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Fulltext Seroprevalence report on tick-borne encephalitis virus and Crimean-Congo hemorrhagic fever virus among Malaysian's farm workers

Mohd Shukri M, Ling Kho K, Ghane Kisomi M, Lani R, Marlina S, Muhd Radzi SF, et al.

BMC Public Health, 2015;15:704.
PMID: 26205588 DOI: 10.1186/s12889-015-1901-4

Tick-borne encephalitis virus (TBEV) and Crimean-Congo haemorrhagic fever virus (CCHFV) are important tick-borne viruses. Despite their wide geographical distribution and ease of acquisition, the prevalence of both viruses in Malaysia is still unknown. This study was conducted to determine the seroprevalence for TBEV and CCHFV among Malaysian farm workers as a high-risk group within the population.

Matched MeSH terms: Immunoglobulin G/blood
Recombinant VP9-based enzyme-linked immunosorbent assay for detection of immunoglobulin G antibodies to Banna virus (genus Seadornavirus)

Mohd Jaafar F, Attoui H, Gallian P, Isahak I, Wong KT, Cheong SK, et al.

J Virol Methods, 2004 Mar 01;116(1):55-61.
PMID: 14715307

Banna virus (BAV, genus Seadornavirus, family Reoviridae) is an arbovirus suspected to be responsible for encephalitis in humans. Two genotypes of this virus are distinguishable: A (Chinese isolate, BAV-Ch) and B (Indonesian isolate, BAV-In6969) which exhibit only 41% amino-acid identity in the sequence of their VP9. The VP7 to VP12 of BAV-Ch and VP9 of BAV-In6969 were expressed in bacteria using pGEX-4T-2 vector. VP9 was chosen to establish an ELISA for BAV, based mainly on two observations: (i). VP9 is a major protein in virus-infected cells and is a capsid protein (ii). among all the proteins expressed, VP9 was obtained in high amount and showed the highest immuno-reactivity to anti-BAV ascitic fluid. The VP9s ELISA was evaluated in three populations: French blood donors and two populations (blood donors and patients with a neurological syndrome) from Malaysia, representing the region where the virus was isolated in the past. The specificity of this ELISA was >98%. In mice injected with live BAV, the assay detected IgG-antibody to BAV infection 21 days post-injection, which was confirmed by Western blot using BAV-infected cells. The VP9 ELISA permits to determine the sero-status of a population without special safety precautions and without any requirements to propagate the BAV. This test should be a useful tool for epidemiological survey of BAV.

Matched MeSH terms: Immunoglobulin G/blood
Preliminary study on serum immunoglobulin G responses following intramuscular inoculation of adjuvanted polyhydroxyalkanoate microparticles with Pasteurella multocida vaccine in white rats

Mohamed S, May Amelia TS, Abdullah Amirul AA, Abdul Wahid ME, Bhubalan K

Biologicals, 2021 Jun;71:51-54.
PMID: 33858743 DOI: 10.1016/j.biologicals.2021.03.002

A natural biodegradable polymer, polyhydroxyalkanoate (PHA), was adjuvanted with a vaccine seed to observe the biomaterial's ability in enhancing an immune response in rats. The adjuvant potential of PHA was tested using the whole-killed Pasteurella multocida B:2 (PMB2) vaccine in Sprague Dawley (SD) rats to detect changes in serum immunoglobulin G (IgG) and immunoglobulin M (IgM) responses. A common PHA, poly(3-hydroxybutyrate) [P(3HB)], from Bacillus megaterium UMTKB-1 was constructed into microparticles using the solvent evaporation method. Twelve SD rats were divided into four treatment groups: 1) non-treatment as negative control, 2) P(3HB) adjuvant, 3) PMB2 vaccine, and 4) adjuvanted-P(3HB)/PMB2 vaccine groups, which were intramuscularly vaccinated twice. Immunoglobulins IgG and IgM levels were used as markers of the immune response induced by the adjuvanted-P(3HB)/PMB2 vaccine and analysed over an eight-week study period. The group vaccinated specifically with adjuvanted-P(3HB)/PMB2 vaccine had higher concentrations of immunoglobulins compared to other treatment groups, hence demonstrating the potential of the adjuvant to enhance immune response. Findings showed a need to delay the delivery of the second booster dose to determine the appropriate regime for the adjuvanted-P(3HB)/PMB2 vaccine.

Matched MeSH terms: Immunoglobulin G/blood*
Fulltext Seropositivity of dengue antibodies during pregnancy

Mohamed Ismail NA, Wan Abd Rahim WE, Salleh SA, Neoh HM, Jamal R, Jamil MA

ScientificWorldJournal, 2014;2014:436975.
PMID: 25587564 DOI: 10.1155/2014/436975

Malaysia a dengue endemic country with dengue infections in pregnancy on the rise. The present study was aimed at determining dengue seroprevalence (IgG or IgM) during pregnancy and its neonatal transmission in dengue seropositive women.

Matched MeSH terms: Immunoglobulin G/blood
Fulltext The high-affinity human IgG receptor Fc gamma receptor I (FcγRI) is not associated with vascular leakage of dengue

Mohamad Zamberi Z, Zakaria Z, Abdul Aziz AT, Heng BS, Zaid M, Chong CL, et al.

J Negat Results Biomed, 2015;14:1.
PMID: 25566870 DOI: 10.1186/s12952-014-0020-6

Dengue is a major public health problem in many tropical and sub-tropical countries. Vascular leakage and shock are identified as the major causes of deaths in patients with severe dengue. Studies have suggested the potential role of Fc gamma receptors I (FcγRI) in the pathogenesis of dengue. We hypothesized that the circulating level of Fcγ receptor I could potentially be used as an indicator in assisting early diagnosis of severe dengue.

Matched MeSH terms: Immunoglobulin G/blood*
Fulltext Development and evaluation of a sensitive and specific assay for diagnosis of human toxocariasis by use of three recombinant antigens (TES-26, TES-30USM, and TES-120)

Mohamad S, Azmi NC, Noordin R

J Clin Microbiol, 2009 Jun;47(6):1712-7.
PMID: 19369434 DOI: 10.1128/JCM.00001-09

Diagnosis of human toxocariasis currently relies on serologic tests that use Toxocara excretory-secretory (TES) antigen to detect immunoglobulin G (IgG) antibodies to the larvae. In general, however, these assays do not have adequate specificity for use in countries in which other soil-transmitted helminths are endemic. The use of recombinant antigens in these assays, however, is promising for improving the specificity of the diagnosis of toxocariasis. Toward this goal, we developed an IgG4 enzyme-linked immunosorbent assay (ELISA) involving three recombinant antigens: rTES-30USM (previously produced), rTES-26, and rTES-120. The latter two antigens were produced by reverse transcription-PCR cloning; subcloned into glutathione S-transferase (GST)-tagged and His-tagged prokaryotic expression vectors, respectively; and expressed in Escherichia coli. The recombinant proteins were subsequently purified by affinity chromatography using GST and His-Trap resins. The diagnostic potential of each purified recombinant antigen was tested with various immunoglobulin classes (IgG, IgM, and IgE) and IgG subclasses. The IgG4 ELISA was determined to have the highest specificity and was further evaluated using a panel of serum samples. The rTES-26 IgG4 ELISA showed 80.0% (24/30 samples positive) sensitivity, and both the rTES-30USM IgG4 ELISA and rTES-120 IgG4 ELISA had 93.0% (28/30) sensitivity. Combined use of rTES-120 and rTES-30 IgG4 ELISA for the diagnosis of toxocariasis provided 100% sensitivity. The specificities of rTES-26, rTES-30USM, and rTES-120 antigens were 96.2%, 93.9%, and 92.0%, respectively. These results indicate that the development of a diagnostic test using the three recombinant antigens will allow for more-accurate detection of toxocariasis.

Matched MeSH terms: Immunoglobulin G/blood
Fulltext IgG4 detection of Echinococcus granulosus paramyosin is a useful diagnostic test for human hydatidosis

Moghadam ZK, Ghaffarifar F, Khalilpour A, Abdul Aziz F, Saadatnia G, Noordin R

Clin Vaccine Immunol, 2013 Apr;20(4):501-5.
PMID: 23365208 DOI: 10.1128/CVI.00019-13

Hydatidosis is a public health problem in many parts of the world, and improvement in diagnosis of the disease is still being pursued. Protoscoleces of Echinococcus granulosus were isolated from hydatid cysts collected from naturally infected sheep slaughtered in abattoirs in Iran. Sonicated extract of protoscolex was subjected to two-dimensional gel electrophoresis and Western blot analysis. Primary antibodies were from serum samples from 130 hydatidosis patients, 38 individuals infected with other parasitic infections, and 30 healthy people, whereas peroxidase (HRP)-conjugated anti-human IgG and IgG4 were used as secondary antibodies. The recombinant form of the identified protein was produced and tested for its sensitivity and specificity for the detection of human hydatidosis. An antigenic band of ∼60 kDa was found to be sensitive (82%) and specific (100%) for the detection of hydatidosis when probed with anti-human IgG4-HRP, while the sensitivity and specificity were 33 and 100%, respectively, with anti-human IgG-HRP. By mass spectrometry, the band was identified as protoscolex tegument paramyosin. The sensitivity and specificity of full-length paramyosin-recombinant protein in IgG4 blots were found to be 86 and 98%, respectively. In conclusion, IgG4 detection of Echinococcus granulosus paramyosin was found to be useful for the diagnosis of human hydatidosis.

Matched MeSH terms: Immunoglobulin G/blood*
Are ERM (ezrin/radixin/moesin) proteins targets for autoantibodies in demyelinating neuropathies?

Miyaji K, Shahrizaila N, Umapathi T, Chan YC, Hirata K, Yuki N

Hum Immunol, 2014 Nov;75(11):1089-91.
PMID: 25286001 DOI: 10.1016/j.humimm.2014.09.010

Ezrin, radixin and moesin, which are strongly expressed in the Schwann cell microvilli, are putative targets for autoantibodies in acute or chronic inflammatory demyelinating polyneuropathy (AIDP or CIDP). An association between anti-moesin IgG antibodies and cytomegalovirus-related AIDP has been postulated. None of 41 AIDP patients, including 8 cytomegalovirus-related AIDP patients, and 23 CIDP had IgG or IgM antibodies to ezrin, radixin and moesin; whereas, one patient with cytomegalovirus-related AIDP had anti-ezrin IgM antibodies. Ezrin, radixin and moesin are unlikely targets for autoantibodies in AIDP and CIDP, and the association of anti-moesin antibodies with cytomegalovirus-related AIDP was not confirmed.

Matched MeSH terms: Immunoglobulin G/blood
Fulltext Single injection recombinant vesicular stomatitis virus vaccines protect ferrets against lethal Nipah virus disease

Mire CE, Versteeg KM, Cross RW, Agans KN, Fenton KA, Whitt MA, et al.

Virol J, 2013 Dec 13;10:353.
PMID: 24330654 DOI: 10.1186/1743-422X-10-353

BACKGROUND: Nipah virus (NiV) is a highly pathogenic zoonotic agent in the family Paramyxoviridae that is maintained in nature by bats. Outbreaks have occurred in Malaysia, Singapore, India, and Bangladesh and have been associated with 40 to 75% case fatality rates. There are currently no vaccines or postexposure treatments licensed for combating human NiV infection.
METHODS AND RESULTS: Four groups of ferrets received a single vaccination with different recombinant vesicular stomatitis virus vectors expressing: Group 1, control with no glycoprotein; Group 2, the NiV fusion protein (F); Group 3, the NiV attachment protein (G); and Group 4, a combination of the NiV F and G proteins. Animals were challenged intranasally with NiV 28 days after vaccination. Control ferrets in Group 1 showed characteristic clinical signs of NiV disease including respiratory distress, neurological disorders, viral load in blood and tissues, and gross lesions and antigen in target tissues; all animals in this group succumbed to infection by day 8. Importantly, all specifically vaccinated ferrets in Groups 2-4 showed no evidence of clinical illness and survived challenged. All animals in these groups developed anti-NiV F and/or G IgG and neutralizing antibody titers. While NiV RNA was detected in blood at day 6 post challenge in animals from Groups 2-4, the levels were orders of magnitude lower than animals from control Group 1.
CONCLUSIONS: These data show protective efficacy against NiV in a relevant model of human infection. Further development of this technology has the potential to yield effective single injection vaccines for NiV infection.

Matched MeSH terms: Immunoglobulin G/blood
Fulltext Detection of Toxoplasma gondii DNA by PCR following microwave treatment of serum and whole blood

Meganathan P, Singh S, Ling LY, Singh J, Subrayan V, Nissapatorn V

Southeast Asian J. Trop. Med. Public Health, 2010 Mar;41(2):265-73.
PMID: 20578507

Detection of Toxoplasma gondii in blood by means of the polymerase chain reaction (PCR) may facilitate early diagnosis of toxoplasmosis in different groups of patients. We evaluated this approach in 42 patients presenting with ocular or psychotic diseases by comparing the sensitivity and specificity of PCR after heat treatment using a microwave oven with a standard genomic DNA extraction method for paired serum and whole blood samples. The presence of serum IgM and IgG antibodies against T. gondii was detected using a standard commercial enzyme-linked immunosorbent assay and enzyme immunoassay for IgG avidity test. Of 42 whole blood samples, PCR after microwave treatment was positive in 8 samples with a sensitivity of 73% and specificity of 100% compared to 11 samples positive by the extraction method. Although none of 42 sera samples was PCR positive by the extraction method, 7 specimens were positive after microwave treatment. This is the first study to use a microwave heat treatment, which is simple, rapid and a promising alternative method, in detecting small amounts of T. gondii DNA in human blood. Furthermore, irradiation of blood samples with microwaves allows incorporation of PCR into a practical tool for routine clinical assessment of patients with Toxoplasma infection.

Matched MeSH terms: Immunoglobulin G/blood
A high incidence of serum IgG antibodies to the Epstein-Barr virus replication activator protein in nasopharyngeal carcinoma

Mathew A, Cheng HM, Sam CK, Joab I, Prasad U, Cochet C

Cancer Immunol Immunother, 1994 Jan;38(1):68-70.
PMID: 8299121

The BamHI Z EBV replication activator (ZEBRA) protein is involved in the switch from latency to productive cycle of Epstein-Barr virus. A recombinant ZEBRA protein was synthesized and assessed in enzyme-linked immunosorbent assay (ELISA) for serum IgG response in nasopharyngeal carcinoma (NPC) patients. In 100 NPC serum samples that were positive for IgA to the EBV viral capsid antigen (VCA), 75% had IgG anti-ZEBRA antibodies. In contrast, only 3/83 (3.6%) serum samples from healthy donors and 2/50 (4%) from other cancers were positive for IgG to ZEBRA. Interestingly, in a selected group of 100 NPC sera negative for IgA to VCA, 25% contained IgG anti-ZEBRA antibodies. This suggests that the ELISA for IgG anti-ZEBRA may also identify earlier cases of NPC not detected by the conventional immunofluorescence test for IgA to VCA.

Matched MeSH terms: Immunoglobulin G/blood*
Fulltext Diagnostic value of anti-modified citrullinated vimentin in rheumatoid arthritis

Maraina CH, Nurdayana AK, Rusni D, Azwany Y

Int J Rheum Dis, 2010 Oct;13(4):335-9.
PMID: 21199468 DOI: 10.1111/j.1756-185X.2010.01552.x

BACKGROUND: Rheumatoid factors (RF) are currently used in the diagnosis of rheumatoid arthritis (RA). Several other autoantibodies found in RA are directed to epitopes in citrullinated proteins such as anti-cyclic citrullinated and recently anti-modified citrullinated vimentin (MCV).
OBJECTIVE: In this study we determined the sensitivity and specificity of anti-MCV in comparison with anti-cyclic citrullinated peptide (CCP) antibodies and RF in RA patients and in a control group using the American College of Rheumatology (ACR) criteria as the gold standard.
MATERIALS AND METHODS: A cross sectional study was conducted from January to December 2008 on 100 patients with RA and 153 patients with arthritis or arthralgia but not fulfilling ACR criteria for RA. Serum from each subject was tested for anti-MCV, anti-CCP antibodies and immunoglobulin G (IgG) RF by enzyme-linked immunosorbent assay. Sensitivity and specificity of the tests were evaluated using the ACR criteria as the gold standard.
RESULTS: The sensitivity of RF was 85% with 74.5% specificity. For anti-CCP antibodies the sensitivity was 71% and the specificity was 94.8%. The sensitivity of anti-MCV antibodies was 80% with 59.5% specificity. The area under the curve for RF was 0.759, for anti-CCP antibodies was 0.866 and for anti-MCV antibodies was 0.681, while for at least one positive test it was 0.691.
CONCLUSION: Anti-CCP antibodies have higher diagnostic specificity and positive predictive value than RF and anti-MCV antibodies. RF has the highest sensitivity when compared to anti-CCP and anti-MCV antibodies. Thus anti-MCV antibody is not a better marker when compared to RF or anti-MCV antibody in the diagnosis of RA patients.

Study site: family medicine clinic, rheumatology clinic and immunology laboratory of Hospital Universiti Sains Malaysia (HUSM), Kubang Kerian, Kelantan, Malaysia

Matched MeSH terms: Immunoglobulin G/blood*
Fulltext The role of worm infestation in allergic rhinitis

Manuel AM, Kuljit S, Gopalakrishnan G, Suresh KG, Balraj P

Trop Biomed, 2012 Sep;29(3):360-5.
PMID: 23018498 MyJurnal

The purpose of this study is to determine the relevance of the hygiene hypothesis; that is to determine if worm infestation has a protective role against the development of allergic rhinitis. A prospective case controlled study was conducted. Specific IgG levels to Toxocara were studied in 85 patients confirmed to have allergic rhinitis and were compared to levels in another 85 controls, with no form of allergy. The IgG assay was done using ELISA technique. There was a higher incidence of positive specific IgG to Toxocara in the controls as compared to allergic patients. The values were statistically significant [Chi square test (p=0.002)]. This negative association between worm infestation and allergic rhinitis suggests that a previous worm infestation could protect against the development of allergic rhinitis.

Matched MeSH terms: Immunoglobulin G/blood
Effects of supplementation with tocotrienol-rich fraction on immune response to tetanus toxoid immunization in normal healthy volunteers

Mahalingam D, Radhakrishnan AK, Amom Z, Ibrahim N, Nesaretnam K

Eur J Clin Nutr, 2011 Jan;65(1):63-9.
PMID: 20859299 DOI: 10.1038/ejcn.2010.184

Vitamin E is an essential fat-soluble vitamin that has been shown to induce favorable effects on animal and human immune systems. The objective of this study was to assess the effects of tocotrienol-rich fraction (TRF) supplementation on immune response following tetanus toxoid (TT) vaccine challenge in healthy female volunteers.

Matched MeSH terms: Immunoglobulin G/blood
A semisynthetic diterpenoid lactone inhibits NF-κB signalling to ameliorate inflammation and airway hyperresponsiveness in a mouse asthma model

Lim JC, Goh FY, Sagineedu SR, Yong AC, Sidik SM, Lajis NH, et al.

Toxicol Appl Pharmacol, 2016 07 01;302:10-22.
PMID: 27089844 DOI: 10.1016/j.taap.2016.04.004

Andrographolide (AGP) and 14-deoxy-11,12-didehydroandrographolide (DDAG), two main diterpenoid constituents of Andrographis paniculata were previously shown to ameliorate asthmatic symptoms in a mouse model. However, due to inadequacies of both compounds in terms of drug-likeness, DDAG analogues were semisynthesised for assessment of their anti-asthma activity. A selected analogue, 3,19-diacetyl-14-deoxy-11,12-didehydroandrographolide (SRS27), was tested for inhibitory activity of NF-κB activation in TNF-α-induced A549 cells and was subsequently evaluated in a mouse model of ovalbumin (OVA)-induced asthma. Female BALB/c mice, 6-8weeks old were sensitized on days 0 and 14, and challenged on days 22, 23 and 24 with OVA. Compound or vehicle (3% dimethyl sulfoxide) was administered intraperitoneally 1h before and 11h after each OVA aerosol challenge. On day 25, pulmonary eosinophilia, airway hyperresponsiveness, mucus hypersecretion, inflammatory cytokines such as IL-4, -5 and -13 in BAL fluid, gene expression of inflammatory mediators such as 5-LOX, E-selectin, VCAM-1, CCL5, TNF-α, AMCase, Ym2, YKL-40, Muc5ac, CCL2 and iNOS in animal lung tissues, and serum IgE were determined. SRS27 at 30μM was found to suppress NF-κB nuclear translocation in A549 cells. In the ovalbumin-induced mouse asthma model, SRS27 at 3mg/kg displayed a substantial decrease in pulmonary eosinophilia, BAL fluid inflammatory cytokines level, serum IgE production, mucus hypersecretion and gene expression of inflammatory mediators in lung tissues. SRS27 is the first known DDAG analogue effective in ameliorating inflammation and airway hyperresponsiveness in the ovalbumin-induced mouse asthma model.

Matched MeSH terms: Immunoglobulin G/blood
Brugia malayi infection in Meriones unguiculatus: antibody response to recombinant BmR1

Lim BH, Noordin R, Nor ZM, Rahman RA, Abdullah KA, Sinnadurai S

Exp Parasitol, 2004 Sep-Oct;108(1-2):1-6.
PMID: 15491542

BmR1 recombinant antigen has previously been shown to demonstrate high sensitivity and specificity in the serological diagnosis of brugian filariasis in humans. In this study, the pattern of recognition of antibody to BmR1 during Brugia malayi infection was investigated by employing Meriones unguiculatus as the experimental model. Thirty two gerbils were infected subcutaneously with 120 L(3); and two control groups each comprising 25 animals were employed. ELISA using BmR1 was used to detect filaria-specific IgG antibodies elicited by the gerbils; using sera collected from the day 1 until day 150 post-inoculation (p.i.). The results showed that BmR1 detected B. malayi infection in gerbils harboring adult worms irrespective of the presence of circulating microfilaria, and was exemplified by positive ELISA results in nine a microfilaraemic animals that harbored live adult worms. The initial time of the antibody recognition was at day 8 p.i. and the antibody titre showed some correlation with adult worm burden.

Matched MeSH terms: Immunoglobulin G/blood
Expression of a codon-optimised recombinant Ara h 2.02 peanut allergen in Escherichia coli

Lew MH, Lim RL

Appl Microbiol Biotechnol, 2016 Jan;100(2):661-71.
PMID: 26411458 DOI: 10.1007/s00253-015-6953-y

Current diagnostic tools for peanut allergy using crude peanut extract showed low predictive value and reduced specificity for detection of peanut allergen-specific immunoglobulin E (IgE). The Ara h 2.02, an isoform of the major peanut allergen Ara h 2, contains three IgE epitope recognition sequence of 'DPYSPS' and may be a better reagent for component resolve diagnosis. This research aimed to generate a codon-optimised Ara h 2.02 gene for heterologous expression in Escherichia coli and allergenicity study of this recombinant protein. The codon-optimised gene was generated by PCR using overlapping primers and cloned into the pET-28a (+) expression vector. Moderate expression of a 22.5 kDa 6xhistidine-tagged recombinant Ara h 2.02 protein (6xHis-rAra h 2.02) in BL21 (DE3) host cells was observed upon induction with 1 mM isopropyl β-D-1-thiogalactopyranoside (IPTG). The insoluble recombinant protein was purified under denaturing condition using nickel-nitrilotriacetic acid (Ni-NTA) affinity chromatography and refolded by dialysis in decreasing urea concentration, amounting to a yield of 74 mg/l of expression culture. Matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) and immunoblot analysis confirmed the production of the recombinant 6xHis-rAra h 2.02. The refolded recombinant 6xHis-rAra h 2.02, with or without adjuvant, was able to elicit comparable level of allergen-specific IgE and IgG1 in sensitised Balb/c mice. In addition, the specific IgE antibodies raised against the recombinant protein were able to recognise the native Ara h 2 protein, demonstrating its allergenicity and potential as a reagent for diagnosis and therapeutic study.

Matched MeSH terms: Immunoglobulin G/blood
An orally active geranyl acetophenone attenuates airway remodeling in a murine model of chronic asthma

Lee YZ, Shaari K, Cheema MS, Tham CL, Sulaiman MR, Israf DA

Eur J Pharmacol, 2017 Feb 15;797:53-64.
PMID: 28089919 DOI: 10.1016/j.ejphar.2017.01.011

2,4,6-Trihydroxy-3-geranyl acetophenone (tHGA) is a synthetic compound that is naturally found in Melicope ptelefolia. We had previously demonstrated that parenteral administration of tHGA reduces pulmonary inflammation in OVA-sensitized mice. In this study, we evaluated the effect of orally administered tHGA upon airway remodeling in a murine model of chronic asthma. Female BALB/C mice were sensitized intraperitoneally with ovalbumin (OVA) on day 0, 7 and 14, followed by aerosolized 1% OVA 3 times per week for 6 weeks. Control groups were sensitized with saline. OVA sensitized animals were either treated orally with vehicle (saline with 1% DMSO and Tween 80), tHGA (80, 40, 20mg/kg) or zileuton (30mg/kg) 1h prior to each aerosolized OVA sensitization. On day 61, mice underwent methacholine challenge to determine airway hyperresponsiveness prior to collection of bronchoalveolar lavage (BAL) fluid and lung samples. BAL fluid inflammatory cell counts and cytokine concentrations were evaluated while histological analysis and extracellular matrix protein concentrations were determined on collected lung samples. Oral tHGA treatment attenuated airway hyperresponsiveness and inhibited airway remodeling in a dose-dependent fashion. tHGA's effect on airway remodeling could be attributed to the reduction of inflammatory cell infiltration and decreased expression of cytokines associated with airway remodeling. Oral administration of tHGA attenuates airway hyperresponsiveness and remodeling in OVA-induced BALB/c mice. tHGA is an interesting compound that should be evaluated further for its possible role as an alternative non-steroidal pharmacological approach in the management of asthma.

Matched MeSH terms: Immunoglobulin G/blood
Immunogenic characterization of the chimeric surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii expressed in the yeast Pichia pastoris

Lau YL, Thiruvengadam G, Lee WW, Fong MY

Parasitol Res, 2011 Sep;109(3):871-8.
PMID: 21455621 DOI: 10.1007/s00436-011-2315-6

In this study, we successfully expressed a chimerical surface antigen 1 and 2 (SAG1/2) of Toxoplasma gondii in Pichia pastoris. Eighty human serum samples, including 60 from confirmed cases of toxoplasmosis, were tested against the purified recombinant SAG1/2 in Western blots. Results of Western blots targeted at Toxoplasma IgG and IgM showed that the recombinant SAG1/2 reacted with all sera from the toxoplasmosis cases but none with the Toxoplasma-negative serum samples. These results showed that the P. pastoris-derived recombinant SAG1/2 was sensitive and specific and suitable for use as antigen for detecting anti-Toxoplasma antibodies. To further investigate the immunological characteristic of the recombinant protein, the recombinant SAG1/2 was injected subcutaneously into BALB/c mice, and their serum was tested against total protein lysate of T. gondii. Mice immunized with the recombinant SAG1/2 reacted specifically with the native SAG1 and SAG2 of T. gondii. Significant proliferation of splenocytes stimulated with tachyzoite total protein lysate was observed in vaccinated BALB/c mice but not in those from negative control mice. Specific production of IFN-γ, the Th1-type cytokines, was also found in stimulated splenocytes from vaccinated mice. These results show that the chimeric protein recombinant SAG1/2 can elicit a Th1-associated protection against T. gondii infections in mice. Finally, vaccinated mice were significantly protected against lethal challenge with live T. gondii RH strain tachyzoites (P

Matched MeSH terms: Immunoglobulin G/blood
Toxoplasma gondii: serological characterization and immunogenicity of recombinant surface antigen 2 (SAG2) expressed in the yeast Pichia pastoris

Lau YL, Fong MY

Exp Parasitol, 2008 Jul;119(3):373-8.
PMID: 18457835 DOI: 10.1016/j.exppara.2008.03.016

The full length surface antigen 2 (SAG2) gene of the protozoan parasite Toxoplasma gondii was cloned and intracellularly expressed in the Pichia pastoris expression system. The molecular weight of the expressed recombinant SAG2 (36 kDa) was much larger than the native SAG2 (22 kDa). This discrepancy in size was due to hyperglycosylation, as deglycosylation assay reduced the size of the recombinant SAG2 to 22 kDa. Despite being hyperglycosylated, the recombinant SAG2 reacted strongly with pooled anti-Toxoplasma human serum, pooled anti-Toxoplasma mouse serum and a SAG2-specific monoclonal antibody. The glycosylated recombinant SAG2 was further evaluated in Western blot and in-house enzyme-linked immunosorbent assay (ELISA) using 80 human serum samples, including confirmed early acute (IgM positive, IgG negative; n=20), acute (IgM positive, IgG positive; n=20) and chronic (IgM negative, IgG positive; n=20) toxoplasmosis patients, and toxoplasmosis negative control patients (n=20). Results of the Western blot showed that the recombinant SAG2 reacted with all 60 samples of the toxoplasmosis cases but not with the Toxoplasma-negative samples. The sensitivity of in-house ELISA was 80%, 95% and 100% for early acute, acute and chronic patients' serum samples, respectively. Vaccination study showed that serum from mice immunised with the glycosylated recombinant SAG2 reacted specifically with the native SAG2 of T. gondii. The mice were significantly protected against lethal challenge with live T. gondii RH strain tachyzoites (P<0.01) and their survival time was increased compared to controls. Therefore, the present study shows that the P. pastoris-derived recombinant SAG2 was specific and suitable for use as antigen for detecting anti-Toxoplasma IgG and IgM antibodies. The vaccination study showed that recombinant SAG2 protein was immunoprotective in mice against lethal challenge.

Matched MeSH terms: Immunoglobulin G/blood

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