The world's scientific and social network for malaria professionals
Subscribe to free Newsletter | 10832 malaria professionals are enjoying the free benefits of MalariaWorld today


H3K36 methylation reprograms gene expression to drive early gametocyte development in Plasmodium falciparum

April 6, 2021 - 13:51 -- Open Access
Connacher J, Josling GA, Orchard LM, Reader J, Llinás M, Birkholtz LM
Epigenetics Chromatin. 2021 Apr 1;14(1):19

The Plasmodium sexual gametocyte stages are the only transmissible form of the malaria parasite and are thus responsible for the continued transmission of the disease. Gametocytes undergo extensive functional and morphological changes from commitment to maturity, directed by an equally extensive control program. However, the processes that drive the differentiation and development of the gametocyte post-commitment, remain largely unexplored. A previous study reported enrichment of H3K36 di- and tri-methylated (H3K36me2&3) histones in early-stage gametocytes. Using chromatin immunoprecipitation followed by high-throughput sequencing, we identify a stage-specific association between these repressive histone modifications and transcriptional reprogramming that define a stage II gametocyte transition point.

Plasmodium transcription repressor AP2-O3 regulates sex-specific identity of gene expression in female gametocytes

March 9, 2021 - 15:44 -- Open Access
Li Z, Cui H, Guan J, Liu C, Yang Z, Yuan J
EMBO Rep. 2021 Mar 4:e51660

Male and female gametocytes are sexual precursor cells essential for mosquito transmission of malaria parasite. Differentiation of gametocytes into fertile gametes (known as gametogenesis) relies on the gender-specific transcription program. How the parasites establish distinct repertoires of transcription in the male and female gametocytes remains largely unknown.

Phagocytosis and activation of bone marrow‐derived macrophages by Plasmodium falciparum gametocytes

February 11, 2021 - 09:31 -- Open Access
Yolanda Corbett, Silvia Parapini, Federica Perego, Valeria Messina, Serena Delbue, Paola Misiano, Mario Falchi, Francesco Silvestrini, Donatella Taramelli, Nicoletta Basilico and Sarah D’Alessandro
Malaria Journal 2021 20:81, 10 February 2021

The innate immune response against various life cycle stages of the malaria parasite plays an important role in protection against the disease and regulation of its severity. Phagocytosis of asexual erythrocytic stages is well documented, but little and contrasting results are available about phagocytic clearance of sexual stages, the gametocytes, which are responsible for the transmission of the parasites from humans to mosquitoes. Similarly, activation of host macrophages by gametocytes has not yet been carefully addressed.

NOT Open Access | Long-lasting infectivity of Plasmodium vivax present in malarial patient blood to Anopheles aquasalis

January 16, 2021 - 08:54 -- NOT Open Access
Pereira-Silva JW, Martins-Campos KM, Sabrina Dos Reis Martins E, de Souza Menezes A, Guimarães Lacerda MV, Costa Pessoa FA, Ríos-Velásquez CM
Exp Parasitol. 2021 Jan 6:108064

Experimental studies for understanding the relationship between Plasmodium vivax and its vector hosts are difficult, because of to the lack of a long-term, in vitro continuous culture system unavailability of infected blood samples, seasonality of the disease, and the concentration of most cases in remote areas. This study evaluates the duration of the infectivity of P. vivax to Anopheles aquasalis after collecting blood from malaria-infected patients. Blood was collected from patients and stored at 4 ºC and 37 ºC. Every day, for 4 days, the blood was fed to An. aquasalis adult females, and a Giemsa-stained thick blood smear was mounted to account for sexual (gametocytes) and asexual (trophozoites and schizonts) stages and calculate parasitemia.

Increased investment in gametocytes in asymptomatic Plasmodium falciparum infections in the wet season

January 13, 2021 - 10:31 -- Open Access
Oduma CO, Ogolla S, Atieli H, Ondigo BN, Lee MC, Githeko AK, Dent AE, Kazura JW, Yan G, Koepfli C
BMC Infect Dis. 2021 Jan 9;21(1):44

Transmission stemming from asymptomatic infections is increasingly being recognized as a threat to malaria elimination. In many regions, malaria transmission is seasonal. It is not well understood whether Plasmodium falciparum modulates its investment in transmission to coincide with seasonal vector abundance.

Plasmodium falciparum gametocyte carriage in symptomatic patients shows significant association with genetically diverse infections, anaemia, and asexual stage density

January 13, 2021 - 09:59 -- Open Access
Paul Sondo, Biebo Bihoun, Halidou Tinto, et al.
Malaria Journal 2021 20:31, 7 January 2021

Multi-genotype malaria infections are frequent in endemic area, and people commonly harbour several genetically distinct Plasmodium falciparum variants. The influence of genetic multiplicity and whether some specific genetic variants are more or less likely to invest into gametocyte production is not clearly understood. This study explored host and parasite-related risk factors for gametocyte carriage, and the extent to which some specific P. falciparum genetic variants are associated with gametocyte carriage.

Single-nucleotide polymorphism characterization of gametocyte development 1 gene in Plasmodium falciparum isolates from Baringo, Uasin Gishu, and Nandi Counties, Kenya

March 17, 2020 - 15:12 -- Open Access
Bungei JK, Mobegi VA, Nyanjom SG
Heliyon. 2020 Mar 3; 6(3):e03453

Plasmodium falciparum relies on gametocytogenesis to transmit from humans to mosquitoes. Gametocyte development 1 (Pfgdv1) is an upstream activator and epigenetic controller of gametocytogenesis. The emergence of drug resistance is a major public health concern and this requires the development of new strategies that target the transmission of malaria. As a putative drug target, Pfgdv1 has not been characterized to identify its polymorphisms and alleles under selection and how such polymorphisms influence protein structure.

Optimal timing of primaquine to reduce Plasmodium falciparum gametocyte carriage when co-administered with artemether–lumefantrine

January 24, 2020 - 14:49 -- Open Access
Seif Shekalaghe, Dominic Mosha, Ali Hamad, Thabit A. Mbaga, Michael Mihayo, Teun Bousema, Chris Drakeley and Salim Abdulla
Malaria Journal 2020 19:34, 21 January 2020

Primaquine is an important gametocytocidal drug that is combined with conventional malaria treatment for prevention of Plasmodium falciparum malaria transmission. Primaquine has been administered together on the first or the last day of conventional treatment but the impact of primaquine timing has never been examined. This study aimed to assess safety, efficacy and optimal timing of single full-dose (0.75 mg/kg) primaquine when added to a standard 6-dose regimen of artemether–lumefantrine (AL).

Gametocyte clearance in children, from western Kenya, with uncomplicated Plasmodium falciparum malaria after artemether-lumefantrine or dihydroartemisinin-piperaquine treatment

December 10, 2019 - 08:22 -- Open Access
Omondi P, Burugu M, Matoke-Muhia D, Too E, Nambati EA, Chege W, Musyoka KB, Thiongo K, Otinga M, Muregi F, Kimani F.
Malar J. 2019 Dec 4; 18(1):398

The efficacy and safety of artemether–lumefantrine (AL) and dihydroartemisinin–piperaquine (DP) against asexual parasites population has been documented. However, the effect of these anti-malarials on sexual parasites is still less clear. Gametocyte clearance following treatment is essential for malaria control and elimination efforts; therefore, the study sought to determine trends in gametocyte clearance after AL or DP treatment in children from a malaria-endemic site in Kenya.

NOT Open Access |Recent advances in transmission-blocking drugs for malaria elimination

December 2, 2019 - 15:10 -- NOT Open Access
Wadi I, Nath M, Anvikar AR, Singh P, Sinha A.
Future Med Chem. 2019 Nov 29.

The scientific community worldwide has realized that malaria elimination will not be possible without development of safe and effective transmission-blocking interventions. Primaquine, the only WHO recommended transmission-blocking drug, is not extensively utilized because of the toxicity issues in G6PD deficient individuals.


Subscribe to RSS - gametocyte