Sequential expression of antigens on sexual stages of Plasmodium falciparum accessible to transmission-blocking antibodies in the mosquito.

Vermeulen, A.N.; Ponnudurai, T.; Beckers, Pascal; Verhave, J.P.; Smits, M.A.; Meuwissen, J. H. E. T.

doi:10.1084/jem.162.5.1460

Cited by 326 publications

(278 citation statements)

References 35 publications

Supporting

Mentioning

271

Contrasting

Order By: Relevance

“…As an additional specificity control, we performed this binding assay with Pfs25, a protein found on the surface of zygotes and ookinetes [15]. As shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

Anopheles stephensi salivary glands bear receptors for region I of the circumsporozoite protein of Plasmodium falciparum

Sidjanski

Vanderberg

Sinnis

1997

Molecular and Biochemical Parasitology

View full text Add to dashboard Cite

In the mosquito, Plasmodium sporozoites rupture from oocysts found on the midgut wall, circulate in the hemolymph and invade salivary glands where they wait to be injected into a vertebrate host during a bloodmeal. The mechanisms by which sporozoites specifically attach to and invade salivary glands are not known but evidence suggests that it is a receptor-mediated process. Here we show that the major surface protein of sporozoites, the circumsporozoite protein (CS), binds preferentially to salivary glands when compared to other organs exposed to the circulating hemolymph. In addition, we show that a peptide encompassing region I, a highly conserved sequence found in all rodent and primate Plasmodium CS proteins, inhibits binding of CS to mosquito salivary glands.

show abstract

“…As an additional specificity control, we performed this binding assay with Pfs25, a protein found on the surface of zygotes and ookinetes [15]. As shown in Fig.…”

Section: Resultsmentioning

confidence: 99%

Anopheles stephensi salivary glands bear receptors for region I of the circumsporozoite protein of Plasmodium falciparum

Sidjanski

Vanderberg

Sinnis

1997

Molecular and Biochemical Parasitology

View full text Add to dashboard Cite

show abstract

“…15% to 80% of RF failed to develop into OOK, with an important heterogeneity among gametocyte carriers. The loss in transition from RF to OOK may be brought about by several biological mechanisms that are active in the mosquito blood meal, such as: antibodies against sexual stages (Rener et al 1980;Carter et al 1984;Vermeulen et al 1985), complement (Grotendorst & Carter 1987), cytokines (Naotunne et al1991), and phagocytosis (Sinden & Smalley 1976). These mechanisms are more or less important according to host immune state and might explain the extreme heterogeneity among gametocyte carriers (Mulder et al 1994).…”

Section: Discussionmentioning

confidence: 99%

“…These morphological changes are accompanied by the disappearance and appearance of different surface antigens including Pfs25 (Vermeulen et al 1985;Kumar & Carter 1985;Alano 1991). This newly formed protein expressed at 3 h postfeeding, persists on zygotes (3-5 h post-infection) and ookinetes (18-30 h) until young oocysts appear (36-48 h and even longer) (Lensen et al 1992).…”

Section: Introductionmentioning

confidence: 99%

The early sporogonic cycle of Plasmodium falciparum in laboratory‐infected Anopheles gambiae: an estimation of parasite efficacy

Gouagna

Mulder

Noubissi

et al. 1998

Tropical Med Int Health

View full text Add to dashboard Cite

SummaryThis study investigated the successive losses in the parasite densities of Plasmodium falciparum stages during the early sporogony in laboratory-reared Anopheles gambiae infected by membrane feeding with blood from naturally infected gametocyte carriers (Ͼ50 gametocytes/mm 3 ). The developmental stages of P. falciparum in the mosquito were studied from zygote to oocyst, by immunofluorescent method using monoclonal antibodies against the Pfs25 protein present on the surface of newly formed gametes. This method allows for assessment of the various sporogonic stages before, during and after passage of the midgut wall. Parasite densities were determined within the entire blood meal at 3 h (zygotes and macrogametes) and 24 h (ookinetes) post-infection. At 48 h after the mosquito blood meal, midguts were checked for the presence of early oocysts. For the mid-size oocysts count, classic microscopy examination was used at day 7 postinfection. The parasite efficacy was estimated by following successive losses in parasite densities between different early stages of the sporogonic cycle in A. gambiae. Thirty-seven experimental infections were realized with high gametocyte densities, ranging from 64 to 2392 gametocytes/mm 3 . All gametocyte carriers showed infection with round forms 100%; ookinetes were found in 91.9%. The prevalences of infections with oocysts were 48.6% at day 2 (young oocyst) and 37.8% at day 7 (mid-size oocyst). The mean densities per mosquito for each parasite stage were 12.6 round forms, 5.5 ookinetes, 1.8 young oocyst and 2 mid-size oocysts. Significant correlations were found between two consecutive parasite stages (round forms/ookinetes, ookinetes/young oocysts, young oocysts/mid-size oocysts) and between round forms and mid-size oocysts. The mean parasite density significantly decreased between round forms and ookinetes (yield Y1 ϭ 41.6%) and between ookinetes and young oocysts (Y2 ϭ 61.4%). By contrast, no significant decrease was observed between young oocysts and mid-size oocysts (Y3 ϭ 91.2%). The overall yield of the early sporogonic cycle (from round form to oocyst at day 7) was equal to 25.7%, indicating that almost 3/4 of the total parasites were lost during the early step of the sporogonic cycle, from 3 h post-infection to day 7.

show abstract

“…After 14 days of culture parasites were pelleted, mixed with fetal calf serum and incubated for 1 h at room temper ature to allow activation of gametogenesis and the release of gametes. Subsequently, noil-activated gametocytes and macrogametes were separated by Nycodenz density gradient centrifugation [13,14] …”

Section: î Parasitesmentioning

confidence: 99%

Developmentally regulated expression of pfs16, a marker for sexual differentiation of the human malaria parasite Plasmodium falciparum

Dechering

Thompson

Dodemont

et al. 1997

Molecular and Biochemical Parasitology

View full text Add to dashboard Cite

Abstract•Sexual differentiation is essential for the transmission of Plasmodium to mosquitoes and therefore, for the spread of malaria. The molecular mechanisms underlying sexual differentiation ar$ poorly understood but may be elucidated by a detailed study of the regulation of expression of sexual stage specific genes. In the present work we describe the differential expression of the gene encoding the sexual stage specific protein, Pfsl6. We have conducted a comparative analysis of pfs 16 promoter activity, RNA levels and the rate of de novo protein synthesis during development of Plasmodium falciparum. Furthermore, we have determined the pattern of expression of pfs 16 transcripts at the single cell level by in situ hybridisation. We show that the expression of pfs 16 is induced immediately following the invasion of a red blood cell in sexually committed ring stage parasites and continues throughout gametocytogenesis and in macrogametes. The expression of pfs 16 is regulated at the level of transcription initiation and modulated by a post-transcriptional process. These results demonstrate that the expression of thep f s l 6 gene is the earliest event in the sexual differentiation process of P. falciparum described to date. © 1997 Elsevier Science B.V.

show abstract

Sequential expression of antigens on sexual stages of Plasmodium falciparum accessible to transmission-blocking antibodies in the mosquito.

Cited by 326 publications

References 35 publications

Anopheles stephensi salivary glands bear receptors for region I of the circumsporozoite protein of Plasmodium falciparum

Anopheles stephensi salivary glands bear receptors for region I of the circumsporozoite protein of Plasmodium falciparum

The early sporogonic cycle of Plasmodium falciparum in laboratory‐infected Anopheles gambiae: an estimation of parasite efficacy

Developmentally regulated expression of pfs16, a marker for sexual differentiation of the human malaria parasite Plasmodium falciparum

Contact Info

Product

Resources

About