1
|
Naidoo L, Arumugam T, Ramsuran V. Host Genetic Impact on Infectious Diseases among Different Ethnic Groups. ADVANCED GENETICS (HOBOKEN, N.J.) 2023; 4:2300181. [PMID: 38099246 PMCID: PMC10716055 DOI: 10.1002/ggn2.202300181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 09/11/2023] [Indexed: 12/17/2023]
Abstract
Infectious diseases such as malaria, tuberculosis (TB), human immunodeficiency virus (HIV), and the coronavirus disease of 2019 (COVID-19) are problematic globally, with high prevalence particularly in Africa, attributing to most of the death rates. There have been immense efforts toward developing effective preventative and therapeutic strategies for these pathogens globally, however, some remain uncured. Disease susceptibility and progression for malaria, TB, HIV, and COVID-19 vary among individuals and are attributed to precautionary measures, environment, host, and pathogen genetics. While studying individuals with similar attributes, it is suggested that host genetics contributes to most of an individual's susceptibility to disease. Several host genes are identified to associate with these pathogens. Interestingly, many of these genes and polymorphisms are common across diseases. This paper analyzes genes and genetic variations within host genes associated with HIV, TB, malaria, and COVID-19 among different ethnic groups. The differences in host-pathogen interaction among these groups, particularly of Caucasian and African descent, and which gene polymorphisms are prevalent in an African population that possesses protection or risk to disease are reviewed. The information in this review could potentially help develop personalized treatment that could effectively combat the high disease burden in Africa.
Collapse
Affiliation(s)
- Lisa Naidoo
- School of Laboratory Medicine and Medical SciencesCollege of Health SciencesUniversity of KwaZulu‐NatalDurban4041South Africa
| | - Thilona Arumugam
- School of Laboratory Medicine and Medical SciencesCollege of Health SciencesUniversity of KwaZulu‐NatalDurban4041South Africa
| | - Veron Ramsuran
- School of Laboratory Medicine and Medical SciencesCollege of Health SciencesUniversity of KwaZulu‐NatalDurban4041South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA)University of KwaZulu‐NatalDurban4041South Africa
| |
Collapse
|
2
|
Naing C, Wong ST, Aung HH. Toll-like receptor 9 and 4 gene polymorphisms in susceptibility and severity of malaria: a meta-analysis of genetic association studies. Malar J 2021; 20:302. [PMID: 34217314 PMCID: PMC8255014 DOI: 10.1186/s12936-021-03836-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 06/27/2021] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Malaria is still a major public health problem in sub-Saharan Africa and South-east Asia. The clinical presentations of malaria infection vary from a mild febrile illness to life-threatening severe malaria. Toll like receptors (TLRs) are postulated to be involved in the innate immune responses to malaria. Individual studies showed inconclusive findings. This study aimed to assess the role of TLR4 (D299G, T399I) and TLR9 (T1237C, T1486C) in severity or susceptibility of malaria by meta-analysis of data from eligible studies. METHODS Relevant case-control studies that assessed the association between TLR 4/9 and malaria either in susceptibility or progression were searched in health-related electronic databases. Quality of included studies was evaluated with Newcastle-Ottawa scale. Pooled analyses for specific genetic polymorphisms were done under five genetic models. Stratified analysis was done by age and geographical region (Asian countries vs non-Asian countries). RESULTS Eleven studies (2716 cases and 2376 controls) from nine endemic countries were identified. Five studies (45.4%) obtained high score in quality assessment. Overall, a significant association between TLR9 (T1486C) and severity of malaria is observed in allele model (OR: 1.26, 95% CI: 1.08-1.48, I2 = 0%) or homozygous model (OR: 1.55, 95% CI: 1.08-2.28, I2 = 0%). For TLR9 (T1237C), a significant association with severity of malaria is observed in in heterozygous model (OR:1.89, 95% CI: 1.11-3.22, I2 = 75%). On stratifications, TLR9 (T1486C) is only significantly associated with a subgroup of children of non-Asian countries under allele model (OR: 1.25, 95% CI: 1.02-1.38), while 1237 is with a subgroup of adults from Asian countries under heterozygous model (OR: 2.0, 95% CI: 1.09-3.64, I2 = 39%). Regarding the susceptibility to malaria, TLR9 (T1237C) is significantly associated only with the children group under recessive model (OR: 2.21, 95% CI: 1.06-4.57, I2=85%) and homozygous model (OR: 1.49, 95% CI: 1.09-2.0, I2 = 0%). For TLR4 (D299G, T399I), none is significantly associated with either severity of malaria or susceptibility to malaria under any genetic models. CONCLUSIONS The findings suggest that TLR 9 (T1486C and T1237C) seems to influence the progression of malaria, under certain genetic models and in specific age group of people from specific geographical region. TLR 9 (T1237C) also plays a role in susceptibility to malaria under certain genetic models and only with children of non-Asian countries. To substantiate these, future well designed studies with larger samples across endemic countries are needed.
Collapse
Affiliation(s)
- Cho Naing
- Institute for Research, Development and Innovation (IRDI), International Medical University, 5700, Kuala Lumpur, Malaysia. .,Faculty of Tropical Heath and Medicine, James Cook University, Queensland, Australia.
| | - Siew Tung Wong
- School of Medicine, International Medical University, Kuala Lumpur, Malaysia
| | - Htar Htar Aung
- School of Medicine, International Medical University, Kuala Lumpur, Malaysia
| |
Collapse
|
3
|
Mario-Vásquez JE, Naranjo-González CA, Montiel J, Zuluaga LM, Vásquez AM, Tobón-Castaño A, Bedoya G, Segura C. Association of variants in IL1B, TLR9, TREM1, IL10RA, and CD3G and Native American ancestry on malaria susceptibility in Colombian populations. INFECTION GENETICS AND EVOLUTION 2020; 87:104675. [PMID: 33316430 DOI: 10.1016/j.meegid.2020.104675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 11/19/2020] [Accepted: 12/09/2020] [Indexed: 12/24/2022]
Abstract
Host genetics is an influencing factor in the manifestation of infectious diseases. In this study, the association of mild malaria with 28 variants in 16 genes previously reported in other populations and/or close to ancestry-informative markers (AIMs) selected was evaluated in an admixed 736 Colombian population sample. Additionally, the effect of genetic ancestry on phenotype expression was explored. For this purpose, the ancestral genetic composition of Turbo and El Bagre was determined. A higher Native American ancestry trend was found in the population with lower malaria susceptibility [odds ratio (OR) = 0.416, 95% confidence interval (95% CI) = 0.234-0.740, P = 0.003]. Three AIMs presented significant associations with the disease phenotype (MID1752, MID921, and MID1586). The first two were associated with greater malaria susceptibility (D/D, OR = 2.23, 95% CI = 1.06-4.69, P = 0.032 and I/D-I/I, OR = 2.14, 95% CI = 1.18-3.87, P = 0.011, respectively), and the latter has a protective effect on the appearance of malaria (I/I, OR = 0.18, 95% CI = 0.08-0.40, P < 0.0001). After adjustment by age, sex, municipality, and genetic ancestry, genotype association analysis showed evidence of association with malaria susceptibility for variants in or near IL1B, TLR9, TREM1, IL10RA, and CD3G genes: rs1143629-IL1B (G/A-A/A, OR = 0.41, 95% CI = 0.21-0.78, P = 0.0051), rs352139-TLR9 (T/T, OR = 0.28, 95% CI = 0.11-0.72, P = 0.0053), rs352140-TLR9 (C/C, OR = 0.41, 95% CI = 0.20-0.87, P = 0.019), rs2234237-TREM1 (T/A-A/A, OR = 0.43, 95% CI = 0.23-0.79, P = 0.0056), rs4252246-IL10RA (C/A-A/A, OR = 2.11, 95% CI = 1.18-3.75, P = 0.01), and rs1561966-CD3G (A/A, OR = 0.20, 95% CI = 0.06-0.69, P = 0.0058). The results showed the participation of genes involved in immunological processes and suggested an effect of ancestral genetic composition over the traits analyzed. Compared to the paisa population (Antioquia), Turbo and El Bagre showed a strong decrease in European ancestry and an increase in African and Native American ancestries. Also, a novel association of two single nucleotide polymorphisms with malaria susceptibility was identified in this study.
Collapse
Affiliation(s)
- Jorge Eliécer Mario-Vásquez
- Grupo Genética Molecular (GENMOL), Universidad de Antioquia, Carrera 53 No. 61-30, Lab 430. Medellín, Colombia
| | | | - Jehidys Montiel
- Grupo Malaria-Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Lina M Zuluaga
- Grupo Malaria-Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Ana M Vásquez
- Grupo Malaria-Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Alberto Tobón-Castaño
- Grupo Malaria-Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia
| | - Gabriel Bedoya
- Grupo Genética Molecular (GENMOL), Universidad de Antioquia, Carrera 53 No. 61-30, Lab 430. Medellín, Colombia
| | - Cesar Segura
- Grupo Malaria-Facultad de Medicina, Universidad de Antioquia, Carrera 53 No. 61-30, Lab 610, Medellín, Colombia.
| |
Collapse
|
4
|
The Associations between Toll-Like Receptor 9 Gene Polymorphisms and Cervical Cancer Susceptibility. Mediators Inflamm 2018; 2018:9127146. [PMID: 30147445 PMCID: PMC6083594 DOI: 10.1155/2018/9127146] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 06/27/2018] [Indexed: 12/22/2022] Open
Abstract
This meta-analysis systematically reviews the association between Toll-like receptor 9 polymorphisms and the risk of cervical cancer. Case-control studies focused on the association were collected from the PubMed, Web of Science, Cochrane Library, Embase, MEDLINE, CNKI, VIP, and Wanfang databases from inception to July 2017. We screened the studies and assessed the methodological quality of the included studies and extracted data. A meta-analysis was performed using RevMan 5.3 and Stata 12.0 software. Pooled odds ratios and 95% confidence intervals were employed to evaluate the strength of the associations between Toll-like receptor 9 polymorphisms and cervical cancer risk. A total of 9 studies comprising 3331 cervical cancer patients and 4109 healthy controls met the inclusion criteria. Of these, 8 studies contained information about G2848A (rs352140) and 4 studies contained information about −1486T/C (rs187084). Our results revealed that the associations between rs187084 and cervical cancer risk in the dominant model (p = 0.002) and heterozygous model (p = 0.002) were significant, with 1.30- and 1.32-fold increases in susceptibility, respectively, compared to that in the wild-type model. However, rs352140 was not related to cervical cancer regardless of whether the subgroup analysis was conducted (p > 0.05). In conclusion, there is a significant correlation between rs187084 and cervical cancer risk with the minor C allele increasing the risk of occurrence of cervical cancer. However, rs352140 is not associated with the occurrence of cervical cancer.
Collapse
|
5
|
Influence of polymorphisms in toll-like receptors (TLRs) on malaria susceptibility in low-endemic area of the Atlantic Forest, São Paulo, Brazil. Acta Trop 2018; 182:309-316. [PMID: 29551393 DOI: 10.1016/j.actatropica.2018.03.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/26/2018] [Accepted: 03/10/2018] [Indexed: 12/17/2022]
Abstract
In low-endemic areas for malaria transmission, asymptomatic individuals play an important role as reservoirs for malarial infection. Understanding the dynamics of asymptomatic malaria is crucial for its efficient control in these regions. Genetic host factors such as Toll-like receptor (TLR) polymorphisms may play a role in the maintenance or elimination of infection. In this study, the effect of TLR polymorphisms on the susceptibility to malaria was investigated among individuals living in the Atlantic Forest of São Paulo, Southern Brazil. A hundred and ninety-five Brazilian individuals were enrolled and actively followed up for malaria for three years. Twenty-four polymorphisms in five toll-like receptor (TLR) genes were genotyped by RFLP, direct sequencing or fragment analysis. The genotypes were analyzed for the risk of malaria. Ongoing Plasmodium vivax or P. malariae infection, was identified by the positive results in PCR tests and previous P. vivax malaria, was assumed when antiplasmodial antibodies against PvMSP119 were detected by ELISA. An evaluation of genomic ancestry was conducted using biallelic ancestry informative markers and the results were used as correction in the statistical analysis. Nine SNPs and one microsatellite were found polymorphic and three variant alleles in TLR genes were associated to malaria susceptibility. The regression coefficient estimated for SNP TLR9.-1237.T/C indicated that the presence of at least one allele C increased, on average, 2.3 times the malaria odds, compared to individuals with no allele C in this SNP. However, for individuals with the same sex, age and household, the presence of at least one allele C in SNP TLR9.-1486.T/C reduced, on average, 1.9 times the malaria odds, compared to individuals with no allele C. Moreover, this allele C plus an S allele in TLR6.P249S in individuals with same sex, age and ancestry, reduced, on average, 4.4 times the malaria odds. Our findings indicate a significant association of TLR9.-1237.T/C gene polymorphism with malarial infection and contribute to a better knowledge of the role of TLRs in malaria susceptibility in an epidemiological setting different from other settings.
Collapse
|
6
|
Mahto H, Panda AK. TLR9 (rs187084) polymorphism is neither under selection pressure and nor predisposed to systemic lupus erythematosus. Lupus 2017; 27:520-521. [PMID: 28992798 DOI: 10.1177/0961203317734923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- H Mahto
- Centre for Life Sciences, Central University of Jharkhand, Jharkhand, India
| | - A K Panda
- Centre for Life Sciences, Central University of Jharkhand, Jharkhand, India
| |
Collapse
|
7
|
Dhangadamajhi G, Kar A, Rout R, Dhangadamajhi P. A meta-analysis of TLR4 and TLR9 SNPs implicated in severe malaria. Rev Soc Bras Med Trop 2017; 50:153-160. [DOI: 10.1590/0037-8682-0475-2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 02/23/2017] [Indexed: 12/12/2022] Open
|
8
|
Kar A, Panigrahi S, Tripathy S, Mohapatra MK, Tayung K, Dhangadamajhi G. Influence of common variants of TLR4 and TLR9 on clinical outcomes of Plasmodium falciparum malaria in Odisha, India. INFECTION GENETICS AND EVOLUTION 2015; 36:356-362. [DOI: 10.1016/j.meegid.2015.10.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Revised: 07/18/2015] [Accepted: 10/07/2015] [Indexed: 12/29/2022]
|
9
|
Apinjoh TO, Anchang-Kimbi JK, Njua-Yafi C, Mugri RN, Ngwai AN, Rockett KA, Mbunwe E, Besingi RN, Clark TG, Kwiatkowski DP, Achidi EA. Association of cytokine and Toll-like receptor gene polymorphisms with severe malaria in three regions of Cameroon. PLoS One 2013; 8:e81071. [PMID: 24312262 PMCID: PMC3842328 DOI: 10.1371/journal.pone.0081071] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 10/08/2013] [Indexed: 11/23/2022] Open
Abstract
P. falciparum malaria is one of the most widespread and deadliest infectious diseases in children under five years in endemic areas. The disease has been a strong force for evolutionary selection in the human genome, and uncovering the critical human genetic factors that confer resistance to the disease would provide clues to the molecular basis of protective immunity that would be invaluable for vaccine development. We investigated the effect of single nucleotide polymorphisms (SNPs) on malaria pathology in a case- control study of 1862 individuals from two major ethnic groups in three regions with intense perennial P. falciparum transmission in Cameroon. Twenty nine polymorphisms in cytokine and toll-like receptor (TLR) genes as well as the sickle cell trait (HbS) were assayed on the Sequenom iPLEX platform. Our results confirm the known protective effect of HbS against severe malaria and also reveal a protective effect of SNPs in interleukin-10 (IL10) cerebral malaria and hyperpyrexia. Furthermore, IL17RE rs708567 GA and hHbS rs334 AT individuals were associated with protection from uncomplicated malaria and anaemia respectively in this study. Meanwhile, individuals with the hHbS rs334 TT, IL10 rs3024500 AA, and IL17RD rs6780995 GA genotypes were more susceptible to severe malarial anaemia, cerebral malaria, and hyperpyrexia respectively. Taken together, our results suggest that polymorphisms in some immune response genes may have important implications for the susceptibility to severe malaria in Cameroonians. Moreover using uncomplicated malaria may allow us to identify novel pathways in the early development of the disease.
Collapse
Affiliation(s)
- Tobias O. Apinjoh
- Department of Biochemistry and Molecular Biology, University of Buea, Buea, Cameroon
- * E-mail:
| | | | - Clarisse Njua-Yafi
- Department of Animal Biology and Physiology, University of Yaounde I, Yaounde, Cameroon
| | - Regina N. Mugri
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
| | - Andre N. Ngwai
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
| | - Kirk A. Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Eric Mbunwe
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
- Diabetes Research Center, Brussels Free University, Brussels, Belgium
| | - Richard N. Besingi
- Department of Biochemistry and Molecular Biology, University of Buea, Buea, Cameroon
- Department of Oral Biology, University of Florida, Gainesville, Florida, United States of America
| | - Taane G. Clark
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Dominic P. Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
- Wellcome Trust Sanger Institute, Hinxton, United Kingdom
| | - Eric A. Achidi
- Department of Biochemistry and Molecular Biology, University of Buea, Buea, Cameroon
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
| | | |
Collapse
|
10
|
Variants in toll-like receptor 9 gene influence susceptibility to tuberculosis in a Mexican population. J Transl Med 2013; 11:220. [PMID: 24053111 PMCID: PMC3849691 DOI: 10.1186/1479-5876-11-220] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 09/13/2013] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The control of Mycobacterium tuberculosis (Mtb) infection begins with the recognition of mycobacterial structural components by toll like receptors (TLRs) and other pattern recognition receptors. Our objective was to determine the influence of TLRs polymorphisms in the susceptibility to develop tuberculosis (TB) in Amerindian individuals from a rural area of Oaxaca, Mexico with high TB incidence. METHODS We carried out a case-control association community based study, genotyping 12 polymorphisms of TLR2, TLR4, TLR6 and TLR9 genes in 90 patients with confirmed pulmonary TB and 90 unrelated exposed but asymptomatic household contacts. RESULTS We found a significant increase in the frequency of the allele A of the TLR9 gene polymorphism rs352139 (A>G) in the group of TB patients (g.f. = 0.522) when compared with controls (g.f. = 0.383), (Pcorr = 0.01, OR = 1.75). Under the recessive model (A/G + A/A vs G/G) this polymorphism was also significantly associated with TB (Pcorr = 0.01, OR= 2.37). The association of the SNP rs352139 was statistically significant after adjustment by age, gender and comorbidities by regression logistic analysis (Dominant model: p value = 0.016, OR = 2.31; Additive model: p value = 0.023, OR = 1.68). The haplotype GAA of TLR9 SNPs was also associated with TB susceptibility (Pcorr = 0.02). Differences in the genotype or allele frequencies of TLR2, TLR4 and TLR6 polymorphisms between TB patients and healthy contacts were not detected. CONCLUSIONS Our study suggests that the allele A of the intronic polymorphism rs352139 on TLR9 gene might contribute to the risk of developing TB in Mexican Amerindians.
Collapse
|
11
|
The host genetic diversity in malaria infection. J Trop Med 2012; 2012:940616. [PMID: 23316245 PMCID: PMC3532872 DOI: 10.1155/2012/940616] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2012] [Revised: 11/06/2012] [Accepted: 11/19/2012] [Indexed: 02/06/2023] Open
Abstract
Populations exposed to Plasmodium infection develop genetic mechanisms of protection against severe disease. The clinical manifestation of malaria results primarily from the lysis of infected erythrocytes and subsequent immune and inflammatory responses. Herein, we review the genetic alterations associated with erythrocytes or mediators of the immune system, which might influence malaria outcome. Moreover, polymorphisms in genes related to molecules involved in mechanisms of cytoadherence and their influence on malaria pathology are also discussed. The results of some studies have suggested that the combinatorial effects of a set of genetic factors in the erythrocyte-immunology pathway might be relevant to host resistance or susceptibility against Plasmodium infection. However, these results must be interpreted with caution because of the differences observed in the functionality and frequency of polymorphisms within different populations. With the recent advances in molecular biology techniques, more robust studies with reliable data have been reported, and the results of these studies have identified individual genetic factors for consideration in preventing severe disease and the individual response to treatment.
Collapse
|
12
|
Polymorphisms in the Fc gamma receptor IIIA and Toll-like receptor 9 are associated with protection against severe malarial anemia and changes in circulating gamma interferon levels. Infect Immun 2012; 80:4435-43. [PMID: 23045477 DOI: 10.1128/iai.00945-12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
An understanding of the immunogenetic basis of naturally acquired immunity to Plasmodium falciparum infection would aid in the designing of a rationally based malaria vaccine. Variants within the Fc gamma receptors (FcγRs) mediate immunity through engagement of immunoglobulin G and other immune mediators, such as gamma interferon (IFN-γ), resulting in erythrophagocytosis and production of inflammatory cytokines in severe malarial anemia (SMA). The Toll-like receptors (TLRs) trigger transcription of proinflammatory cytokines and induce adaptive immune responses. Therefore, these receptors may condition malaria disease pathogenesis through alteration in adaptive and innate immune responses. To further delineate the impacts of FcγRIIIA and TLR9 in SMA pathogenesis, the associations between FcγRIIIA -176F/V and TLR9 -1237T/C variants, SMA (hemoglobin [Hb] < 6.0 g/dl), and circulating IFN-γ levels were investigated in children (n = 301) from western Kenya with acute malaria. Multivariate logistic regression analysis (controlling for potential confounders) revealed that children with the FcγRIIIA -176V/TLR9 -1237C (VC) variant combination had 64% reduced odds of developing SMA (odds ratio [OR], 0.36; 95% confidence interval [CI], 0.20 to 0.64; P = 0.001), while carriers of the FcγRIIIA -176V/TLR9 -1237T (VT) variant combination were twice as susceptible to SMA (OR, 2.04; 95% CI, 1.19 to 3.50; P = 0.009). Children with SMA had higher circulating IFN-γ levels than non-SMA children (P = 0.008). Hemoglobin levels were negatively correlated with IFN-γ levels (r = -0.207, P = 0.022). Consistently, the FcγRIIIA -176V/TLR9 -1237T (VT) carriers had higher levels of circulating IFN-γ (P = 0.011) relative to noncarriers, supporting the observation that higher IFN-γ levels are associated with SMA. These results demonstrate that FcγRIIIA-176F/V and TLR9 -1237T/C variants condition susceptibility to SMA and functional changes in circulating IFN-γ levels.
Collapse
|
13
|
Sawian CE, Lourembam SD, Banerjee A, Baruah S. Polymorphisms and expression of TLR4 and 9 in malaria in two ethnic groups of Assam, northeast India. Innate Immun 2012; 19:174-83. [DOI: 10.1177/1753425912455675] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Infectious diseases have been postulated to play an important role in exerting pressure and in selection of TLR polymorphisms. Single nucelotide polymorphisms (SNPs) of TLR4 have been reported to show unique distributions in populations from Africa, Asia and Europe, and malaria is suggested to influence these patterns. In this context, we examined association of TLR polymorphisms with the risk of malaria in two ethnic groups—the Austro-Asiatics and Tibeto-Burmans—from malaria endemic districts of Assam to understand the influence of malaria in selection of TLRs in these genetically-distinct populations. TLR9 (T-1237C) mutation was positively associated with complicated ( P = 0.001) and frequent ( P = 0.035) malaria in Austro-Asiatics (relative risk = 0.595 95% CI: 0.479–0.836), but not in Tibeto-Burmans. Nonetheless, these alleles were not in Hardy-Weinberg Equilibrium in Tibeto-Burmans ( P < 0.001). In contrast, the TLR9 1486T/C genotype was favourable where it was negatively associated with complicated malaria (Fishers exact P = 0.014). Sequencing data revealed that the two populations differed in nucleotide diversity of the TLR9 promoter region. Enhanced expression of TLR4 ( P = 0.05), but not of TLR9, was associated with complicated malaria. Austro-Asiatics appeared to have accumulated favourable genotypes of TLR9, perhaps because of their longer exposure to malaria.
Collapse
Affiliation(s)
- Clara E Sawian
- Department of Molecular Biology and Biotechnology, Tezpur University, India
| | - Sonia D Lourembam
- Department of Molecular Biology and Biotechnology, Tezpur University, India
| | - Arunabha Banerjee
- Department of Molecular Biology and Biotechnology, Tezpur University, India
| | - Shashi Baruah
- Department of Molecular Biology and Biotechnology, Tezpur University, India
| |
Collapse
|
14
|
Role of polymorphisms of toll-like receptor (TLR) 4, TLR9, toll-interleukin 1 receptor domain containing adaptor protein (TIRAP) and FCGR2A genes in malaria susceptibility and severity in Burundian children. Malar J 2012; 11:196. [PMID: 22691414 PMCID: PMC3411399 DOI: 10.1186/1475-2875-11-196] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Accepted: 06/12/2012] [Indexed: 01/17/2023] Open
Abstract
Background Malaria caused by Plasmodium falciparum is one of the leading causes of human morbidity and mortality from infectious diseases, predominantly in tropical and sub-tropical countries. As genetic variations in the toll-like receptors (TLRs)-signalling pathway have been associated with either susceptibility or resistance to several infectious and inflammatory diseases, the supposition is that single nucleotide polymorphisms (SNPs) of TLR2, TLR4, TLR9, Toll-interleukin 1 receptor domain containing adaptor protein (TIRAP) and FCGR2A could modulate malaria susceptibility and severity. Methods This study was planned to make a further contribution to solving the problem of the real role of the most common polymorphisms of TLR4, TLR9, TIRAP and FCGR2A genes in modulating the risk of malaria and disease severity in children from Burundi, Central Africa. All the paediatric patients aged six months to 10 years admitted to the hospital of Kiremba, Burundi, between February 2011 and September 2011, for fever and suspicion of acute malaria were screened for malaria parasitaemia by light microscopy of thick and thin blood smears. In children with malaria and in uninfected controls enrolled during the study period in the same hospital, blood samples were obtained on filter paper and TLR4 Asp299Gly rs4986790, TLR9 G1174A rs352139, T-1486 C rs187084 TLR9 T-1237 C rs5743836, TIRAP Ser180Leu rs8177374 and the FCGR2A His131Arg rs1801274 polymorphisms were studied using an ABI PRISM 7900 HT Fast Real-time instrument. Results A total of 602 patients and 337 controls were enrolled. Among the malaria cases, 553 (91.9 %) were considered as suffering from uncomplicated and 49 (8.1 %) from severe malaria. TLR9 T1237C rs5743836CC was associated with an increased risk of developing malaria (p = 0.03), although it was found with the same frequency in uncomplicated and severe malaria cases. No other differences were found in all alleles studied and in genotype frequencies between malaria cases and uninfected controls as well as between uncomplicated and severe malaria cases. Conclusions TLR9 T1237C seems to condition susceptibility to malaria in Burundian children but not its severity, whereas none of the assessed SNPs of TLR4, TIRAP and FCGR2A seem to influence susceptibility to malaria and disease severity in this population.
Collapse
|
15
|
Omar AH, Yasunami M, Yamazaki A, Shibata H, Ofori MF, Akanmori BD, Shuaibu MN, Kikuchi M, Hirayama K. Toll-like receptor 9 (TLR9) polymorphism associated with symptomatic malaria: a cohort study. Malar J 2012; 11:168. [PMID: 22594374 PMCID: PMC3426469 DOI: 10.1186/1475-2875-11-168] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 04/12/2012] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND In areas mesoendemic for malaria transmission, symptomatic individuals play a significant role as reservoirs for malaria infection. Understanding the pathogenesis of symptomatic malaria is important in devising tools for augmenting malaria control. In this study, the effect of TLR9 polymorphisms on susceptibility to symptomatic malaria was investigated among Ghanaian children. METHODS Four hundred and twenty nine (429) healthy Ghanaian children, aged three to eleven years (3-11 years), were enrolled into a cohort study and actively followed up for symptomatic malaria for one year. Four TLR9 single nucleotide polymorphisms (SNPs) namely: rs187084 (C-1486 T), rs5743836(C-1237 T), rs352139 (G + 1174A) and rs352140 (G + 2848A) were genotyped by direct sequencing, and their attributable and relative risks for symptomatic malaria determined. TLR9 haplotypes were inferred using the PHASE software and analysed for the risk of symptomatic malaria. A luciferase assay was performed to investigate whether the TLR9 haplotypes influence TLR9 promoter activity. RESULTS The rs352139 GG genotype showed a significantly increased relative risk of 4.8 for symptomatic malaria (P = 0.0024) and a higher mean parasitaemia (P = 0.04). Conversely, the rs352140 GG genotype showed a significantly reduced relative risk of 0.34 (P = 0.048). TLR9 haplotypes analyses showed that TTAG haplotype was significantly associated with reduced relative risk of 0.2 for symptomatic malaria (P = 4×10⁻⁶) and a lower mean parasitaemia (0.007), while CTGA haplotype had an increased relative risk of 3.3 (P = 0.005). Functional luciferase reporter gene expression assay revealed that the TTA haplotype had a significantly higher promoter activity than the CCG, CTG and TCG haplotypes. CONCLUSIONS Taken together, these findings indicate a significant association of TLR9 gene polymorphisms with symptomatic malaria among Ghanaian children in Dangme-West district.
Collapse
Affiliation(s)
- Ahmeddin H Omar
- Department of Immunogenetics, Institute of Tropical Medicine-NEKKEN and Global COE Program, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Chen X, Wang S, Liu L, Chen Z, Qiang F, Kan Y, Shen Y, Wu J, Shen H, Hu Z. A genetic variant in the promoter region of Toll-like receptor 9 and cervical cancer susceptibility. DNA Cell Biol 2011; 31:766-71. [PMID: 22059466 DOI: 10.1089/dna.2011.1427] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The Toll-like receptors (TLRs) are important for the innate immune system by recognizing pathogen-associated molecular patterns expressed in infectious agents. E6 and E7 protein from HPV16 suppress the host immune response by regulating the TLR9 transcript. Therefore, we hypothesized that a single nucleotide polymorphism in TLR9 may contribute to cervical cancer. We genotyped TLR9 -1486T/C (rs187084) in a case-control study of 712 cervical cancer cases and 717 cancer-free controls in Chinese women. Logistic regression analyses showed that the rs187084 heterozygote TC was associated with a significantly increased risk of cervical cancer (adjusted OR=1.28, 95% CI=1.01-1.62), compared with the TT genotype. Although the variant homozygote was associated with a nonsignificantly increased cervical cancer risk, the TC/CC genotypes contributed to the risk of cervical cancer in the dominant genetic model (adjusted OR=1.24, 95% CI=1.01-1.53). The findings indicate that TLR9 -1486T/C (rs187084) may contribute to cervical cancer carcinogenesis.
Collapse
|
17
|
Lamb TJ, Schenk MP, Todryk SM. How do malaria parasites activate dendritic cells? Future Microbiol 2010; 5:1167-71. [PMID: 20722596 DOI: 10.2217/fmb.10.85] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Evaluation of: Wu X, Gowda NM, Kumar S, Gowda S: Protein-DNA complex is the exclusive malaria parasite component that activates dendritic cells and triggers innate immune responses. J. Immunol. 184(8), 4338-4348 (2010). Malaria parasites induce strong proinflammatory immune responses upon infection. These responses, driven largely by CD4+ Th1 cells, help the body to control malaria parasitemia. When excessive, inflammatory responses contribute to the pathology observed in malaria infection. Dendritic cells (DCs) are innate immune cells that activate Th1 cells in malaria infection via the secretion of the cytokine IL-12. It remains unclear precisely which components of malaria-infected red blood cells are responsible for activating DCs. In this study, Wu et al. set out to deconstruct malaria-infected red blood cells to determine the immunogenic components that induce production of the proinflammatory cytokines IL-12 and TNF-alpha from DCs. The authors suggest that parasite DNA complexed with protein is the main trigger for activation of DCs in malaria-infected red blood cells.
Collapse
Affiliation(s)
- Tracey J Lamb
- School of Biological Sciences, Hopkins Building, University of Reading, Whiteknights Campus, Reading RG66UB, UK.
| | | | | |
Collapse
|
18
|
Coban C, Horii T, Akira S, Ishii KJ. TLR9 and endogenous adjuvants of the whole blood-stage malaria vaccine. Expert Rev Vaccines 2010; 9:775-84. [PMID: 20624050 DOI: 10.1586/erv.10.60] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Vaccination has been a successful tool in the protection against many infectious diseases, and recent advances in biotechnology have created new techniques and strategies to produce safe and efficacious vaccines for human use. However, developing a protective vaccine against malaria has been a challenge. In this article, we focus on an old approach with some new modifications, the so-called whole-parasite vaccination strategy against blood-stage Plasmodium falciparum, the deadliest human malarial agent. In addition, we discuss recent developments in our understanding of how the endogenous adjuvant activity in the parasites, which functions via Toll-like receptor 9, acts as a double-edged sword between protective vaccination and pathological responses against malaria infection.
Collapse
Affiliation(s)
- Cevayir Coban
- Immunology Frontier Research Center, World Premier Institute for Immunology, Osaka University, Suita, Osaka 565-0871, Japan.
| | | | | | | |
Collapse
|
19
|
Kubarenko AV, Ranjan S, Rautanen A, Mills TC, Wong S, Vannberg F, Neumaier M, Bekeredjian-Ding I, Hill AVS, Ahmad-Nejad P, Weber ANR. A naturally occurring variant in human TLR9, P99L, is associated with loss of CpG oligonucleotide responsiveness. J Biol Chem 2010; 285:36486-94. [PMID: 20843814 PMCID: PMC2978577 DOI: 10.1074/jbc.m110.117200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The innate immune system employs Toll-like receptors (TLRs) for the detection of invading microorganisms based on distinct molecular patterns. For example, TLR9 is activated by microbial DNA and also by short therapeutic CpG-containing oligonucleotides (CpG-ODN). TLR9 activation leads to the production of interferons and the priming of humoral adaptive immune responses. Unfortunately, the principles of ligand recognition by TLR9 are poorly understood, and genetic variants of TLR9, which may affect its function, have not been characterized systematically on the molecular level. We therefore sought to functionally characterize reported single nucleotide polymorphisms of TLR9 in the HEK293 model system. We discovered that two variants, P99L and M400I, are associated with altered receptor function regarding NF-κB activation and cytokine induction. Our investigations show that for the most functionally impaired variant, P99L, the ability to respond to physiological and therapeutic TLR9 ligands is severely compromised. However, CpG-ODN binding is normal. CpG-ODN recognition by TLR9 thus appears to involve two separate events, CpG-ODN binding and sensing. Our studies highlight Pro-99 as a residue important for the latter process. In genotyping studies, we confirmed that both M400I (rs41308230) and P99L (rs5743844) are relatively rare variants of TLR9. Our data add rs41308230 and rs5743844 to the list of functionally important TLR variants and warrant further research into their relevance for infectious disease susceptibility or responsiveness to CpG-ODN-based therapies.
Collapse
Affiliation(s)
- Andriy V Kubarenko
- Department of Toll-like Receptors and Cancer, German Cancer Research Centre (DKFZ), 69120 Heidelberg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Coban C, Yagi M, Ohata K, Igari Y, Tsukui T, Horii T, Ishii KJ, Akira S. The malarial metabolite hemozoin and its potential use as a vaccine adjuvant. Allergol Int 2010; 59:115-24. [PMID: 20414048 DOI: 10.2332/allergolint.10-rai-0194] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Indexed: 02/03/2023] Open
Abstract
Hemozoin, a bio-crystalline substance, is a hemin detoxification by-product of malaria parasites. The role of hemozoin crystals in host immune system modulation by malaria parasites, and how they interact with the immune system has been enigmatic. Here, we summarize recent progress in our understanding of how hemozoin might be interacting with the host immune system. In particular, the potential application of hemozoin crystals as an adjuvant may provide insights into the molecular mechanisms involved in immune responses to malarial infection and provide a rationale for the design of vaccines against malaria as well as other immunological disorders such as allergies.
Collapse
Affiliation(s)
- Cevayir Coban
- Laboratory of Host Defense, Immunology Frontier Research Center, World Premier Institute for Immunology, Osaka University, Osaka, Japan.
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Sam-Agudu NA, Greene JA, Opoka RO, Kazura JW, Boivin MJ, Zimmerman PA, Riedesel MA, Bergemann TL, Schimmenti LA, John CC. TLR9 polymorphisms are associated with altered IFN-gamma levels in children with cerebral malaria. Am J Trop Med Hyg 2010; 82:548-55. [PMID: 20348497 DOI: 10.4269/ajtmh.2010.09-0467] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Toll-like receptor (TLR) polymorphisms have been associated with disease severity in malaria infection, but mechanisms for this association have not been characterized. The TLR2, 4, and 9 single nucleotide polymorphism (SNP) frequencies and serum interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) levels were assessed in Ugandan children with cerebral malaria (CM, N = 65) and uncomplicated malaria (UM, N = 52). The TLR9 C allele at -1237 and G allele at 1174 were strongly linked, and among children with CM, those with the C allele at -1237 or the G allele at 1174 had higher levels of IFN-gamma than those without these alleles (P = 0.03 and 0.008, respectively). The TLR9 SNPs were not associated with altered IFN-gamma levels in children with UM or altered TNF-alpha levels in either group. We present the first human data that TLR SNPs are associated with altered cytokine production in parasitic infection.
Collapse
|