Related Experiment Video
Updated: Oct 13, 2026
Mass Isolation and In Vitro Cultivation of Intramolluscan Stages of the Human Blood Fluke Schistosoma Mansoni
Published on: January 14, 2018
[Cryopreservation of microfilariae and third-stage larvae of Brugia malayi and subsequent development in the hosts]
Abstract:
Methods are studied for the cryopreservation of microfilariae (mf) and third-stage larvae (L3) of periodic Brugia malayi. RPMI-1640 tissue culture medium containing 6% dimethyl sulfoxide (DMSO) and 15% newborn calf serum were used as cryoprotectant. The larvae survived best when specimens were frozen at the rate of -0.5 degrees C to -1.0 degrees C per minute using the vapor phase of liquid nitrogen, when the temperature reached -70 degrees C to -90 degrees C the specimens were placed directly into the liquid nitrogen (-196 degrees C). After the thawing of the mf which had been stored for 6,212 and 375 days in cryogen, 96.2% of the mf were shown to be viable and developed in Aedes togoi. It was also shown that the survival rate of L3 cryopreserved for 28-321 days was also 96.2% and that, when 107 L3 frozen for 321 days were inoculated after being thawed into one jird, one live female adult was recovered at autopsy 71 days after inoculation, its morphology being the same as the unfrozen specimens. There was no correlation between the time of cryopreservation and the survival rate of the larvae.
Insights
Cryopreservation of Brugia malayi microfilariae and larvae using a specific medium and freezing method resulted in high survival rates. Long-term storage did not impact the viability of these parasitic worms.
Area of Science:
- Veterinary Parasitology
- Tropical Medicine
- Cryobiology
Background:
- Brugia malayi is a nematode parasite causing lymphatic filariasis.
- Effective cryopreservation methods are crucial for maintaining parasite stocks for research.
Purpose of the Study:
- To establish and evaluate methods for cryopreserving microfilariae (mf) and third-stage larvae (L3) of Brugia malayi.
- To assess the long-term viability and infectivity of cryopreserved Brugia malayi stages.
Main Methods:
- Cryoprotectant solution: RPMI-1640 with 6% DMSO and 15% newborn calf serum.
- Controlled-rate freezing: -0.5 to -1.0°C/min in liquid nitrogen vapor to -70 to -90°C, then direct plunge into -196°C.
- Viability assessment of mf and L3 after thawing using Aedes togoi mosquito and jird inoculation models.
Main Results:
- High post-thaw viability (96.2%) for mf stored up to 6,212 days.
- High post-thaw survival rate (96.2%) for L3 stored for 28-321 days.
- Cryopreserved L3 successfully developed into adult female worms in jirds, maintaining normal morphology.
Conclusions:
- Cryopreservation of Brugia malayi mf and L3 is feasible with high viability and infectivity.
- No correlation was observed between cryopreservation duration and larval survival rates.
- Established methods support long-term storage of Brugia malayi for research purposes.
More Related Videos
07:00Preparing Lamellae from Vitreous Biological Samples Using a Dual-Beam Scanning Electron Microscope for Cryo-Electron Tomography
Published on: August 5, 2021
04:26Laboratory Maintenance of the Lower Dipteran Fly Bradysia (Sciara) coprophila: A New/Old Emerging Model Organism
Published on: April 19, 2024