This study compared the ability of three forms of vitamin E [tocotrienol-rich fraction (TRF), alpha-tocopherol (α-T), and delta-tocotrienol (δ-T3)] to enhance immune response to tetanus toxoid (TT) immunisation in a mouse model. Twenty BALB/c mice were divided into four groups of five mice each. The mice were fed with the different forms of vitamin E (1 mg) or vehicle daily for two weeks before they were given the TT vaccine [4 Lf] intramuscularly (i.m.). Booster vaccinations were given on days 28 and 42. Serum was collected (days 0, 28, and 56) to quantify anti-TT levels. At autopsy, splenocytes harvested were cultured with TT or mitogens. The production of anti-TT antibodies was augmented (P < 0.05) in mice that were fed with δ-T3 or TRF compared to controls. The production of IFN-γ and IL-4 by splenocytes from the vitamin E treated mice was significantly (P < 0.05) higher than that from controls. The IFN-γ production was the highest in animals supplemented with δ-T3 followed by TRF and finally α-T. Production of TNF-α was suppressed in the vitamin E treated group compared to vehicle-supplemented controls. Supplementation with δ-T3 or TRF can enhance immune response to TT immunisation and production of cytokines that promote cell-mediated (TH1) immune response.
This paper describes a rare case of Coats disease with late presentation in a young adult. The condition improved with a combination of focal photocoagulation, cryotherapy and intravitreal ranibizumab.
The hybridoma 192 was used to produce a monoclonal antibody (MAb) against 17-hydroxyprogesterone (17-OHP), for possible use in screening for congenital adrenal hyperplasia (CAH). The factors influencing the MAb production were screened and optimized in a 2 L stirred bioreactor. The production was then scaled up to a 20 L bioreactor. All of the screened factors (aeration rate, stirring speed, dissolved oxygen concentration, pH, and temperature) were found to significantly affect production. Optimization using the response surface methodology identified the following optimal production conditions: 36.8°C, pH 7.4, stirring speed of 100 rpm, 30% dissolved oxygen concentration, and an aeration rate of 0.09 vvm. Under these conditions, the maximum viable cell density achieved was 1.34 ± 0.21 × 10(6) cells mL(-1) and the specific growth rate was 0.036 ± 0.004 h(-1) . The maximum MAb titer was 11.94 ± 4.81 μg mL(-1) with an average specific MAb production rate of 0.273 ± 0.135 pg cell(-1) h(-1) . A constant impeller tip speed criterion was used for the scale-up. The specific growth rate (0.040 h(-1) ) and the maximum viable cell density (1.89 × 10(6) cells mL(-1) ) at the larger scale were better than the values achieved at the small scale, but the MAb titer in the 20 L bioreactor was 18% lower than in the smaller bioreactor. A change in the culture environment from the static conditions of a T-flask to the stirred bioreactor culture did not affect the specificity of the MAb toward its antigen (17-OHP) and did not compromise the structural integrity of the MAb.
The effectiveness of influenza vaccination in preventing illness is lower in the elderly; this is why the ability of Lactobacillus plantarum CECT 7315/7316 to stimulate the response to influenza vaccination in elderly was evaluated.
Envenomation by hump-nosed pit viper (Hypnale hypnale, Hh) in Sri Lanka has caused significant morbidity and mortality, attributed to 35% of total venomous snakebites. In Southwestern India (Kerala), H. hypnale was increasingly identified as a dangerous and common source of envenomation, second to the Russell's viper but ahead of the cobra bites. Unfortunately, there is still no specific antivenom to date. This study aims to investigate the immunological properties of the venom and to assess the feasibility of specific Hh antivenom production as well as the development of a diagnostic assay. Hh venom elicited satisfactory titers of anti-Hh IgG in rabbits after 3rd immunization. The anti-Hh IgG, isolated with caprylic acid precipitation method, was effective in neutralizing the venom lethality (potency=48 LD(50) per ml IgG) as well as its procoagulant, hemorrhagic and necrotic effects, indicating the possibility to produce the specific antivenom using the common immunization regime. Cross-reactivity studies using indirect ELISA showed that anti-Hh IgG cross-reacted extensively with several Asiatic crotalid venoms, particularly that of Calloselasma rhodostoma (73.6%), presumably due to the presence of venom antigens common to both snakes. Levels of immunological cross-reactivity were vastly reduced with double-sandwich ELISA. Further work demonstrated that the assay was able to distinguish and quantify venoms of H. hypnale, Daboia russelii and Echis carinatus sinhaleyus (three common local viperid) used to spike human sera at various concentrations. The assay hence may be a useful investigating tool for diagnosing biting species and studying the time course profile of venom concentrations in blood.
Matched MeSH terms: Antibodies, Neutralizing/isolation & purification; Antibodies, Neutralizing/therapeutic use
To report a unique case of crystallisation in the anterior chamber and subretinal space in a Malay lady following inadvertent subretinal injection of ranibizumab prior to vitrectomy for proliferative diabetic retinopathy.
Brucellosis is a zoonotic disease which can be transmitted by direct or indirect contact with infected animal or their products. It is an important public health problem but little is known on brucellosis in the Malaysian population. The aim of this study was to determine the presence of Brucella antibodies using commercial Brucella IgG and IgM ELISA kits (Vircell, SL, Barcelona Spain). A total of 184 sera from suspected patients were received from 16 hospitals in Malaysia over the years 2004 to 2009. Only 10 serum samples (5.4%) were positive for Brucella antibodies in which 5 showed the presence of both IgM and IgG. Most of the positive patients were occupationally involved with animals. This study suggests the seroprevalance of brucellosis among individuals who have contact with infected animals in Malaysia is low.
BACKGROUND: To investigate the associations between HLA-DRB1 shared epitope (SE) alleles and rheumatoid arthritis in subsets of rheumatoid arthritis defined by autoantibodies in three Asian populations from Malaysia.
METHODS: 1,079 rheumatoid arthritis patients and 1,470 healthy controls were included in the study. Levels of antibodies to citrullinated proteins (ACPA) and rheumatoid factors were assessed and the PCR-SSO method was used for HLA-DRB1 genotyping.
RESULTS: The proportion of ACPA positivity among Malay, Chinese and Indian rheumatoid arthritis patients were 62.9%, 65.2% and 68.6%, respectively. An increased frequency of SE alleles was observed in ACPA-positive rheumatoid arthritis among the three Asian ethnic groups. HLA-DRB1*10 was highly associated with rheumatoid arthritis susceptibility in these Asian populations. HLA-DRB1*0405 was significantly associated with susceptibility to rheumatoid arthritis in Malays and Chinese, but not in Indians. HLA-DRB1*01 did not show any independent effect as a risk factor for rheumatoid arthritis in this study and HLA-DRB1*1202 was protective in Malays and Chinese. There was no association between SE alleles and ACPA- negative rheumatoid arthritis in any of the three Asian ethnic groups.
CONCLUSION: The HLA-DRB1 SE alleles increase the risk of ACPA-positive rheumatoid arthritis in all three Asian populations from Malaysia.
Helicobacter pylori is recognized as a major case of gastritis and peptic ulcer and a key factor in the development of gastric cancer, gastric lymphoma, and non-ulcerative dyspepsia in man. The detection of antibodies specific for strains of H. pylori has demonstrated the value of serology for providing evidence of infection. The present study was conducted to detect the antigenic proteins of excretory antigen of H. pylori with Western blotting and examine whether anti-H. pylori IgG and IgA antibodies from H. pylori positive patients cross-react with antigens from other common bacterial pathogens. By using SDS-PAGE, 20 different proteins were found in the excretory antigen. By Western blotting and absorption studies, there were indications that anti-H. pylori IgA antibodies directed against 54 kDa, 50 kDa and 27 kDa cross-reacted with antigens from other bacteria, and that H. pylori proteins of 99 kDa, 88 kDa and 81 kDa possibly shared similar epitope with antigens of other pathogens not tested in the absorption studies. The cross-reactivity occurred in this study was not significantly affect the performance of the in-house ELISA.
Toxoplasma gondii infects all warm-blooded animals including humans, causing serious public health problems and great economic loss in the food industry. Commonly used serological tests involve preparation of whole Toxoplasma lysate antigens from tachyzoites which are costly and hazardous. An alternative method for better antigen production involving the prokaryotic expression system was therefore used in this study. Recombinant dense granular protein, GRA2, was successfully cloned, expressed, and purified in Escherichia coli, BL21 (DE3) pLysS. The potential of this purified antigen for diagnosis of human infections was evaluated through western blot analysis against 100 human serum samples. Results showed that the rGRA2 protein has 100 and 61.5 % sensitivity towards acute and chronic infection, respectively, in T. gondii-infected humans, indicating that this protein is useful in differentiating present and past infections. Therefore, it is suitable to be used as a sensitive and specific molecular marker for the serodiagnosis of Toxoplasma infection in both humans and animals.
A chromatographic immunoassay cholera antigen detection kit, the Cholera Spot test, was evaluated. The test was found to be specific with a sensitivity of 10(6) cfu/ml for the direct detection of V. cholerae in simulated stool specimens and 10 cfu/ml in simulated cotton-tipped swab specimens after overnight incubation in alkaline peptone water. This enables early recognition of cholera cases and their contacts so that prevention and control measures can be promptly instituted.
Between February and April, 1999, an outbreak of viral encephalitis occurred among pig-farmers in Malaysia. We report findings for the first three patients who died.
Sera from fifty subjects with different presentations of Brugian filariasis and from common soil-transmitted helminth infections were tested for specific anti-filarial IgG and its subclasses. Anti-filarial IgG, IgG1 and IgG3 showed cross-reactivities with soil-transmitted helminthic infections and no significant differences in optical densities among the various groups of filarial patients. In comparison with other groups of subjects, IgG4-ELISA of sera from microfilaraemic patients and some previously microfilaraemic patients showed a significant increase in optical density readings, while IgG2-ELISA showed elevated optical density readings in sera of patients with chronic elephantiasis. Therefore IgG2-ELISA is potentially useful in the diagnosis of brugian chronic elephantiasis while IgG4-ELISA may be beneficial for follow-up diagnosis of treated microfilaraemic patients.
The relationship between the standard passive mouse protection test or serum antibody titres measured by indirect haemagglutination or enzyme-linked immunosorbent assays and active protection in buffaloes immunized with different types of haemorrhagic septicaemia bacterins was investigated. Groups of 2-3 buffaloes were immunized with the bacterins currently in use in Asia, viz., broth bacterin (BB), alum precipitated vaccine (APV) and oil adjuvant vaccine (OAV) either subcutaneously (BB, APV) or intramuscularly (OAV) and challenged subcutaneously with virulent organisms at different periods post-immunization. Although the passive mouse protection and indirect haemagglutination tests carried out with the pre-challenge sera from vaccinated buffaloes revealed no relationship with active protection in buffaloes, a relationship was observed between the ELISA antibody titres and protection. In contrast, a dose-response relationship was observed between the homologous active and passive mouse protection test.
Serum samples were obtained within 3 days of capture from 106 cynomolgus monkeys (Macaca fascicularis) in peninsular Malaysia. Fifty-two monkeys were trapped on the fringes of palm oil estates and 54 in dense primary jungle. Sera were tested for antibodies to hepatitis A virus (HAV) with a commercial radioimmunoassay. Twenty-four animals had detectable serum anti-HAV activity (6 of 52 from palm oil estate sites and 18 of 54 from primary jungle sites). Among monkeys at both sites, antibody prevalence was strongly correlated with animal weight: overall only four of 69 monkeys (6%) weighing less than 2.0 kg had serum anti-HAV antibodies, while 14 of 29 (48%) weighing 2.0 to 3.9 kg, and 6 of 8 (75%) weighing 4.0 kg or more, had serum anti-HAV antibodies. These data suggest that wild cynomolgus monkeys in Malaysian jungles become infected with HAV or an HAV-like virus at a rate comparable to that of humans in the same region, and raise the possibility of a sylvatic cycle for HAV.
Matched MeSH terms: Hepatitis Antibodies/analysis*; Hepatitis A Antibodies
Lymphatic filariasis is a mosquito-borne parasitic disease responsible for morbidity and disability that affects 1.2 billion people worldwide, mainly the poor communities. Currently, filarial antigen testing is the method of choice for the detection of bancroftian filariasis, and to date, there are two commonly used tests. In the present study, a recently reported recombinant monoclonal antibody (5B) specific to BmSXP filarial antigen was used in developing an ELISA for the detection of circulating filarial antigen in sera of patients with bancroftian filariasis. The performance of the ELISA was evaluated using 124 serum samples. The ELISA was positive with all sera from microfilaremic bancroftian filariasis patients (n = 34). It also showed 100% diagnostic specificity when tested with sera from 50 healthy individuals and 40 patients with other parasitic diseases. The developed assay using the novel 5B recombinant monoclonal antibody could potentially be a promising alternative antigen detection test for bancroftian filariasis.
To determine the seroprevalence of anti-hepatitis A virus (HAV) antibodies in patients with chronic liver disease (CLD) and to justify the need for hepatitis A vaccination.
Matched MeSH terms: Hepatitis A Antibodies/blood*; Hepatitis A Antibodies/immunology
The identification of rice bacterial leaf blight disease requires a simple, rapid, highly sensitive, and quantitative approach that can be applied as an early detection monitoring tool in rice health. This paper highlights the development of a turn-off fluorescence-based immunoassay for the early detection of Xanthomonas oryzae pv. oryzae (Xoo), a gram-negative bacterium that causes rice bacterial leaf blight disease. Antibodies against Xoo bacterial cells were produced as specific bio-recognition molecules and the conjugation of these antibodies with graphene quantum dots and gold nanoparticles was performed and characterized, respectively. The combination of both these bio-probes as a fluorescent donor and metal quencher led to changes in the fluorescence signal. The immunoreaction between AntiXoo-GQDs, Xoo cells, and AntiXoo-AuNPs in the immuno-aggregation complex led to the energy transfer in the turn-off fluorescence-based quenching system. The change in fluorescence intensity was proportional to the logarithm of Xoo cells in the range of 100-105 CFU mL-1. The limit of detection was achieved at 22 CFU mL-1 and the specificity test against other plant disease pathogens showed high specificity towards Xoo. The detection of Xoo in real plant samples was also performed in this study and demonstrated satisfactory results.
A commercially available enzyme-linked immunosorbent assay (ELISA) (PanBio Dengue Screening ELISA) that utilized both immunoglobulin M (IgM) and IgG capture in the same microtiter well for the diagnosis of dengue infection was evaluated. Sensitivity in primary and secondary dengue was 95%, while specificity was 94%.
The leaves of the Mitragynine speciosia tree (also known as Kratom) have long been chewed, smoked, or brewed into a tea by people in Southeastern Asian countries, such as Malaysia and Thailand. Just this past year, the plant Kratom gained popularity in the United States as a "legal opioid" and scheduling it as a drug of abuse is currently pending. The primary alkaloid found in Kratom is a μ-opioid receptor agonist, mitragynine, whose structure contains a promising scaffold for immunopharmacological use. Although Kratom is regarded as a safe opioid alternative, here we report the LD50 values determined for its two main psychoactive alkaloids, mitragynine and 7-hydroxymitragynine, as comparable to heroin in mice when administered intravenously. Given Kratom's recent emergence in the U.S., there is currently no diagnostic test available for law enforcement or health professionals, so we sought to design such an assay. Mitragynine was used as a starting point for hapten design, resulting in a hapten with an ether linker extending from the C9 position of the alkaloid. Bacterial flagellin (FliC) was chosen as a carrier protein for active immunization in mice, yielding 32 potential monoclonal antibodies (mAbs) for assay development. Antimitragynine mAbs in the range of micro- to nanomolar affinities were uncovered and their utility in producing a convenient lateral flow detection assay of human fluid samples was examined. Antibodies were screened for binding to mitragynine, 7-hydroxymitragynine, and performance in lateral flow assays. Two monoclonal antibodies were subcloned and further purified with 93 and 362 nM affinity to mitragynine. Test strip assays were optimized with a detection cut off of 0.5 μg/mL for mitragynine in buffer and urine (reflecting projected clinically relevant levels of drug in urine), which could be beneficial to law enforcement agencies and health professionals as the opioid epidemic in America continues to evolve.