ArticlePloS one2012
The density of knobs on Plasmodium falciparum-infected erythrocytes depends on developmental age and varies among isolates.
Article in PloS one, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 34 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
34 citing papers in PubMed.
- Rosette margination in blood flow during malaria pathogenesis.Biophysical journal · 2026Article
- Contact Dynamics of CytoadheringACS infectious diseases · 2025Article
- Deep learning image analysis for continuous single-cell imaging of dynamic processes in Plasmodium falciparum-infected erythrocytes.Communications biology · 2025Article
- Comparative 3D ultrastructure of Plasmodium falciparum gametocytes.Nature communications · 2025Article
- Breaking the bind: PfEMP1-specific antibodies in cerebral malaria.Frontiers in immunology · 2025Review
- Natural killer cell antibody-dependent cellular cytotoxicity toClinical & translational immunology · 2024Article
- PfEMP1 and var genes - Still of key importance in Plasmodium falciparum malaria pathogenesis and immunity.Advances in parasitology · 2024Review
- Variable Surface Antigens ofProtein and peptide letters · 2024Review
- Knobs, Adhesion, and Severe Falciparum Malaria.Tropical medicine and infectious disease · 2023Review
- CD36-A Host Receptor Necessary for Malaria Parasites to Establish and Maintain Infection.Microorganisms · 2022Review
- A particle-based computational model to analyse remodelling of the red blood cell cytoskeleton during malaria infections.PLoS computational biology · 2022Article
- Ultrastructural characterization of host-parasite interactions ofParasitology · 2022Article
- Sickle-trait hemoglobin reduces adhesion to both CD36 and EPCR by Plasmodium falciparum-infected erythrocytes.PLoS pathogens · 2021Article
- Biophysical and biomolecular interactions of malaria-infected erythrocytes in engineered human capillaries.Science advances · 2020Article
- Cerebral Plasmodium falciparum malaria: The role of PfEMP1 in its pathogenesis and immunity, and PfEMP1-based vaccines to prevent it.Immunological reviews · 2020Review
- Host Cytoskeleton Remodeling throughout the Blood Stages of Plasmodium falciparum.Microbiology and molecular biology reviews : MMBR · 2019Review
- Functional Antibodies against Placental Malaria Parasites Are Variant Dependent and Differ by Geographic Region.Infection and immunity · 2019Article
- The knob protein KAHRP assembles into a ring-shaped structure that underpins virulence complex assembly.PLoS pathogens · 2019Article
- Single-molecule imaging and quantification of the immune-variant adhesin VAR2CSA on knobs ofCommunications biology · 2019Article
- Evasion of Classical Complement Pathway Activation onFrontiers in immunology · 2018Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe virulence of Plasmodium falciparum malaria is related to the parasite's ability to evade host immunity through clonal antigenic variation and tissue-specific adhesion of infected erythrocytes (IEs). The P. falciparum erythrocyte membrane protein 1 (PfEMP1) family expressed on dome-shaped protrusions called knobs on the IE surface is central to both. Differences in receptor specificity and affinity of expressed PfEMP1 are important for IE adhesiveness, but it is not known whether differences in the number and size of the knobs on which the PfEMP1 proteins are expressed also play a role. Therefore, the aim of this study was to provide detailed information on isolate- and time-dependent differences in knob size and density. METHODOLOGY/PRINCIPAL
findingsWe used atomic force microscopy to characterize knobs on the surface of P. falciparum-infected erythrocytes. Fourteen ex vivo isolates from Ghanaian children with malaria and 10 P. falciparum isolates selected in vitro for expression of a particular PfEMP1 protein (VAR2CSA) were examined. Knob density increased from ∼20 h to ∼35 h post-invasion, with significant variation among isolates. The knob density ex vivo, which was about five-fold higher than following long-term in vitro culture, started to decline within a few months of culture. Although knob diameter and height varied among isolates, we did not observe significant time-dependent variation in these dimensions. CONCLUSIONS/SIGNIFICANCE: The density of knobs on the P. falciparum-IE surface depends on time since invasion, but is also determined by the infecting isolate in a time-independent manner. This is the first study to quantitatively evaluate knob densities and dimensions on different P. falciparum isolates, to examine ex vivo isolates from humans, and to compare ex vivo and long-term in vitro-cultured isolates. Our findings contribute to the understanding of the interaction between P. falciparum parasites and the infected host.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.