scholarly journals Biomarkers of cellular aging during a controlled human malaria infection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Aurelie Miglar ◽  
Isaie J. Reuling ◽  
Xi Zen Yap ◽  
Anna Färnert ◽  
Robert W. Sauerwein ◽  
...  

AbstractCellular aging is difficult to study in individuals with natural infection, given the diversity of symptom duration and clinical presentation, and the high interference of aging-related processes with host and environmental factors. To address this challenge, we took advantage of the controlled human malaria infection (CHMI) model. This approach allowed us to characterize the relationship among cellular aging markers prior, during and post malaria pathophysiology in humans, controlling for infection dose, individual heterogeneity, previous exposure and co-infections. We demonstrate that already low levels of Plasmodium falciparum impact cellular aging by inducing high levels of inflammation and redox-imbalance; and that cellular senescence reversed after treatment and parasite clearance. This study provides insights into the complex relationship of telomere length, cellular senescence, telomerase expression and aging-related processes during a single malaria infection.

npj Vaccines ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Andrea A. Berry ◽  
Joshua M. Obiero ◽  
Mark A. Travassos ◽  
Amed Ouattara ◽  
Drissa Coulibaly ◽  
...  

AbstractKnowledge of the Plasmodium falciparum antigens that comprise the human liver stage immunoproteome is important for pre-erythrocytic vaccine development, but, compared with the erythrocytic stage immunoproteome, more challenging to classify. Previous studies of P. falciparum antibody responses report IgG and rarely IgA responses. We assessed IgG and IgA antibody responses in adult sera collected during two controlled human malaria infection (CHMI) studies in malaria-naïve volunteers and in 1- to 6-year-old malaria-exposed Malian children on a 251 P. falciparum antigen protein microarray. IgG profiles in the two CHMI groups were equivalent and differed from Malian children. IgA profiles were robust in the CHMI groups and a subset of Malian children. We describe immunoproteome differences in naïve vs. exposed individuals and report pre-erythrocytic proteins recognized by the immune system. IgA responses detected in this study expand the list of pre-erythrocytic antigens for further characterization as potential vaccine candidates.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jona Walk ◽  
L. Charlotte J. de Bree ◽  
Wouter Graumans ◽  
Rianne Stoter ◽  
Geert-Jan van Gemert ◽  
...  

2018 ◽  
Vol 87 (3) ◽  
Author(s):  
Cysha E. Hall ◽  
Lisa M. Hagan ◽  
Elke Bergmann-Leitner ◽  
Donna M. Tosh ◽  
Jason W. Bennett ◽  
...  

ABSTRACTSeroepidemiological studies on the prevalence of antibodies to malaria antigens are primarily conducted on individuals from regions of endemicity. It is therefore difficult to accurately correlate the antibody responses to the timing and number of prior malaria infections. This study was undertaken to assess the evolution of antibodies to the dominant surface antigens ofPlasmodium vivaxandP. falciparumfollowing controlled human malaria infection (CHMI) in malaria-naive individuals. Serum samples from malaria-naive adults, collected before and after CHMI with eitherP. vivax(n= 18) orP. falciparum(n= 18), were tested for the presence of antibodies to the circumsporozoite protein (CSP) and the 42-kDa fragment of merozoite surface protein 1 (MSP-142) ofP. vivaxandP. falciparumusing an enzyme-linked immunosorbent assay (ELISA). Approximately 1 month following CHMI with eitherP. vivaxorP. falciparum, >60% of subjects seroconverted to homologous CSP and MSP-1. More than 50% of the subjects demonstrated reactivity to heterologous CSP and MSP-142, and a similar proportion of subjects remained seropositive to homologous MSP-142>5 months after CHMI. Computational analysis provides insight into the presence of cross-reactive responses. The presence of long-lived and heterologous reactivity and its functional significance, if any, need to be taken into account while evaluating malaria exposure in field settings.


2016 ◽  
Vol 7 ◽  
Author(s):  
Susanne H. Hodgson ◽  
David Llewellyn ◽  
Sarah E. Silk ◽  
Kathryn H. Milne ◽  
Sean C. Elias ◽  
...  

Author(s):  
Kirsten E Lyke ◽  
Alexandra Singer ◽  
Andrea A Berry ◽  
Sharina Reyes ◽  
Sumana Chakravarty ◽  
...  

Abstract Background A live-attenuated Plasmodium falciparum (Pf) sporozoite (SPZ) vaccine (PfSPZ Vaccine) has shown up to 100% protection against controlled human malaria infection (CHMI) using homologous parasites (same Pf strain as in the vaccine). Using a more stringent CHMI, with heterologous parasites (different Pf strain), we assessed the impact of higher PfSPZ doses, a novel multi-dose prime regimen, and a delayed vaccine boost upon vaccine efficacy. Methods Four groups of 15 healthy, malaria-naïve adults were immunized. Group (Grp) 1 received five doses of 4.5x10 5 PfSPZ (days 1, 3, 5, 7; week 16). Grps 2, 3 and 4 received three doses (weeks 0, 8, 16) with Gp 2 receiving 9.0×10 5/dose, Grp 3 receiving 18.0×10 5/dose, and Grp 4 receiving 27.0×10 5 for dose 1 and 9.0×10 5 for doses 2 and 3. VE was assessed by heterologous CHMI after 12 or 24 weeks. Volunteers not protected at 12 weeks were boosted prior to repeat CHMI at 24 weeks. Results At 12-week CHMI, 6/15 (40%) Group 1 (P=0.04), 3/15 (20%) Group 2 vs. 0/8 controls remained aparasitemic. At 24-week CHMI, 3/13 (23%) Group 3, 3/14 (21%) Group 4 vs. 0/8 controls remained aparasitemic (Groups 2-4, VE not significant). Post-boost, 9/14 (64%) vs. 0/8 controls remained aparasitemic (3/6 Group 1, P=0.025; 6/8 Group 2, P=0.002). Conclusions Four stacked, priming injections (multi-dose priming) showed 40% VE against heterologous CHMI, while dose escalation of PfSPZ using single dose priming was not significantly protective. Boosting unprotected subjects improved VE at 24 weeks to 64%.


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