Identification of Exported Proteins That Bind to the Erythrocyte Cytoskeleton.

proteins are exported to the erythrocyte cytoplasm to create an environment that supports parasite replication. Although hundreds of proteins are predicted to be exported through export element (PEXEL)-dependent and -independent mechanisms, the functions of exported proteins are largely uncharacterized. In this study, we used a biochemical screening approach to identify putative exported proteins that bound to inside-out vesicles prepared from erythrocytes.

Multiparametric biophysical profiling of red blood cells in malaria infection.

Biophysical separation promises label-free, less-invasive methods to manipulate the diverse properties of live cells, such as density, magnetic susceptibility, and morphological characteristics. However, some cellular changes are so minute that they are undetectable by current methods. We developed a multiparametric cell-separation approach to profile cells with simultaneously changing density and magnetic susceptibility.

Erythrocyte CD55 mediates the internalization of parasites.

Invasion of human erythrocytes by the malaria parasite is a multi-step process. Previously, a forward genetic screen for host factors identified erythrocyte CD55 as essential for invasion, but its specific role and how it interfaces with the other factors that mediate this complex process are unknown. Using CRISPR-Cas9 editing, antibody-based inhibition, and live cell imaging, here we show that CD55 is specifically required for parasite internalization.

A common polymorphism in the mechanosensitive ion channel is associated with protection from severe malaria in humans.

Malaria caused by the apicomplexan parasite has served as a strong evolutionary force throughout human history, selecting for red blood cell polymorphisms that confer innate protection against severe disease. Recently, gain-of-function mutations in the mechanosensitive ion channel were shown to ameliorate parasite growth, blood-brain barrier dysfunction, and mortality in a mouse model of malaria. In humans, the gain-of-function allele E756del is highly prevalent and enriched in Africans, raising the possibility that it is under positive selection due to malaria.

The Plasmodium falciparum MESA erythrocyte cytoskeleton-binding (MEC) motif binds to erythrocyte ankyrin.

The MESA erythrocyte cytoskeleton binding (MEC) motif is a 13-amino acid sequence found in 14 exported Plasmodium falciparum proteins. First identified in the P. falciparum Mature-parasite-infected Erythrocyte Surface Antigen (MESA), the MEC motif is sufficient to target proteins to the infected red blood cell cytoskeleton.

The Plasmodium falciparum exported protein PF3D7_0402000 binds to erythrocyte ankyrin and band 4.1.

Plasmodium falciparum extensively modifies the infected red blood cell (RBC), resulting in changes in deformability, shape and surface properties. These alterations suggest that the RBC cytoskeleton is a major target for modification during infection. However, the molecular mechanisms leading to these changes are largely unknown.

Soil transmitted helminthiasis in Kathmandu, Nepal.

A total of 200 soil samples taken from different sites and 1,504 stool samples collected from school children (n = 188) and patients (n = 1,316) visiting the health care centres in Kathmandu Valley were included in this study. Soil samples were investigated for the presence of parasitic eggs using sucrose flotation technique. Stool samples were examined by formal-ether concentration and direct smear techniques.

Intestinal parasitosis among the elderly people in Kathmandu Valley.

Present study was carried out among the elderly people (60+ years of age) from August 2005 to July 2006 in Kathmandu Valley to assess the prevalence of intestinal parasitosis in them. Stool samples were collected from 235 elderly people (122 from government elderly home, 66 from private elderly home and 47 from the households in a rural community). The samples were examined by formal ether sedimentation and Sheather's sucrose floatation followed by Kinyoun's modified Ziehl-Neelsen staining.

Microbial study of hospital environment and carrier pattern study among staff in Nepal Medical College Teaching Hospital.

The present study was done to see the microbial flora in the environment (air and surface) of Nepal Medical College Teaching Hospital and the staffs working in the hospital. Altogether 160 environmental (air n = 43, surface n = 117) samples were collected and studied from different wards. Similarly 150 samples (48 nasal swabs, 48 throat swabs and 54 hand samples) from the staffs were collected and studied following the standard microbiological protocols.