Michael Delves
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mjdelves.bsky.social
Michael Delves
@mjdelves.bsky.social
620 followers 540 following 34 posts
Associate Prof @ LSHTM/Co-Director of LSHTM Malaria Centre @lshtm-malaria.bsky.social/Malaria cell biology and mosquito transmission/DM me for collaboration and culture protocols.
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mjdelves.bsky.social
Looking forward to joining @lshtm-malaria.bsky.social’s #WorldMalariaDay event to reflect on what’s next for malaria research and how we can continue to drive change.
Details here www.lshtm.ac.uk/newsevents/e... | LSHTM
#Malaria #GlobalHealth #WorldMalariaDay
Invitiation to attend "Prioritising in a crisis: What next for malaria research?" Friday 25th April 12.30 BST https://www.lshtm.ac.uk/newsevents/events/prioritising-crisis-what-next-malaria-research
April 9, 2025 at 1:58 PM
mjdelves.bsky.social
The LSHTM Malaria Centre has now joined Bluesky! Please follow us and get our latest updates, research highlights, and opportunities: @lshtm-malaria.bsky.social
LSHTM Malaria Centre logo
December 3, 2024 at 11:09 AM
mjdelves.bsky.social
🆕 Our latest LSHTM Malaria Centre Report is out! 🌍

🦟 Explore the key achievements, research highlights, and ongoing collaborations from our team in the fight against malaria.

Read the full report here👉 bit.ly/3Oq7ScT

#MalariaResearch #GlobalHealth #MalariaReport @lshtm.bsky.social
LSHTM Malaria Centre Report 2022-2024
December 2, 2024 at 12:58 PM
mjdelves.bsky.social
...and a few retorts too.
Giemsa stained slide showing a Pf ookinete and two retort stages.
November 22, 2024 at 10:02 PM
mjdelves.bsky.social
Our first attempt at enriching Pf ookinetes direct from mosquito bloodmeals - low abundance, but definitely successful! (just don't look at all the bacteria that came too!)
Giemsa-stained slide showing a P. falciparum ookinete in the centre.
November 22, 2024 at 10:00 PM
mjdelves.bsky.social
Being able to confidently discriminate between male and female gametocytes allowed us to compare their mitochondrial activity using MitoTracker CMXros accumulation as a proxy. We find males consistently accumulate ~40% less than females whilst being approximately the same size and shape.
Contrasting the differences between mitochondrial organisation of male and female gametocytes using quantitative imaging. A Anti-LDH2 (green) was used to discriminate between male (LDH2-positive) and female (LDH2-negative) gametocytes co-labelled with MitoTrackerTM CMXRos (magenta) and DAPI (blue). Scale bar = 3 µM. B The same dataset used to study gametocyte nuclear morphology was reanalysed similarly using MitoTracker staining to generate mitochondrial ROIs for each cell. A variety of mitochondrial parameters were calculated and compared between populations of male and female gametocytes. n = 4 independent experiments of 133, 111, 48, and 147 gametocytes measured. Unpaired Student’s T-test: ns
November 18, 2024 at 9:45 AM
mjdelves.bsky.social
We also generated an antibody against PfLD2 (PF3D7_1325200), which is highly specific for stageIV/V male gametocytes and male gametes - raised in rat so that it can be paired with lots of other antibodies and works at 1:10,000 dilution so super-cost effective.
Anti-LDH2 is a specific marker for P. falciparum male gametocytes and gametes. A Immunostaining with anti-LDH2 (magenta) showed specific staining of a subpopulation of Pfs230-positive (green) stage IV and stage V gametocytes. B Male gametes stained with anti-alpha tubulin II (green) also were LDH2-positive, whilst Pfs25-positive (green) female gametes were LDH2-negative. Merged images also show DAPI (blue). Scale bars = 5 µM
November 18, 2024 at 9:45 AM
mjdelves.bsky.social
However, inhibiting mitochondrial ATP synthesis causes male gametocytes to abort gametogenesis - glycolysis alone cannot meet the energy demands of rapid cellular remodelling and so males *have* to invest effort in mitochondrial expansion in preparation for this single transmission event.
The quantitative and morphological differences in gametogenesis in the presence of mitochondrial inhibitor oligomycin A. A Gametogenesis was triggered in ookinete medium containing 0.1% human serum, with (2 g/L “Glucose”) or without glucose (“No glucose”), or glucose and 5 µM oligomycin A (“Glucose + OA”). Exflagellation was counted 20 min later using automated microscopy to capture exflagellation centres and automated image analysis for quantification. Data presented here is the mean of five independent experiments normalised to the exflagellation activity of the “Glucose” sample for each replicate. However statistical comparison (Ratio paired t-test) was performed before normalisation and showed that the difference in activity between “Glucose” and “Glucose + OA” samples is statistically significant (p = 0.007. n = 5. df = 4). Error bars denote standard error of the mean. BParallel samples of the cells were fixed 20 min post induction of gametogenesis and stained with anti-alpha tubulin and DAPI to visualise microtubule and DNA morphology. Bar = 5 µm.
November 18, 2024 at 9:44 AM
mjdelves.bsky.social
Using a genetically encoded ATP sensor we show that gametocytes are quite happy maintaining cytoplasmic ATP levels with glycolysis alone, so presumably mitochondrial ATP is not necessary when they are dormant in the human host.
Ratiometric measurement of cytoplasmic ATP using a FRET-based sensor ATeam1.03YEMK. Gametocytes were washed in culture medium three times with or without glucose and with or without 5 µM oligomycin A. Finally, gametocytes were then pelleted in phosphate buffered saline (PBS) containing matched glucose/ oligomycin A conditions and imaged over time at 37 °C. Imaging commenced at 3 min post treatment to account for processing time and time taken for cells to settle onto the slide for imaging. Dotted line indicates the FRET value recorded for gametocytes incubated in PBS alone for 120 min. Closed orange circles indicate gametocytes incubated with 2 g/L glucose; open orange circles indicate gametocytes incubated without glucose. Closed and open blue circles indicate gametocytes incubated with and without glucose respectively in the presence of 5 µM oligomycin A. Data represents the mean of 6–9 independent replicates performed pairwise with all possible combinations of treatment. Error bars denote the standard error of the mean (SEM).
November 18, 2024 at 9:44 AM