Limits...
Plasmodium falciparum merozoite surface protein 1 block 2 gene polymorphism in field isolates along the slope of mount Cameroon: a cross - sectional study.

Apinjoh TO, Tata RB, Anchang-Kimbi JK, Chi HF, Fon EM, Mugri RN, Tangoh DA, Nyingchu RV, Ghogomu SM, Nkuo-Akenji T, Achidi EA - BMC Infect. Dis. (2015)

Bottom Line: All family specific allelic types (K1, MAD20 and RO33) as well as MR were observed in the different locations, with K1 being most abundant.Eighty seven (60 %) of individuals harbored more than one parasite clone, with a significant proportion (p = 0.009) in rural compared to other settings.These results indicate enormous diversity of P. falciparum in the area and suggests that allele specificity and complexity may be relevant for the progression to symptomatic disease.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Molecular Biology, University of Buea, Buea, Cameroon. apinjohtoby@yahoo.co.uk.

ABSTRACT

Background: Malaria remains a major global health burden despite the intensification of control efforts, due partly to the lack of an effective vaccine. Information on genetic diversity in natural parasite populations constitutes a major impediment to vaccine development efforts and is limited in some endemic settings. The present study characterized diversity by investigating msp1 block 2 polymorphisms and the relationship between the allele families with ethnodemographic indices and clinical phenotype.

Method: Individuals with asymptomatic parasitaemia (AP) or uncomplicated malaria (UM) were enrolled from rural, semi-rural and semi-urban localities at varying altitudes along the slope of mount Cameroon. P. falciparum malaria parasitaemic blood screened by light microscopy was depleted of leucocytes using CF11 cellulose columns and the parasite DNA genotyped by nested PCR.

Results: Length polymorphism was assessed in 151 field isolates revealing 64 (5) and 274 (22) distinct recombinant and major msp1 allelic fragments (genotypes) respectively. All family specific allelic types (K1, MAD20 and RO33) as well as MR were observed in the different locations, with K1 being most abundant. Eighty seven (60 %) of individuals harbored more than one parasite clone, with a significant proportion (p = 0.009) in rural compared to other settings. AP individuals had higher (p = 0.007) K1 allele frequencies but lower (p = 0.003) mean multiplicity of genotypes per infection (2.00 ± 0.98 vs. 2.56 ± 1.17) compared to UM patients.

Conclusions: These results indicate enormous diversity of P. falciparum in the area and suggests that allele specificity and complexity may be relevant for the progression to symptomatic disease.

No MeSH data available.


Related in: MedlinePlus

Map of the study area. Localities on the slope of Mt. Cameroon included in the survey are indicated by blue triangles
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4526171&req=5

Fig1: Map of the study area. Localities on the slope of Mt. Cameroon included in the survey are indicated by blue triangles

Mentions: This cross-sectional community - and hospital - based study was conducted between May 2013 and March 2014. Communities were first identified as rural, semi-rural or semi-urban and then randomly selected based on differences in altitude (Fig. 1). All selected sites were geo-located using a handheld GPS (eTrex, Vista, Garmin, USA); communities below 251 m were considered to be at low altitude while those between 385 – 626 m and above 626 m were at intermediate and high altitude respectively [20]. Individuals with asexual P. falciparum infection and no signs/symptoms of the disease, asymptomatic parasitaemia (AP), were enrolled through surveys in randomly selected communities as described elsewhere [20]. Uncomplicated Malaria (UM) subjects were registered from health facilities within these communities andcharacterised by an axillary temperature ≥ 37.5 °C, asexual P. falciparum parasitaemia, haemoglobin ≥ 8 g/dL and full consciousness but noclinical signs and symptoms of severe malaria and/or evidence of vital organ dysfunction. A structured questionnaire was used to record demographic and clinical data such as age, area of residence and drug history of all participants.Fig. 1


Plasmodium falciparum merozoite surface protein 1 block 2 gene polymorphism in field isolates along the slope of mount Cameroon: a cross - sectional study.

Apinjoh TO, Tata RB, Anchang-Kimbi JK, Chi HF, Fon EM, Mugri RN, Tangoh DA, Nyingchu RV, Ghogomu SM, Nkuo-Akenji T, Achidi EA - BMC Infect. Dis. (2015)

Map of the study area. Localities on the slope of Mt. Cameroon included in the survey are indicated by blue triangles
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4526171&req=5

Fig1: Map of the study area. Localities on the slope of Mt. Cameroon included in the survey are indicated by blue triangles
Mentions: This cross-sectional community - and hospital - based study was conducted between May 2013 and March 2014. Communities were first identified as rural, semi-rural or semi-urban and then randomly selected based on differences in altitude (Fig. 1). All selected sites were geo-located using a handheld GPS (eTrex, Vista, Garmin, USA); communities below 251 m were considered to be at low altitude while those between 385 – 626 m and above 626 m were at intermediate and high altitude respectively [20]. Individuals with asexual P. falciparum infection and no signs/symptoms of the disease, asymptomatic parasitaemia (AP), were enrolled through surveys in randomly selected communities as described elsewhere [20]. Uncomplicated Malaria (UM) subjects were registered from health facilities within these communities andcharacterised by an axillary temperature ≥ 37.5 °C, asexual P. falciparum parasitaemia, haemoglobin ≥ 8 g/dL and full consciousness but noclinical signs and symptoms of severe malaria and/or evidence of vital organ dysfunction. A structured questionnaire was used to record demographic and clinical data such as age, area of residence and drug history of all participants.Fig. 1

Bottom Line: All family specific allelic types (K1, MAD20 and RO33) as well as MR were observed in the different locations, with K1 being most abundant.Eighty seven (60 %) of individuals harbored more than one parasite clone, with a significant proportion (p = 0.009) in rural compared to other settings.These results indicate enormous diversity of P. falciparum in the area and suggests that allele specificity and complexity may be relevant for the progression to symptomatic disease.

View Article: PubMed Central - PubMed

Affiliation: Department of Biochemistry and Molecular Biology, University of Buea, Buea, Cameroon. apinjohtoby@yahoo.co.uk.

ABSTRACT

Background: Malaria remains a major global health burden despite the intensification of control efforts, due partly to the lack of an effective vaccine. Information on genetic diversity in natural parasite populations constitutes a major impediment to vaccine development efforts and is limited in some endemic settings. The present study characterized diversity by investigating msp1 block 2 polymorphisms and the relationship between the allele families with ethnodemographic indices and clinical phenotype.

Method: Individuals with asymptomatic parasitaemia (AP) or uncomplicated malaria (UM) were enrolled from rural, semi-rural and semi-urban localities at varying altitudes along the slope of mount Cameroon. P. falciparum malaria parasitaemic blood screened by light microscopy was depleted of leucocytes using CF11 cellulose columns and the parasite DNA genotyped by nested PCR.

Results: Length polymorphism was assessed in 151 field isolates revealing 64 (5) and 274 (22) distinct recombinant and major msp1 allelic fragments (genotypes) respectively. All family specific allelic types (K1, MAD20 and RO33) as well as MR were observed in the different locations, with K1 being most abundant. Eighty seven (60 %) of individuals harbored more than one parasite clone, with a significant proportion (p = 0.009) in rural compared to other settings. AP individuals had higher (p = 0.007) K1 allele frequencies but lower (p = 0.003) mean multiplicity of genotypes per infection (2.00 ± 0.98 vs. 2.56 ± 1.17) compared to UM patients.

Conclusions: These results indicate enormous diversity of P. falciparum in the area and suggests that allele specificity and complexity may be relevant for the progression to symptomatic disease.

No MeSH data available.


Related in: MedlinePlus