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1.
Malays J Med Sci ; 30(6): 5-21, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38239252

RESUMO

Forensic DNA typing has been widely accepted in the courts all over the world. This is because DNA profiling is a very powerful tool to identify individuals on the basis of their unique genetic makeup. DNA evidence is capable of not only identifying the presence of specific biospecimens in a crime scene, but it is also used to exonerate suspects who are innocent of a crime. Technological advancements in DNA profiling, including the development of validated kits and statistical methods have made this tool to be more precise in forensic investigations. Therefore, validated combined DNA index system (CODIS) short tandem repeats (STRs) kits which require very small amount of DNA, coupled with real-time polymerase chain reaction (PCR) and the statistical strengths are used routinely to identify human remains, establish paternity or to match suspected crime scene biospecimens. The road to modern DNA profiling has been long, and it has taken scientists decades of work and fine tuning to develop highly accurate testing and analyses that are used today. This review will discuss the various DNA polymorphisms and their utility in human identity testing.

2.
Curr Issues Mol Biol ; 44(12): 5866-5878, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36547060

RESUMO

Carcinoscorpius rotundicauda (C. rotundicauda) is one of the four species of horseshoe crabs (HSCs). The HSC hemocytes store defense molecules that are released upon encountering invading pathogens. The HSCs rely on this innate immunity to continue its existence as a living fossil for more than 480 million years. To gain insight into the innate mechanisms involved, transcriptomic analysis was performed on isolated C. rotundicauda hemocytes challenged with lipopolysaccharides (LPS), the main components of the outer cell membrane of gram-negative bacteria. RNA-sequencing with Illumina HiSeq platform resulted in 232,628,086 and 245,448,176 raw reads corresponding to 190,326,253 and 201,180,020 high-quality mappable reads from control and LPS-stimulated hemocytes, respectively. Following LPS-stimulation, 79 genes were significantly upregulated and 265 genes were downregulated. The differentially expressed genes (DEGs) were related to multiple immune functional categories and pathways such as those of the cytoskeleton, Toll and Imd, apoptosis, MAP kinase (MAPK), inositol phosphate metabolism, phagosome, leucocyte endothelial migration, and gram-negative bacterial infection, among others. This study provides important information about the mechanisms of response to LPS, which is relevant for the understanding the HSCs' immune response.

3.
Int J Mol Sci ; 23(15)2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35955665

RESUMO

Tuberculosis remains a major threat to global public health, with more than 1.5 million deaths recorded in 2020. Improved interventions against tuberculosis are urgently needed, but there are still gaps in our knowledge of the host-pathogen interaction that need to be filled, especially at the site of infection. With a long history of infection in humans, Mycobacterium tuberculosis (Mtb) has evolved to be able to exploit the microenvironment of the infection site to survive and grow. The immune cells are not only reliant on immune signalling to mount an effective response to Mtb invasion but can also be orchestrated by their metabolic state. Cellular metabolism was often overlooked in the past but growing evidence of its importance in the functions of immune cells suggests that it can no longer be ignored. This review aims to gain a better understanding of mucosal immunometabolism of resident effector cells, such as alveolar macrophages and mucosal-associated invariant T cells (MAIT cells), in response to Mtb infection and how Mtb manipulates them for its survival and growth, which could address our knowledge gaps while opening up new questions, and potentially be applied for future vaccination and therapeutic strategies.


Assuntos
Células T Invariantes Associadas à Mucosa , Mycobacterium tuberculosis , Tuberculose , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Tuberculose/microbiologia
4.
Malays J Med Sci ; 29(2): 1-7, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35528817

RESUMO

Cholera, a diarrheal disease caused by Vibrio cholerae (V. cholerae) O139 and O1 strains, remains a public health problem. The existing World Health Organization (WHO)-licenced, killed, multiple-dose oral cholera vaccines demand 'cold-chain supply' at 2 °C-8 °C. Therefore, a live, single-dose, cold-chain-free vaccine would relieve significant bottlenecks and costs of cholera vaccination campaigns. Our cholera vaccine development journey started in 2000 at Universiti Sains Malaysia with isolation of the hemA gene from V. cholerae, followed by development of a gene mutant vaccine candidate VCUSM2 against V. cholerae O139 in 2006. In 2010, VCUSM2 reactogenicity was reduced by replacing its two wild-type ctxA gene copies with mutated ctxA to produce strain VCUSM14. Introducing the hemA gene into VCUSM14 created VCUSM14P, a strain with the 5-aminolaevulinic acid (ALA) prototrophic trait and excellent colonisation and immunological properties (100% protection to wild-type challenged rabbits). It was further refined in Asian Institute of Medicine, Science and Technology (AIMST University), with completion of single- and repeated-dose toxicity evaluations in 2019 in Sprague Dawley (SD) rats, followed by development of a novel cold-chain-free VCUSM14P formulation in 2020. VCUSM14P is unique for its intact cholera toxin B, a known mucosal adjuvant. The built-in adjuvant makes VCUSM14P an ideal vaccine delivery platform for emerging diseases (e.g. severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] and tuberculosis). Our vaccine formulation mimics natural infection, remains non-reactogenic and immunogenic in vivo, and protects against infection and disease. It will also cost less and be less cumbersome to distribute due to its stability at room temperature. These features could revolutionise the outreach of this and other vaccines to meet global immunisation programmes, particularly in low-resourced areas. The next stage of our journey will be meeting the requisite regulatory requirements to produce the vaccine for rollout to countries where it is most needed.

5.
Fish Shellfish Immunol ; 117: 148-156, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34358702

RESUMO

Horseshoe crabs (HSCs) are living fossil species of marine arthropods with a long evolutionary history spanning approximately 500 million years. Their survival is helped by their innate immune system that comprises cellular and humoral immune components to protect them against invading pathogens. To help understand the genetic mechanisms involved, the present study utilised the Illumina HiSeq platform to perform transcriptomic analysis of hemocytes from the HSC, Tachypleus gigas, that were challenged with lipopolysaccharides (LPS). The high-throughput sequencing resulted in 352,077,208 and 386,749,136 raw reads corresponding to 282,490,910 and 305,709,830 high-quality mappable reads for the control and LPS-treated hemocyte samples, respectively. Based on the log-fold change of > 0.3 or < -0.3, 1338 genes were significantly upregulated and 215 genes were significantly downregulated following LPS stimulation. The differentially expressed genes (DEGs) were further identified to be associated with multiple pathways such as those related to immune defence, stress response, cytoskeleton function and signal transduction. This study provides insights into the underlying molecular and regulatory mechanisms in hemocytes exposed to LPS, which has relevance for the study of the immune response of HSCs to infection.


Assuntos
Hemócitos/efeitos dos fármacos , Caranguejos Ferradura/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Transcriptoma/efeitos dos fármacos , Animais , Perfilação da Expressão Gênica , Caranguejos Ferradura/genética
6.
Nanomedicine ; 34: 102374, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33675981

RESUMO

Despite recent advances in diagnosis, tuberculosis (TB) remains one of the ten leading causes of death worldwide. Here, we engineered Mycobacterium tuberculosis (Mtb) proteins (ESAT6, CFP10, and MTB7.7) to self-assemble into core-shell nanobeads for enhanced TB diagnosis. Respective purified Mtb antigen-coated polyester beads were characterized and their functionality in TB diagnosis was tested in whole blood cytokine release assays. Sensitivity and specificity were studied in 11 pulmonary TB patients (PTB) and 26 healthy individuals composed of 14 Tuberculin Skin Test negative (TSTn) and 12 TST positive (TSTp). The production of 6 cytokines was determined (IFNγ, IP10, IL2, TNFα, CCL3, and CCL11). To differentiate PTB from healthy individuals (TSTp + TSTn), the best individual cytokines were IL2 and CCL11 (>80% sensitivity and specificity) and the best combination was IP10 + IL2 (>90% sensitivity and specificity). We describe an innovative approach using full-length antigens attached to biopolyester nanobeads enabling sensitive and specific detection of human TB.


Assuntos
Antígenos de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Nanopartículas , Tuberculose Pulmonar/diagnóstico , Citocinas/metabolismo , Humanos , Sensibilidade e Especificidade , Tuberculose Pulmonar/metabolismo
7.
Eur J Clin Microbiol Infect Dis ; 39(5): 799-826, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31853742

RESUMO

Currently, there is a trend of increasing incidence in pulmonary non-tuberculous mycobacterial infections (PNTM) together with a decrease in tuberculosis (TB) incidence, particularly in developed countries. The prevalence of PNTM in underdeveloped and developing countries remains unclear as there is still a lack of detection methods that could clearly diagnose PNTM applicable in these low-resource settings. Since non-tuberculous mycobacteria (NTM) are environmental pathogens, the vicinity favouring host-pathogen interactions is known as important predisposing factor for PNTM. The ongoing changes in world population, as well as socio-political and economic factors, are linked to the rise in the incidence of PNTM. Development is an important factor for the improvement of population well-being, but it has also been linked, in general, to detrimental environmental consequences, including the rise of emergent (usually neglected) infectious diseases, such as PNTM. The rise of neglected PNTM infections requires the expansion of the current efforts on the development of diagnostics, therapies and vaccines for mycobacterial diseases, which at present, are mainly focused on TB. This review discuss the current situation of PNTM and its predisposing factors, as well as the efforts and challenges for their control.


Assuntos
Gerenciamento Clínico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções Respiratórias/microbiologia , Animais , Ensaios Clínicos como Assunto , Saúde Global , Interações Hospedeiro-Patógeno , Humanos , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Infecções por Mycobacterium não Tuberculosas/prevenção & controle , Micobactérias não Tuberculosas , Prevalência , Infecções Respiratórias/complicações
8.
Int J Legal Med ; 132(4): 1087-1090, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29052042

RESUMO

Peninsular Malaysia is populated by the Malays, Chinese, Indians, and Orang Asli. We have analyzed 17 Y-STRs loci for 243 randomly unrelated individuals, which include 153 Malays (7 Acheh, 13 Champa, 11 Rawa, 9 Kedah, 23 Minang, 15 Bugis, 43 Kelantan, 14 Jawa, and 18 Bugis) and 90 Orang Asli [54 Semang (16 Kensiu, 13 Lanoh, 25 Bateq); 30 Senoi (21 Semai, 9 Che Wong); and 6 Proto-Malay (6 Orang Kanaq)] from selected settlements in Peninsular Malaysia using the AmpFlSTR Yfiler™ kit (Applied Biosystems™). The overall haplotype diversity is 0.9966, i.e., 0.9984 for the Malays and 0.9793 for the Orang Asli. A total of 158 haplotypes (65.02%) were individually unique. The p value and pairwise Rst analysis was calculated to show the genetic structure of the samples with other world populations (from YHRD website). Based on the Y-STR data, Champa, Acheh, Kedah, Minang, and Kelantan are clustered together. Lanoh and Kensiu (Semang) are very closely related, suggesting similar paternal ancestry. Jawa Malays and Indonesian Java, plus the Bugis Malays and Australian Aborigines shared high degree of paternal lineage affinity. This study presents data for very precious relict groups, who are the earliest inhabitants of Peninsular Malaysia.


Assuntos
Cromossomos Humanos Y , Etnicidade/genética , Genética Populacional , Repetições de Microssatélites , Impressões Digitais de DNA , Haplótipos , Humanos , Malásia/etnologia , Masculino , Reação em Cadeia da Polimerase
9.
Int J Legal Med ; 132(4): 1091, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29134364

RESUMO

The original version of this article contains an error. The Author Abd Rashid Nur Haslindawaty has been added as to the above author group as third author. The original article was corrected.

10.
Immunology ; 144(2): 302-11, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25158076

RESUMO

The acquired immune response against tuberculosis is commonly associated with T-cell responses with little known about the role of B cells or antibodies. There have been suggestions that B cells and humoral immunity can modulate the immune response to Mycobacterium tuberculosis. However, the mechanisms involving B-cell responses in M. tuberculosis are not fully understood, in particular the antibody gene preferences. We hypothesized that a preferential use of V genes can be seen associated with resistance to infection mainly in the IgA isotype, which is of prominent importance for infection by pathogens via the mucosal route. We studied healthy individuals with long-term exposure to tuberculosis, infected (TST(+) ) and uninfected TST(-) ) with M. tuberculosis. From a total of 22 V genes analysed, the TST(-) population preferred the VH 3-23 and Vκ1 genes. The VH 3-23 genes were subsequently subjected to 454 amplicon sequencing. The TST(-) population showed a higher frequency of the D3-10 segment compared with the D3-22 segment for the TST(+) population. The J segment usage pattern was similar for both populations with J4 segment being used the most. A preferential pairing of J4 segments to D3-3 was seen for the TST(-) population. The antibodyome difference between both populations suggests a preference for antibodies with VH 3-23, D3-3, JH 4 gene usage by the TST(-) population that could be associated with resistance to infection with M. tuberculosis.


Assuntos
Genes de Cadeia Pesada de Imunoglobulina , Imunoglobulina A/genética , Imunoglobulina A/imunologia , Cadeias J de Imunoglobulina/genética , Cadeias delta de Imunoglobulina/genética , Tuberculose Pulmonar/genética , Tuberculose Pulmonar/imunologia , Adulto , Antígenos CD19/genética , Antígenos CD19/imunologia , Linfócitos B/imunologia , Sequência de Bases , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cadeias J de Imunoglobulina/imunologia , Região de Junção de Imunoglobulinas/genética , Região de Junção de Imunoglobulinas/imunologia , Cadeias delta de Imunoglobulina/imunologia , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Análise de Sequência de DNA
11.
BMC Complement Altern Med ; 14: 252, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25034326

RESUMO

BACKGROUND: Development of tumour resistance to chemotherapeutic drugs and concerns over their toxic effects has led to the increased use of medicinal herbs or natural products by cancer patients. Strobilanthes crispus is a traditional remedy for many ailments including cancer. Its purported anticancer effects have led to the commercialization of the plant leaves as medicinal herbal tea, although the scientific basis for its use has not been established. We previously reported that a bioactive subfraction of Strobilanthes crispus leaves (SCS) exhibit potent cytotoxic activity against human breast cancer cell lines. The current study investigates the effect of this subfraction on cell death activities induced by the antiestrogen drug, tamoxifen, in estrogen receptor-responsive and nonresponsive breast cancer cells. METHODS: Cytotoxic activity of SCS and tamoxifen in MCF-7 and MDA-MB-231 human breast cancer cells was determined using lactate dehydrogenase release assay and synergism was evaluated using the CalcuSyn software. Apoptosis was quantified by flow cytometry following Annexin V and propidium iodide staining. Cells were also stained with JC-1 dye to determine changes in the mitochondrial membrane potential. Fluorescence imaging using FAM-FLICA assay detects caspase-8 and caspase-9 activities. DNA damage in the non-malignant breast epithelial cell line, MCF-10A, was evaluated using Comet assay. RESULTS: The combined SCS and tamoxifen treatment displayed strong synergistic inhibition of MCF-7 and MDA-MB-231 cell growth at low doses of the antiestrogen. SCS further promoted the tamoxifen-induced apoptosis that was associated with modulation of mitochondrial membrane potential and activation of caspase-8 and caspase-9, suggesting the involvement of intrinsic and extrinsic signaling pathways. Interestingly, the non-malignant MCF-10A cells displayed no cytotoxicity or DNA damage when treated with either SCS or SCS-tamoxifen combination. CONCLUSIONS: The combined use of SCS and lower tamoxifen dose could potentially reduce the side effects/toxicity of the drug. However, further studies are needed to determine the effectiveness and safety of the combination treatment in vivo.


Assuntos
Acanthaceae/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/tratamento farmacológico , Extratos Vegetais/farmacologia , Tamoxifeno/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Células MCF-7 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Tamoxifeno/administração & dosagem
12.
BMC Immunol ; 14 Suppl 1: S5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23458635

RESUMO

Recombinant Mycobacterium bovis bacille Calmette-Guèrin (rBCG) expressing three T cell epitopes of Mycobacterium tuberculosis (MTB) Ag85B antigen (P1, P2, P3) fused to the Mtb8.4 protein (rBCG018) or a combination of these antigens fused to B cell epitopes from ESAT-6, CFP-10 and MTP40 proteins (rBCG032) were used to immunize Balb/c mice. Total IgG responses were determined against Mtb8.4 antigen and ESAT-6 and CFP-10 B cell epitopes after immunization with rBCG032. Mice immunized with rBCG032 showed a significant increase in IgG1 and IgG2a antibodies against ESAT-6 and MTP40 (P1) B cell epitopes and IgG3 against both P1 and P2 B cell epitopes of MPT40. Splenocytes from mice immunized with rBCG018 proliferated against Ag85B P2 and P3 T cell epitopes and Mtb8.4 protein whereas those from mice-immunized with rBCG032 responded against all Ag85B epitopes and the ESAT-6 B cell epitope. CD4⁺ and CD8⁺ lymphocytes from mice immunized with rBCG018 produced primarily Th1 type cytokines in response to the T cell epitopes. Similar pattern of recognition against the T cell epitopes were obtained with rBCG032 with the additional recognition of ESAT-6, CFP-10 and one of the MTP40 B cell epitopes with the same pattern of cytokines. This study demonstrates that rBCG constructs expressing either T or T and B cell epitopes of MTB induced appropriate immunogenicity against MTB.


Assuntos
Antígenos de Bactérias/imunologia , Vacina BCG/imunologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Mycobacterium tuberculosis/imunologia , Aciltransferases/imunologia , Aciltransferases/metabolismo , Adjuvantes Imunológicos , Animais , Antígenos de Bactérias/metabolismo , Vacina BCG/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Epitopos de Linfócito B/biossíntese , Epitopos de Linfócito T/biossíntese , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/imunologia , Fosfolipases Tipo C/imunologia , Fosfolipases Tipo C/metabolismo , Vacinação , Vacinas Sintéticas/imunologia
13.
BMC Immunol ; 14 Suppl 1: S9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23458073

RESUMO

TB, caused by Mycobacterium tuberculosis (MTB), is one of the major global infectious diseases. For the pandemic control, early diagnosis with sensitive and specific methods is fundamental. With the advent of bioinformatics' tools, the identification of several proteins involved in the pathogenesis of TB (TB) has been possible. In the present work, the MTB genome was explored to look for molecules with possible antigenic properties for their evaluation as part of new generation diagnostic kits based on the release of cytokines. Seven proteins from the MTB proteome and some of their combinations suited the computational test and the results suggested their potential use for the diagnosis of infection in the following population groups: Cuba, Mexico, Malaysia and sub-Saharan Africa. Our predictions were performed using public bioinformatics tools plus three computer programs, developed by our group, to facilitate information retrieval and processing.


Assuntos
Proteínas de Bactérias/imunologia , Simulação por Computador , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/imunologia , Tuberculose/diagnóstico , Sequência de Aminoácidos , Antígenos de Bactérias/imunologia , Sequência de Bases , Biologia Computacional , Citocinas/biossíntese , Humanos , Proteoma , Análise de Sequência de DNA , Tuberculose/imunologia
14.
BMC Immunol ; 14 Suppl 1: S6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23458668

RESUMO

An in silico study was carried out to identify antigens for their possible collective use as vaccine candidates against diseases caused by different classes of pathogenic mycobacteria with significant clinical relevance. The genome sequences of the relevant causative agents were used in order to search for orthologous genes among them. Bioinformatics tools permitted us to identify several conserved sequences with 100% identity with no possibility of cross-reactivity to the normal flora and human proteins. Nine different proteins were characterized using the strain H37Rv as reference and taking into account their functional category, their in vivo expression and subcellular location. T and B cell epitopes were identified in the selected sequences. Theoretical prediction of population coverage was calculated for individual epitopes as well as their combinations. Several identical sequences, belonging to six proteins containing T and B cell epitopes which are not present in selected microorganisms of the normal microbial flora or in human proteins were obtained.


Assuntos
Antígenos de Bactérias/imunologia , Epitopos/imunologia , Mycobacterium tuberculosis/imunologia , Mycobacterium/imunologia , Sequência de Aminoácidos , Antígenos de Bactérias/química , Proteínas de Bactérias/química , Proteínas de Bactérias/imunologia , Vacinas Bacterianas , Sequência de Bases , Biologia Computacional , Simulação por Computador , Sequência Conservada , Epitopos/química , Genoma Bacteriano , Humanos , Mycobacterium/genética , Mycobacterium tuberculosis/genética , Alinhamento de Sequência , Análise de Sequência de DNA
15.
BMC Immunol ; 14 Suppl 1: S3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23458564

RESUMO

BACKGROUND: Immunoglobulin A is the most abundant isotype in secretions from mucosal surfaces of the gastrointestinal, respiratory and genitourinary tracts and in external secretions such as colostrum, breast milk, tears and saliva. The high concentration of human secretory IgA (hsIgA) in human colostrum strongly suggests that it should play an important role in the passive immune protection against gastrointestinal and respiratory infections. MATERIALS AND METHODS: Human secretory IgA was purified from colostrum. The reactivity of hsIgA against mycobacterial antigens and its protective capacity against mycobacterial infection was evaluated. RESULTS: The passive administration of hsIgA reduces the pneumonic area before challenge with M. tuberculosis. The intratracheal administration of M. tuberculosis preincubated with hsIgA to mice greatly reduced the bacterial load in the lungs and diminished lung tissue injury. CONCLUSIONS: HsIgA purified from colostrum protects against M. tuberculosis infection in an experimental mouse model.


Assuntos
Colostro/imunologia , Imunização Passiva , Imunoglobulina A Secretora/administração & dosagem , Imunoglobulina A Secretora/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/prevenção & controle , Animais , Antígenos de Bactérias/imunologia , Carga Bacteriana , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/fisiologia , Tuberculose Pulmonar/imunologia
16.
BMC Immunol ; 14 Suppl 1: S7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23458692

RESUMO

The only currently available vaccine against tuberculosis (TB) is Mycobacterium bovis Bacille Calmette-Guerin (BCG), which has inconsistent efficacy to protect against the disease in adults. M. tuberculosis (MTB) cell wall components have been implicated in the pathogenicity of TB and therefore have been a prime target for the identification and characterization of cell wall proteins with potential application in vaccine development. In this regard, proteoliposomes (PLs) derived from mycobacteria containing lipids and cell wall proteins could be potential vaccine candidates against TB. In the present study PLs derived from BCG were prepared. These homogeneous population of spherical microparticles was then immunized into Balb/c mice. Sera of immunized animals showed high IgG response and strong cross-reactivity against different MTB antigens.These results showed that BCG PLs could be potential vaccine candidates against TB.


Assuntos
Anticorpos Antibacterianos/sangue , Vacina BCG/imunologia , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/imunologia , Proteolipídeos/imunologia , Tuberculose/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Parede Celular/imunologia , Reações Cruzadas , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Lipídeos de Membrana/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Tuberculose/prevenção & controle
17.
Artigo em Inglês | MEDLINE | ID: mdl-36674401

RESUMO

(1) Background: The assessment of vaccine effectiveness against the Omicron variant is vital in the fight against COVID-19, but research on booster vaccine efficacy using nationwide data was lacking at the time of writing. This study investigates the effectiveness of booster doses on the Omicron wave in Malaysia against COVID-19 infections and deaths; (2) Methods: This study uses nationally representative data on COVID-19 from 1 January to 31 March 2022, when the Omicron variant was predominant in Malaysia. Daily new infections, deaths, ICU utilization and Rt values were compared. A screening method was used to predict the vaccine effectiveness against COVID-19 infections, whereas logistic regression was used to estimate vaccine effectiveness against COVID-19-related deaths, with efficacy comparison between AZD1222, BNT162b2 and CoronaVac; (3) Results: Malaysia's Omicron wave started at the end of January 2022, peaking on 5 March 2022. At the time of writing, statistics for daily new deaths, ICU utilization, and effective reproductive values (Rt) were showing a downtrend. Boosted vaccination is 95.4% (95% CI: 95.4, 95.4) effective in curbing COVID-19 infection, compared to non-boosted vaccination, which is 87.2% (95% CI: 87.2, 87.2). For symptomatic infection, boosted vaccination is 97.4% (95% CI: 97.4, 97.4) effective, and a non-boosted vaccination is 90.9% (95% CI: 90.9, 90.9). Against COVID-19-related death, boosted vaccination yields a vaccine effectiveness (VE) of 91.7 (95% CI: 90.6, 92.7) and full vaccination yields a VE of 65.7% (95% CI: 61.9, 69.1). Looking into the different vaccines as boosters, AZD1222 is 95.2% (CI 95%: 92.7, 96.8) effective, BNT162b2 is 91.8% (CI 95%: 90.7, 92.8) effective and CoronaVac is 88.8% (CI 95%: 84.9, 91.7) effective against COVID-19 deaths. (4) Conclusions: Boosters are effective in increasing protection against COVID-19, including the Omicron variant. Given that the VE observed was lower, CoronaVac recipients are encouraged to take boosters due to its lower VE.


Assuntos
Vacina BNT162 , COVID-19 , Humanos , Malásia/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , SARS-CoV-2 , Vacinação
18.
Clin Dev Immunol ; 2012: 849195, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22548115

RESUMO

Given their roles in immune regulation, the expression of the nuclear receptor peroxisome proliferator-activated receptor γ (PPARγ) 1 and 2 isoforms was investigated in human naïve (CD45RA+) and memory (CD45RO+) CD4+ T cells. Stimulation of both types of cells via the CD3/CD28 pathway resulted in high expression of both PPARγ receptors as measured by real-time PCR. Treatment with the PPARγ agonist, ciglitazone, increased PPARγ1 expression but decreased PPARγ2 expression in stimulated naïve and memory cells. Furthermore, when present, the magnitude of both PPARγ receptors expression was lower in naïve cells, perhaps suggesting a lower regulatory control of these cells. Similar profiles of selected proinflammatory cytokines were expressed by the two cell types following stimulation. The induction of PPARγ1 and suppression of PPARγ2 expressions in naïve and memory CD4+ T cells in the presence of ciglitazone suggest that the PPARγ subtypes may have different roles in the regulation of T-cell function.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hipoglicemiantes/farmacologia , PPAR gama/agonistas , PPAR gama/antagonistas & inibidores , RNA Mensageiro/biossíntese , Tiazolidinedionas/farmacologia , Antígenos CD/imunologia , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica/imunologia , Humanos , Memória Imunológica , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Microesferas , PPAR gama/genética , PPAR gama/imunologia , RNA Mensageiro/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
19.
Hum Immunol ; 83(7): 564-573, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35483989

RESUMO

Next-generation DNA sequencing (NGS) technology advancements provide new insight into the level of variation in killer immunoglobulin-like receptor (KIR) genes. High resolution allele genotyping of seven KIR genes was conducted among 94 unrelated Malay and Orang Asli (OA) individuals of Peninsular Malaysia. A manual bioinformatics analysis is performed and optimised by Sanger sequencing method. The Malays expressed a total of 22 alleles, as compared to only 15 alleles in the OA population. In total, 12 centromeric and 9 telomeric allelic haplotypes were identified in the Malays, whereas 8 centromeric and 5 telomeric allelic haplotypes were identified in the OA. The KIR2DL1, KIR2DL3, and KIR2DS4 genes exhibited a high degree of variation and balanced distribution in the Malay and OA populations. On the other hand, KIR2DL4, KIR3DL1, KIR3DL2 and KIR3DL3 genes exhibited a high degree of conservation, with less number of alleles identified and the dominance of a single allele at high frequency. High-resolution KIR allele genotyping has revealed unique sequence variations and allelic haplotypes between individuals and populations. The distributions of KIR alleles and haplotypes are useful for genetic population studies and serve as a baseline for future transplantation matching and disease association research.


Assuntos
Polimorfismo Genético , Receptores KIR , Alelos , Frequência do Gene , Genótipo , Haplótipos , Humanos , Malásia , Receptores KIR/genética
20.
PeerJ ; 10: e13083, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35287350

RESUMO

Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) in late 2019, hundreds of millions of people have been infected worldwide. There have been unprecedented efforts in acquiring effective vaccines to confer protection against the disease. mRNA vaccines have emerged as promising alternatives to conventional vaccines due to their high potency with the capacity for rapid development and low manufacturing costs. In this review, we summarize the currently available vaccines against SARS-CoV-2 in development, with the focus on the concepts of mRNA vaccines, their antigen selection, delivery and optimization to increase the immunostimulatory capability of mRNA as well as its stability and translatability. We also discuss the host immune responses to the SARS-CoV-2 infection and expound in detail, the adaptive immune response upon immunization with mRNA vaccines, in which high levels of spike-specific IgG and neutralizing antibodies were detected after two-dose vaccination. mRNA vaccines have been shown to induce a robust CD8+T cell response, with a balanced CD4+ TH1/TH2 response. We further discuss the challenges and limitations of COVID-19 mRNA vaccines, where newly emerging variants of SARS-CoV-2 may render currently deployed vaccines less effective. Imbalanced and inappropriate inflammatory responses, resulting from hyper-activation of pro-inflammatory cytokines, which may lead to vaccine-associated enhanced respiratory disease (VAERD) and rare cases of myocarditis and pericarditis also are discussed.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/prevenção & controle , Vacinas de mRNA , Vacinas contra COVID-19 , Imunização , RNA Mensageiro/genética
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