Mitochondria of a human skeletal muscle cell line associate with the parasitophorous vacuoles of three archetypal lineages of <i>Toxoplasma gondii</i> and influence fatty acid import

<i>Toxoplasma gondii</i>, an obligate intracellular parasite, acquires host nutrients to sustain its intracellular replication. A key interaction involves host mitochondrial association (HMA) with the parasitophorous vacuole membrane, previously thought to be strain- and cell-type-dependent, and notably absent in type 2 strains in fibroblasts. Here, we report that in human skeletal muscle KD3 myotubes, all three archetypal <i>T. gondii</i> strains-including type 2-demonstrate significant HMA. This association was confirmed by mitotracker staining and transmission electron microscopy. Notably, HMA appears to correlate inversely with the parasite's uptake of exogenous ¹³C-labeled fatty acids, suggesting a competitive nutrient environment shaped by host mitochondrial proximity. These findings highlight host cell-type specificity in mitochondrial interactions and suggest that HMA may function as a modulator of nutrient acquisition in a context-dependent manner. This work revises the understanding of strain-specific HMA and underscores the complexity of host-parasite metabolic interactions in muscle tissue, a physiologically relevant niche for chronic <i>T. gondii</i> infection.