Maintaining phagosome integrity during fungal infection: do or die?
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Professional phagocytes represent a critical node in innate immunity and tissue homeostasis through their specialized ability to eat, drink, and digest material from the extracellular milieu. The degradative and microbicidal functions of phagocytes rely on the fusion of lysosomes with endosomal compartments such as phagosomes, resulting in the digestion and recycling of internalized prey and debris. Despite these efforts, several particularly dangerous infections result from a class of tenacious pathogens that resist digestion, often surviving and even proliferating within the confines of the phagosomal membrane. One such example, Candida albicans, is a commensal polymorphic fungus that colonizes ~50% of the population and can cause life-threatening infections in immunocompromised patients. Not only can C. albicans survive within phagosomes, but its ingestion by macropahges triggers a yeast-to-hyphal transition promoting rapid intraphagosomal growth (several microns per hour) while imposing a substantial mechanical burden on the phagosomal membrane surrounding the fungus. Preservation of membrane integrity is essential to maintain the hostile internal environment of the phagosome, a functionality of degradative enzymes and oxidative stress. Yet, biological membranes such as phagosomes have a limited capacity to stretch. Using C. albicans as a model intracellular pathogen, our recent work reveals a mechanism by which phagosomes respond to intraphagosomal growth of pathogens by expanding their surface area, and as a result, maintain the integrity of the phagosomal membrane. We hypothesized that this expansion would be facilitated by the delivery and fusion of membrane from extraneous sources with the phagosome. Consistently, macrophages respond to the yeast-to-hyphal transition through a stretch-induced release of phagosomal calcium, leading to recruitment and insertion of lysosomes that accommodate the expansion of the phagolysosome and preserve its integrity. Below, we discuss this calcium-dependent mechanism of lysosome insertion as a means of avoiding phagosomal rupture. Further, we examine the implications of membrane integrity on the delicate balance between the host and pathogen by focusing on fungal stress responses, nutrient acquisition, inflammasome activation, and cell death.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.005 |
| Insufficient payload (model declined to judge) | 0.002 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it