petroleum hydrocarbon associated with no. 0 diesel in Changjiang estuary and Jiaozhou bay: model versus mesocosm experiments.

A method is proposed for determination of toxicokinetic parameters for bioconcentration by phytoplankton of the water-soluble fraction (WSF) of petroleum hydrocarbon (PH) associated with No. 0 diesel, in which WSF-PH concentration in phytoplankton cells, C(A(d)), is estimated by subtracting concentration in water (S-bottle) containing a phytoplankton sample from that in a C-bottle without phytoplankton. It was demonstrated that C(A(d)) agrees well with the concentration found by direct ultrasonication extraction of collected cells, C(A(ind)) ( r = 0.88, p < 0.0001), and its uncertainty was about 17.6%. Mesocosms in 25-m3 ethylene vinyl acetate or 4-m3 polyethylene bags were performed at two sites in China: Changjiang Estuary in spring/summer 1998 and Jiaozhou Bay in autumn 1999 and spring/summer 2000. The experiments were designed to determine toxicokinetic parameters, including specific rates of uptake and elimination, and bioconcentration factor (BCF), for bioconcentration of WSF-PH by phytoplankton. A modified kinetic two-compartment model for bioconcentration of WSF-PH by phytoplankton was developed to estimate the toxicokinetic parameters. In the model, the influence of phytoplankton growth on bioconcentration and WSF-PH decline due to biotic and abiotic processes other than bioconcentration, such as volatilization, microbial degradation, phytolysis, and sorption expressed as an exponential-decay equation, are taken into account. Size-dependent BCF was observed in the laboratory experiment. BCFs were 1.0 x 10(4) in summer in Changjiang Estuary, 1.6 x 10(4) in summer, and 1.1 x 10(4) in autumn in Jiaozhou Bay. The difference in BCF may be interpreted by its size dependence.

Biological Availability↗
PubMed2002

Extraction of lipids from Mortierella alpina and enrichment of arachidonic acid from the fungal lipids.

Mortierella alpina is known as an arachidonic acid (AA) producing oleaginous fungus. Extraction of lipids from wet and dry M. alpina biomass was compared. Lipids yield of extraction from dry cells was higher than that of extraction from wet. Wet extraction mainly extracted lipid bodies and lipids in membranes did not extract effectively. Enrichment of AA from the fungal lipids by a urea inclusion method was studied. Most of the saturated and monounsaturated fatty acids, 93.0% and 84.6%, respectively, were removed by forming urea inclusion compounds. AA was concentrated after urea inclusion. Its content in total fatty acids increased 6.2-folds and reached 57.1% with a recovery of 81.9%.

Arachidonic Acid↗
PubMed2002

Neuromuscular disorders associated with static lumbar flexion: a feline model.

Static flexion of the lumbar spine with constant load applied to the viscoelastic structures for 20 minutes and for 50 minutes resulted in development of spasms and inhibition in the multifidus muscles (e.g., deep erector spinae) and in creep of the supraspinous ligament in the feline model. The development of spasms and inhibition was not dependent on load magnitude. It is suggested that occupational and sports activities which require prolonged static lumbar flexion within the physiological range can cause a "sprain"-like injury to the ligaments, which in turn reflexively induce spasms and inhibition in some erector spinae muscles. Such disorder may take a long time to recover, in the order of days to weeks, depending on the level of creep developed in the tissues.

Animals↗
PubMed2002

Population pharmacokinetics of ethionamide in patients with tuberculosis.

SETTING: Three US referral hospitals. OBJECTIVE: Determine the population pharmacokinetic (PK) parameters of ethionamide (ETA) following multiple oral doses. DESIGN: Fifty-five patients with tuberculosis (TB) participated. Patients received multiple oral doses of ETA as part of their treatment. They also received other anti-tuberculosis medications based upon in vitro susceptibility data. Serum samples were collected over 12 h post-dose, and concentrations were determined using a validated high-performance liquid chromatography (HPLC) assay. Concentration-time data were analyzed using population methods. RESULTS: ETA areas under the concentration-versus-time curve (AUCs) increased linearly with increasing oral doses from 250 to 1000 mg. Compared to the population pattern, delayed absorption was seen at least once in 15% of patients. ETA PK parameter estimates were independent of age, weight, height, gender, and creatinine clearance. TB patients appeared to have larger volumes of distribution (3.22 l/kg) and clearance values (1.88 l/h/kg) compared to previously studied healthy volunteers. This resulted in lower AUC values (3.95 mcg h/ml) in the TB patients. ETA displayed a short elimination half-life (1.94 h). The effect of different dosing strategies on calculated pharmacodynamic parameters was explored. Simulated doses of 250 mg BID to TID failed to achieve serum concentrations above the MIC. CONCLUSION: ETA PK parameters differed between TB patients and healthy volunteers, possibly due to differences in the completeness of absorption. Doses of at least 500 mg appear to be required to achieve serum concentrations above the typical ETA MIC. Additional research is needed to determine the optimal dosing of ETA.

Administration, Oral↗
PubMed2001

Functional characterization of transcription regulators that interact with the electrophile response element.

The electrophile response element (EpRE), also referred to as the antioxidant responsive element (ARE), is found in the 5'-regulatory region of a number of genes encoding phase II, drug-metabolizing enzymes. Gene knockout studies have demonstrated the primary regulatory role that an Nrf2:Maf dimer plays by binding to nucleotides within the EpRE consensus sequence. Current models of transcription regulation have also shown the involvement of higher-order transcriptional coactivators, proteins that nucleate around DNA sequence-specific transcription factors, enhancing transcription of the target gene by interacting with components of the basal transcriptional apparatus and by enabling chromatin remodeling. Here, we hypothesized that multiple transcriptional regulators, including: (i) a primary Nrf2-Maf heterodimer, (ii) a proposed secondary, EpRE-specific, p160 family coactivator, ARE-binding protein-1, and (iii) a tertiary coactivator, CBP/p300, nucleate to form a complex at the EpRE that regulates transcription of the dependent gene. To test this hypothesis, we constructed a HepG2 cell line which contains a stably integrated green fluorescent protein (GFP) gene; its inducible expression is regulated by a synthetic TK promoter containing a linked EpRE. To identify the involvement of specific, primary and higher-order transcriptional regulators in the EpRE-mediated regulation of the GFP reporter gene, we microinjected antibodies directed against specific transcription factors into the HepG2/GFP cells and determined their effect upon tBHQ-induced expression of the GFP gene. The results demonstrate that microinjected antibodies directed against Nrf2, MafK, CBP and p300 could each, individually, significantly inhibit tBHQ-induced GFP expression. This directly demonstrates the role that the tertiary regulators, CBP or p300, play in mediating EpRE activation of phase II genes, and also implicates the involvement of secondary, p160 family coactivators. Moreover, we found that the same anti-MafK antibody that blocked induction of the EpRE-regulated GFP gene completely ablated the gel-shift complex that we hypothesize contains an Nrf2:Maf dimer, ARE-binding protein-1, and CBP or p300.

Base Sequence↗
PubMed2001

The infection of human dendritic cells with recombinant avipox vectors expressing a costimulatory molecule transgene (CD80) to enhance the activation of antigen-specific cytolytic T cells.

Human dendritic cells (DCs) express MHC class I and II molecules and several T-cell costimulatory molecules that contribute to their efficiency as antigen-presenting cells (APCs). Whereas most human DC populations uniformly express some costimulatory molecules such as B7-2 (CD86), previous studies have shown a wide variation in the expression of B7-1 (CD80) among different human DC preparations. In the studies reported here, we demonstrate that replication-defective avipox vectors expressing B7-1 can be used to rapidly and efficiently infect human DCs and can enhance the efficacy of human DCs to activate specific human T-cell populations. This has been demonstrated both in systems using peptide as a source of signal 1 and in systems using recombinant avipox vector to deliver signal 1. The antigen used in these studies was the tumor-associated human carcinoembryonic antigen (CEA). An immunodominant 9-mer CTL epitope for CEA (designated CAP-1) has been previously characterized (K. Y. Tsang et al., J. Natl. Cancer Inst. (Bethesda), 87: 982-990, 1995). The source of signal 1 used in these studies was (a) the CAP-1 peptide; (b) recombinant avipox-CEA; or (c) the dual transgene recombinant avipox-CEA/B7-1. These studies demonstrate that CEA-specific T cells are more efficiently activated using as APCs peptide-pulsed DCs infected with avipox-B7-1, as compared with peptide-pulsed DCs infected with wild-type vector, or with uninfected peptide-pulsed DCs. Greater activation of CEA-specific T cells was also obtained using as APCs DCs that were infected with avipox-CEA/B7-1 as compared with the use of DCs infected with avipox-CEA. A CEA tetramer was also used to isolate high- and low-tetramer-binding CEA-specific T-cell populations. Although both high- and low-tetramer-binding T cells had the ability to lyse CEA peptide-pulsed targets, only the high-tetramer-binding T cells had the ability to lyse colon carcinoma cells expressing CEA, which suggests the existence of tetramer-binding populations with different T-cell receptor (TCR) affinities. The demonstrated safety of recombinant avipox vectors in humans and the previously demonstrated ability to administer them multiple times without host immune response limitations indicate that these vectors expressing B7-1 have a potential use in enhancing the efficacy of human DC immunotherapy protocols using either peptide or recombinant vector to deliver signal 1.

Antigen Presentation↗
PubMed2001

High-performance liquid chromatographic method for simultaneous determination of hawthorn active components in rat plasma.

A simple HPLC method with photodiode-array (PDA) ultraviolet detection was developed for the simultaneous determination of four active polyphenol components of hawthorn (Crataegus), chlorogenic acid, epicatechin, hyperoside and isoquercitrin, in rat plasma. Following extraction from the plasma samples with ethyl acetate-methanol (2:1, v/v), these four compounds were successfully separated using a C18 column with a gradient elution of 5 and 25% acetonitrile in 25 mM phosphate buffer (pH 2.4). The flow-rate was set at 1 ml/min and the eluent was detected at 325 nm for chlorogenic acid, 278 nm for epicatechin, and 360 nm for both hyperoside and isoquercitrin. Narignin (0.82 microg) was used as the internal standard and was detected at 278 nm. The method is linear over the studied range of 0.16-40, 0.63-160, 0.13-32 and 0.13-30 microg/ml for chlorogenic acid, epicatechin, hyperoside and isoquercitrin, respectively. The correlation coefficient for each analyte was greater than 0.995. The intra-day and inter-day precision of the analysis was better than 4 and 7%, respectively. The extraction recoveries at low to high concentration were greater than 85% for both epicatechin and chlorogenic acid, and greater than 94% for both hyperoside and isoquercitrin. The detection limits were 0.04, 0.20, 0.03 and 0.03 microg/ml for chlorogenic acid, epicatechin, hyperoside and isoquercitrin. The developed method was used to analyze the plasma concentrations of the four analytes after the intravenous administration of hawthorn polyphenol extract to rats.

Animals↗
PubMed2001

Changes of the expression of 5-HT receptor subtype mRNAs in rat dorsal root ganglion by complete Freund's adjuvant-induced inflammation.

By using the reverse transcriptase polymerase chain reaction technique, the expression of 5-hydroxytryptamine (5-HT) receptor subtype mRNAs in the rat lumbar dorsal root ganglion (DRG) was investigated following unilateral injection of complete Freund's adjuvant (CFA) into the rat hind paw. The results showed that 5-HT(1A), 5-HT(1B), 5-HT(1D), 5-HT(1F), 5-HT(2A), 5-HT(3), 5-HT(4), 5-HT(5A) and 5-HT(7) receptor subtypes were present in the rat lumbar DRG. CFA injection resulted in a significant increase in mRNA level of 5-HT(1A), 5-HT(1B), 5-HT(1F), 5-HT(2A), 5-HT(3), 5-HT(4) and 5-HT(7) receptor subtypes and a marked induction of 5-HT(2C) subtype mRNA in the DRG. The present results suggest the important roles for these 5-HT receptor subtypes in generating peripheral nociceptive signaling and provide evidence to elucidate the mechanism of 5-HT in nociception.

Actins↗
PubMed2001

Enhanced activation of human T cells via avipox vector-mediated hyperexpression of a triad of costimulatory molecules in human dendritic cells.

T-cell activation usually requires at least two signals. The first signal is antigen-specific, and the second signal(s) involves the interaction of a T-cell costimulatory molecule(s) on the antigen-presenting cell (APC) with its ligand on the T cell. Dendritic cells (DCs) are the most potent APCs, attributable, in part, to their expression of several T-cell costimulatory molecules. Human DCs generated in vitro, however, will vary in methods of generation and maturation and in terms of expression of different phenotypic markers-including costimulatory molecules-among different donors. We report here that a recombinant avipox (fowlpox, rF) vector has been constructed that can efficiently express the transgenes for three human T-cell costimulatory molecules (B7-1, ICAM-1, and LFA-3) as a result of individual early avipox promoters driving the expression of each transgene. This triad of costimulatory molecules (designated TRICOM) was selected because each has an individual ligand on T cells and each has been shown previously to prime a unique signaling pathway in T cells. We report here that rF-TRICOM can efficiently infect human DCs of different states of maturity and hyperexpress each of the three costimulatory molecules on the DC surface without affecting other DC phenotypic markers. Infection of influenza or human papilloma virus 9-mer peptide-pulsed DCs from different individuals, or at different stages of maturity with rF-TRICOM, resulted in enhanced activation of T cells from peripheral blood mononuclear cells of autologous donors after 24 h of incubation with DCS: This enhanced activation was analyzed by both titrating the peptide and differing the DC:effector cell ratios. No effect was observed using the control wild-type avipox vector. No increase in apoptosis was observed in T cells hyperstimulated with the TRICOM vector, and no decrease in interleukin-12 production was seen in lipopolysaccharide-stimulated DCs infected with rF-TRICOM. Antibody-blocking experiments demonstrated that enhanced T-cell activation by TRICOM was attributed to each of the three costimulatory molecules. Peptide-pulsed, rF-TRICOM-infected DCs were also shown to be more effective than peptide-pulsed DCs in activating T cells to 9-mer peptides derived from two relatively weak "self" immunogens, i.e., human prostate-specific antigen and human carcinoembryonic antigen. These studies thus demonstrate for the first time that a vector that can simultaneously hyperexpress three costimulatory molecules can be used to efficiently infect human DCs, leading to enhanced peptide-specific T-cell activation. The use of this approach for in vitro studies and clinical applications in immunotherapy is discussed.

B7-1 Antigen↗
PubMed2001

Polymorphic electrophile response elements in the mouse glutathione S-transferase GSTa1 gene that confer increased induction.

Induced transcription of a battery of stress response genes in mammals, including several phase I and phase II drug-metabolizing enzymes, is regulated by the electrophile responsive element (EpRE). Because previous directed mutagenesis of nucleotide motifs within the large, composite EpRE were shown to affect transcription factor binding and associated induced expression of dependent genes, we hypothesized that naturally-occurring variation or polymorphism in the EpRE sequence, if found, could affect the induced expression of important protective genes like glutathione S-transferases, and that this could be an important determinant of cancer risk in humans and other mammals. To determine whether this occurred in nature, 32 strains and species of inbred mice were screened to examine the EpRE sequence present in the mGSTa1 promoter. Two species, Mus caroli and Mus spretus, showed TGAC-->TGGC mutations in the tandem TGAC motif. Inducibility (15-fold) of the variant Mus spretus EpRE sequence in a reporter gene construct in HepG2 cells was significantly increased versus the wild-type EpRE sequence (8-fold). A comparison of mGSTa1-induced expression in the livers of Mus spretus, Mus caroli, and BALB/cJ mice showed the highest level of mGSTa1 mRNA in livers from the Mus spretus and Mus carolimice. This naturally-occurring polymorphism within the EpRE domain is the first mutation with an associated phenotype to be reported within a promoter regulatory element of a drug metabolizing gene.

Animals↗
PubMed2001

A primitive sarcopterygian fish with an eyestalk.

The discovery of two Early Devonian osteichthyan (bony fish) fossils has challenged established ideas about the origin of osteichthyans and their divergence into actinopterygians (teleosts and their relatives) and sarcopterygians (tetrapods, coelacanths, lungfishes and related groups). Psarolepis from China and an unnamed braincase from Australia combine derived sarcopterygian and actinopterygian characters with primitive features previously restricted to non-osteichthyans, suggesting that early osteichthyan evolution may have involved substantial parallellism between sarcopterygians and actinopterygians. But interpretation of these fossils has been hampered by poor phylogenetic resolution. Here we describe a basal sarcopterygian fish, Achoania gen, et sp. nov., that fills the morphological gap between Psarolepis and higher sarcoptergyians. We also report the presence of eyestalk attachments in both Achoania and Psarolepis, showing that this supposedly non-osteichthyan feature occurs in basal sarcopterygians as well as the actinoptergyian-like Australian braincase.

Animals↗
PubMed2001

Studies using leukemia inhibitory factor (LIF) knockout mice and a LIF adenoviral vector demonstrate a key anti-inflammatory role for this cytokine in cutaneous inflammation.

Previous work has implicated the cytokine leukemia inhibitory factor (LIF) in cutaneous inflammation, although results have differed as to whether LIF is pro- or anti-inflammatory in this setting. We examined edema, inflammatory cell infiltration, and cytokine responses following CFA injection in the adult mouse footpad. Inflammatory cell infiltration and edema are significantly enhanced when CFA is injected in LIF knockout mice as compared with injection of wild-type littermates. Moreover, local injection of an adenoviral vector encoding LIF suppresses both measures of inflammation. In contrast, injection of an adenoviral vector encoding beta-galactosidase has no discernable effect on inflammation. In addition, comparison of the CFA responses in LIF knockout vs wild-type skin reveals that LIF is an important regulator of IL-1beta, IL-6, IL-7, IL-2Ralpha, and IFN-gamma in cutaneous inflammation. These and our previous data indicate that both endogenous and exogenous LIF are anti-inflammatory in the CFA model and that LIF is a key regulator of the cytokine cascade. The results also indicate that adenoviral gene delivery can be an effective therapeutic approach in this paradigm.

Adenoviridae↗
PubMed2001

Characterization of antioxidants present in hawthorn fruits.

Hawthorn fruit extract has been shown to have many health benefits including being cardiovascular protective, hypotensive and hypocholesterolemic. The present study was carried out to characterize further the antioxidants of hawthorn fruit and their effect on the oxidation of human low density lipoprotein (LDL) and alpha-tocopherol. The dry hawthorn fruit was extracted successively with ether, ethyl acetate, butanol and water. The ethyl acetate fraction was only effective in inhibition of Cu(+2)-mediated LDL oxidation. The column chromatographic separation led to isolation of eight pure compounds; namely, ursolic acid, hyperoside, isoquercitrin, epicatechin, chlorogenic acid, quercetin, rutin and protocatechuic acid. All of these phenolic compounds, except ursolic acid, were protective to human LDL from Cu(+2)-mediated LDL oxidation. They were also effective in preventing the peroxy free radical-induced oxidation of alpha-tocopherol in human LDL. The inhibitory effect of these compounds on oxidation of LDL and alpha-tocopherol was dose-dependent at concentrations ranging from 5 to 40 µM. In addition, supplementation of 2% hawthorn fruit powder significantly elevated serum alpha-tocopherol by 18-20% in rats fed a 30% polyunsaturated canola oil diet, as compared with the control. The present results suggest that part of the mechanism for cardiovascular protective effects of hawthorn fruit might also involve the direct protection to human LDL from oxidation or indirect protection via maintaining the concentration of alpha-tocopherol in human LDL.

Journal Article↗
PubMed2001

A methylene blue-mediated enzyme electrode for the determination of trace mercury(II), mercury(I), methylmercury, and mercury-glutathione complex.

A methylene blue-mediated enzyme biosensor has been developed for the detection of inhibitors including mercury(II), mercury(I), methylmercury, and mercury-glutathione complex. The inhibition to horseradish peroxidase was apparently reversible and noncompetitive in the presence of HgCl2 in less than 8 s and irreversibly inactivated when incubated with different concentrations of HgCl2 for 1-8 min. The binding site of horseradish peroxidase with HgCl2 probably was a cysteine residue SH. Mercury compounds can be assayed amperometrically with the detection limits 0.1 ng ml(-1) Hg for HgCl2 and methylmercury, 0.2 ng ml(-1) Hg for Hg2(NO3)2 and 1.7 ng ml(-1) Hg for mercury glutathione complex. Inactivation of the immobilized horseradish peroxidase was displayed in the AFM images of the enzyme membranes.

Biosensing Techniques↗
PubMed2001

Temporal relationships among uterine pituitary adenylate cyclase-activating polypeptide, decidual prolactin-related protein and progesterone receptor mRNAs expressions during decidualization and gestation in rats.

Pituitary adenylate cyclase-activating peptide (PACAP), a novel compound with vasoactive intestinal polypeptide-like activity, was recently shown to be localized in the neuronal endings of the human uterus. The purpose of the present study was to assess the functional presence of PACAP mRNA in the decidual endometrium and its relationship to the expression levels of decidual prolactin-related protein (dPRP) and the progesterone receptor mRNAs during decidualization and pregnancy in Sprague-Dawley rats. PACAP was constitutively and temporally expressed in the decidual endometrium and gravid uterus. The time-dependent correlated expression levels of PACAP, dPRP and the progesterone receptor were induced by the neurogenic reproductive signals, i.e. the vagino-cervical/deciduogenic stimuli of decidualization and by the normal equivalent stimuli of mating/blastocyst implantation of gestation. Correlation among the mRNA expression levels of PACAP, dPRP and the progesterone receptor and the coordinated inhibitory actions of the anti-progesterone (RU-486) suggest that there is also correlated time-dependent steroid regulation of the mRNA levels of PACAP, dPRP and the progesterone receptor in the decidual and pregnant uteri. One possible functional meaning for the time-related localization of endometrial/uterine PACAP could be to facilitate endometrial blood flow and increase the availability of metabolic substrates to the developing deciduoma or embryo. The study demonstrates the potential importance of PACAP expression in the regulation of the maternal feto-placental component and suggests a prominent reproductive role for the neuropeptide in mammalian pregnancy.

Animals↗
PubMed2001

HIV epitope-peptides in aluminum adjuvant induced high levels of epitope-specific antibodies.

Some neutralizing epitopes on HIV-1 envelope proteins were shown to induce antibodies that could effectively inhibit the infection of different HIV-1 strains in vitro. But only very low levels of antibodies to these epitopes were determined in the HIV-1 infected individuals. In this study, the aluminum (alum) adjuvant to increase the immunogenicity of the neutralizing epitopes was used. Three epitope-peptides [C-(ELDKWAG)4, C-(RILAVERYLKD-G)2 and C-(GPGRAFY)2], which contain three epitopes (ELDKWA, RILAVERYLKD, GPGRAFY) from the HIV-1 Env proteins, were synthesized and conjugated to carrier protein keyhole limpet hemocyanin (KLH). The epitope-vaccines C-(ELDKWAG)4-KLH and C-(RILAVERYLKD-G)2-KLH in alum induced high levels of epitope-specific antibodies recognizing the epitopes from epitope-peptides C-(ELDKWAG)4 and C-(RILAVERYLKD-G)2, as well as the gp41 C-domain peptides P2 [C-TSLIHSLIEESQNQQEKNEQELLELDKWA (aa 646-674)] and P1 [LQARILAVERYLKDQQL (aa 583-599)] and the recombinant soluble gp41 (rsgp41) bearing both epitopes (antibody titer in rabbit sera was 1:12800-25,600 dilution). Immunoblotting analysis demonstrated that the antibodies in both antisera bound to rsgp41, indicating that both antibodies recognized the natural epitopes on rsgp41 protein. The epitope-vaccines C-(GPGRAFY)2-KLH induced moderate GPGRAFY epitope-specific antibody response with a titer of 1:6,400. In contrast, as it was demonstrated in previous studies, the immunization with rgp160 induced weak antibody response to these three epitopes (titer of 1:400-1600). This suggests that epitope-peptides conjugated to KLH when infected with alum significantly increases immunogenicity of gp41 neutralizing epitopes providing a hope for the development of an HIV-1 vaccine.

AIDS Vaccines↗