Wood Ear Immunity
TLR4 receptor
Auricularia auricula polysaccharides activate resting macrophages through Toll-like receptor 4 — and dampen already-activated ones. The direction of effect depends on the state of the cell, and all of it is preclinical.
Perera et al., Chemical Communications, 2018; Perera et al., Int J Biol Macromol, 2020
Both directions
activates resting macrophages, suppresses LPS-activated ones
1 of 8 studies
used the oral route people actually use
0 human trials
no immune outcome measured in people at any dose
Perera et al., Chemical Communications, 2018; Perera et al., Int J Biol Macromol, 2020
View as image ↗Wood ear mushroom (Auricularia auricula-judae) has been eaten across East Asia for centuries, but its polysaccharides do something in the lab that a food rarely does: they bind a specific immune receptor. Perera et al. (2018) established the repeating unit structure of an immunologically active glucuronoxylomannan from wood ear and identified Toll-like receptor 4 (TLR4) as a critical receptor in the macrophage activation it produces. Both the carboxylic and the acetyl groups on the polysaccharide proved equally essential for that binding.[1] That finding gave the field a mechanism where before there was only observation.
What happened next is the part that rarely survives into supplement copy. When the same group tested the same molecule on macrophages that had already been activated by bacterial endotoxin, it pushed the cells in the opposite direction — lowering nitric oxide, IL-6 and TNF-alpha rather than raising them.[2] Auricularia polysaccharides are better described as context-dependent immune modulators than as immune boosters.
All of this work is preclinical. No randomized controlled trial has tested Auricularia polysaccharides for any immune outcome in humans. For the broader context of wood ear's immune effects, see Wood Ear and the immune system: immunomodulatory research.
Key Takeaways
- Glucuronoxylomannan from Auricularia auricula-judae activates macrophages through TLR4, with carboxylic and acetyl moieties equally essential for receptor binding (Perera et al., 2018)
- The same molecule reverses direction in already-activated cells: in LPS-stimulated macrophages it downregulated nitric oxide, IL-6 and TNF-alpha via reduced NF-κB activation, an effect the authors call endotoxin-tolerance-like (Perera et al., 2020)
- Auricularia polysaccharide fraction AAP1 stimulated IFN-gamma, IL-2, IL-4, IL-10 and TNF-alpha in cyclophosphamide-immunosuppressed mice and restored gut microbiota toward control composition (Kong et al., 2020), a model independently repeated in 2025 (Zhao M. et al., 2025)
- Crude polysaccharides from Auricularia polytricha polarized human THP-1-derived macrophages to an M1 phenotype through NF-κB activation, with potency tracking the beta-glucan content of the extract (Nilkhet et al., 2024)
- In DSS colitis mice, oral Auricularia polysaccharide protection was transmissible by horizontal feces transfer, pointing to gut microbiota as an intermediary rather than direct immune-cell contact (Zhao D. et al., 2020)
- The four best-characterized preparations are structurally different molecules — a mannan-backbone glucuronoxylomannan, a mannose- and glucose-dominated fraction labelled a galactan, a beta-1,3-linked polymer, and an uncharacterized crude extract
- Zero human trials have measured immune activation from Auricularia polysaccharides in any population
The TLR4 mechanism: how Auricularia polysaccharides talk to immune cells
Macrophages carry pattern recognition receptors on their surface, proteins that evolved to detect molecular signatures of pathogens. TLR4 is one of the most studied. When a ligand binds TLR4, the receptor triggers an intracellular signaling cascade that culminates in cytokine production, phagocytosis enhancement, and antigen presentation.
Perera et al. (2018) isolated a glucuronoxylomannan polysaccharide (AAPS) from Auricularia auricula-judae, established its comprehensive repeating unit structure, and identified TLR4 as a critical receptor for the macrophage activation it induced.[1] The team combined molecular modeling with chemical modification of AAPS to show that the carboxylic and acetyl moieties are equally essential for TLR4 binding — removing either one cost the polysaccharide its in vitro immunostimulatory activity.
This structural specificity distinguishes Auricularia polysaccharides from generic "immune-boosting" claims. The effect is not a vague stimulation of the immune system. It is a defined ligand-receptor interaction with downstream signaling consequences that can be measured. TLR4 is the same receptor that recognizes bacterial lipopolysaccharide (LPS), and AAPS appears to engage it through analogous structural features.
That similarity to LPS is also the reason the story does not end with activation.
The same receptor, the opposite direction
Perera et al. returned to AAPS in 2020 to work out what happens downstream of the TLR4 binding.[2] In resting macrophages the picture extended the earlier finding: AAPS markedly increased phagocytosis and bactericidal activity, with signaling running through reactive oxygen species, MAP kinases, protein kinase C-alpha and NF-κB.
In LPS-activated macrophages, the same compound did the reverse. AAPS downregulated nitric oxide, interleukin-6 and TNF-alpha — the authors characterize this as an endotoxin-tolerance-like effect, mediated through downregulation of the same NF-κB node that drives the activating arm.[2]
Same Molecule, Opposite Directions
What AAPS Does Depends on What the Macrophage Was Already Doing
One characterised polysaccharide. One receptor. Two opposite outcomes, reported by the same laboratory. Popular summaries of wood ear immunity almost always quote the left-hand column and never the right.
Resting macrophage
[1][2]No prior inflammatory stimulus
AAPS activates
- Pro-inflammatory cytokine secretion increased
- Phagocytosis increased
- Bactericidal activity increased
TLR4 binding — requires both carboxylic and acetyl moieties on the polysaccharide. Downstream signalling runs through ROS, MAPK, PKC-alpha and NF-kB.
LPS-activated macrophage
[2]Already stimulated by bacterial endotoxin
AAPS suppresses
- Nitric oxide decreased
- Interleukin-6 decreased
- TNF-alpha decreased
The authors characterise this as an "endotoxin tolerance like effect", mediated by downregulation of NF-kB activation — the same node that drives the activating arm.
Why this matters for the word “booster”: a compound that raises cytokines in quiet cells and lowers them in inflamed cells is behaving as a modulator, not a stimulant. Both arms are in vitro, so neither settles what happens in a person. But the existence of the suppressive arm means that any claim of the form “wood ear polysaccharides boost immune activity” is quoting half of a two-sided result from a single research group.
Readouts and signalling nodes read from Perera et al. 2018 [1] and Perera et al. 2020 [2]
Two caveats belong with this result. Both arms are in vitro, so neither establishes what happens in a living animal, let alone a person. And both come from the same laboratory working on the same isolate, so the bidirectional behavior has not been independently replicated. What it does establish is that the direction of effect is a variable, not a constant — which makes any unqualified claim that wood ear "boosts" immune function a selective reading of a two-sided finding.
For comparison with how other mushroom species engage TLR signaling, see Agaricus blazei polysaccharide complex and toll-like receptor activation.
Fact Check
Myth vs. evidence
The claim
“Wood ear polysaccharides boost your immune system.”
Extrapolated from the in vitro finding that Auricularia glucuronoxylomannan activates resting macrophages through TLR4.
What research shows
Context DependentIn resting macrophages the polysaccharide raises cytokines and phagocytosis. In macrophages already activated by bacterial endotoxin, the same molecule lowers nitric oxide, IL-6 and TNF-alpha. Both results come from the same group, on the same isolate.
A compound whose effect flips sign depending on the state of the target cell is a modulator, not a stimulant. Neither arm has been tested in humans, and no study has shown that either direction is reachable by eating the mushroom.
Perera et al., Chemical Communications, 2018; Perera et al., International Journal of Biological Macromolecules, 2020
Macrophage activation: from receptor binding to cytokine production
A purified fraction promotes phagocytosis — and a naming problem
Bao et al. (2020) extracted Auricularia auricula polysaccharide by hot water, obtained three fractions, and found that only the third was a pure polysaccharide rather than a glycoprotein.[3] They renamed that fraction AAP and characterized it as a homogeneous galactan of approximately 23.51 kDa.
In RAW264.7 macrophages, AAP promoted cell proliferation, enhanced phagocytic activity, and stimulated nitric oxide production — standard markers of macrophage activation.[3]
The label deserves scrutiny. The paper reports AAP's monosaccharide molar ratio as mannose 5.02, rhamnose 0.9, gluconic acid 0.12, glucose 4.48, galactose 0.37, arabinose 1.0 and fucose 0.36. Galactose is the fifth most abundant of seven sugars in a polymer named after galactose. The methylation analysis points the same way, reporting mainly 1,4-linked and 1,4,6-linked glucose along with 1,4-linked and 1,2,6-linked mannose. Whatever AAP is, its composition and linkage profile are dominated by glucose and mannose.
There is also a model limitation. RAW264.7 is an immortalized cell line derived from a mouse leukemia. While widely used in immunology research, these cells do not faithfully represent primary tissue-resident macrophages or human macrophages. For a focused analysis of how Auricularia polysaccharides enhance phagocytic engulfment specifically, see Auricularia polysaccharides and macrophage phagocytosis enhancement.
M1 polarization in a human cell model
Macrophages exist on a spectrum between M1 (pro-inflammatory, anti-tumor) and M2 (anti-inflammatory, pro-healing) phenotypes.
Nilkhet et al. (2024) tested extracts of Auricularia polytricha — cloud ear, a close relative of A. auricula-judae — on macrophages differentiated from THP-1 cells, a human monocytic line.[4]
Nilkhet et al. (2024) · Scientific Reports
- Population
- Macrophages differentiated from THP-1, a human monocytic cell line
- Intervention
- Auricularia polytricha water extract (APW) and crude polysaccharides (APW-CP)
- Comparator
- Undifferentiated M0 macrophages
- Finding
- Both preparations significantly upregulated M1-related genes and IL-6, IL-1beta and TNF-alpha production, and raised CD86 expression versus M0. NF-κB induction was dose-dependent and related to the beta-glucan content of the extracts. APW-CP-polarized macrophages then inhibited invasion and induced apoptosis in MCF-7 and MDA-MB-231 breast cancer cells.
preliminary A human-derived cell line is a stronger model than a mouse leukemia line, but this remains cell culture with a crude, structurally uncharacterized extract. The anti-tumor effect was indirect — the polysaccharides did not kill cancer cells, the macrophages they polarized did.
Nilkhet et al., Scientific Reports, 2024
The use of a human line matters for how far the finding reaches. Bao's RAW264.7 result and Nilkhet's THP-1 result are often quoted side by side as though they carry equal weight for human physiology; they do not. It is also worth being precise about what "beta-glucan drove the effect" means here. Potency correlated with the beta-glucan content of the preparations. That is an association across extracts, not identification of the active molecule, and no structure was solved.
One Name, Four Molecules
The Field Does Not Agree on What the Active Polymer Is
Every study below is cited as evidence for “Auricularia polysaccharide” immune activity. Each one tested a structurally different preparation. A mannan-backbone glucuronoxylomannan and a beta-glucan are not the same class of molecule.
Perera et al. 2018 / 2020
[1][2]- Called it
- Glucuronoxylomannan (AAPS)
- Polymer class actually described
- Mannan backbone + glucuronic acid + xylose
The only fraction here with both a solved structure and an identified receptor (TLR4). Activity requires carboxylic and acetyl moieties.
Bao et al. 2020
[3]- Called it
- "A homogeneous galactan" (AAP), ~23.51 kDa
- Polymer class actually described
- Mannose- and glucose-dominated heteropolysaccharide
Reported molar ratio puts mannose at 5.02 and glucose at 4.48 but galactose at only 0.37 — fifth of seven sugars in a polymer named for galactose. Linkage analysis is likewise glucose- and mannose-led.
Zhao D. et al. 2020
[7]- Called it
- Water-soluble Aap
- Polymer class actually described
- Described as beta-1,3 linked
The beta-1,3 description is carried over from the group’s own earlier work rather than re-derived, and no repeating unit appears in the abstract.
Nilkhet et al. 2024
[4]- Called it
- Crude polysaccharide (APW-CP)
- Polymer class actually described
- Uncharacterised mixture
Potency tracked with total beta-glucan content across preparations. That is a correlation between extracts, not identification of the active molecule.
What this rules out: pooling these results into a single dose or a single mechanism. Until two groups characterise the same molecule and reproduce the same immune readout, “Auricularia polysaccharide” describes a category of extract, not a compound with a known active structure. A supplement label carrying that phrase is not telling you which of these four things, if any, is in the capsule.
Names, molar ratios and linkage analyses read from Perera 2018 [1], Perera 2020 [2], Bao 2020 [3], Nilkhet 2024 [4] and Zhao D. 2020 [7]
Restoring immune function in immunosuppressed animals
Cyclophosphamide model: cytokines and gut restoration
Kong et al. (2020) tested Auricularia polysaccharide fraction AAP1 in mice immunosuppressed by cyclophosphamide (CTX), a chemotherapy drug that depletes immune cells.[5]
AAP1 significantly enhanced immune organ indexes and stimulated serum levels of five cytokines: IFN-gamma, IL-2, IL-4, IL-10 and TNF-alpha. These span both Th1 (IFN-gamma, IL-2) and Th2 (IL-4, IL-10) arms of adaptive immunity, suggesting broad activity rather than selective polarization.[5]
Beyond cytokines, AAP1 upregulated mRNA expression of intestinal tight junction proteins (Claudin-1, Occludin, ZO-1), indicating gut barrier repair. It also restored gut microbiota composition toward that of the control group, decreasing the Firmicutes/Bacteroidetes ratio and increasing the relative abundance of short-chain fatty acid-producing bacteria.[5] The microbiota is the parameter the paper describes as restored toward control; the cytokines are reported as stimulated relative to the CTX group, which is a weaker claim than a return to normal.
A 2025 study repeated the CTX model with a stepwise enzymatic extraction that yielded both a peptide fraction (AAPP1) and a polysaccharide fraction (AAPS3).[6] Both significantly reversed CTX-induced decreases in thymus and spleen indices and reshaped the Bacteroidota/Firmicutes balance. The replication is useful — it is a second group reaching the same conclusion in the same model — but note that it also credits a peptide fraction with immunomodulatory activity, which further loosens the link between the observed effect and any specific polysaccharide.
The gut connection suggests a possible mechanism for oral polysaccharide immune effects: rather than being absorbed and acting systemically, the polysaccharides may reshape the gut microbial community, which in turn influences systemic immune function. For related research, see Auricularia and gut microbiome modulation.
Colitis prevention via microbiota modulation
Zhao D. et al. (2020) showed that oral pre-administration of a water-soluble Auricularia polysaccharide prevented DSS-induced colitis in mice, ameliorating weight loss, colon damage and mucosal inflammation, and protecting the intestinal barrier as measured by reduced plasma D-lactic acid and diamine oxidase.[7]
The most striking finding was that the protective effect was transferable. Horizontal feces transfer from polysaccharide-treated mice to untreated animals conferred the same colitis protection.[7]
Transmissibility is consistent with the reshaped microbiota carrying the benefit, and it is the strongest gut-mediation evidence in this literature. It is not proof. A horizontal feces transfer moves bacteria, but it also moves bacterial metabolites, host-derived factors and any residual polysaccharide, and this design does not isolate which of those did the work. Establishing that the microbiota is necessary would require something further — germ-free recipients, or selective depletion.
Enhancing vaccine responses — by injection, in chickens
Nguyen et al. (2012) took a different approach, testing whether sulfated derivatives of Auricularia auricula polysaccharides could serve as vaccine adjuvants.[8]
Chemical sulfation by the chlorosulfonic acid-pyridine method produced sAAPt, sAAP1 and sAAP2 from the parent fractions. In chicken peripheral lymphocytes, sAAPt and sAAP1 showed better proliferative effects than the unmodified parent compounds.[8]
The in vivo arm is where the details matter. Fourteen-day-old chickens were injected with the polysaccharides once daily for three days at the time of first Newcastle disease vaccination. Lymphocyte proliferation and antibody titer were then measured on days 7, 14, 21 and 28. sAAPt possessed the best efficacy, and the authors proposed it as a candidate immunopotentiator.[8]
Three things limit what this transfers to a human taking a capsule. The route was injection, not ingestion. The species was a bird. And the active agents were chemically sulfated derivatives, which are distinct molecules from the native polysaccharides in a mushroom. The result demonstrates that the immunostimulatory scaffold of Auricularia polysaccharides can be amplified by structural modification — a pharmaceutical-development observation, not a dietary one.
The adjuvant concept is worth separating from direct immunostimulation on its own terms. An adjuvant does not need to activate the immune system meaningfully by itself; it needs to increase the response to a co-administered antigen. The threshold for activity as an adjuvant may be lower than the threshold for standalone immune enhancement, so adjuvant efficacy does not predict supplement-level immune effects.
What Was Tested, and How It Got In
One of Eight Studies Used the Route You Would Use
Route of administration decides whether a finding says anything about eating wood ear mushroom. Four studies applied the polysaccharide straight onto cells. One injected it into chickens. Exactly one confirms oral dosing — and that study concluded the benefit travelled through the gut microbiota, not the polysaccharide itself.
| Study | Tier | Model | Route | What was measured |
|---|---|---|---|---|
| Perera 2018[1] | Cell | Macrophages in culture | Applied directly to cells | TLR4 binding; pro-inflammatory cytokine secretion |
| Perera 2020[2] | Cell | Macrophages in culture, resting and LPS-activated | Applied directly to cells | Phagocytosis and bactericidal activity up; NO, IL-6, TNF-alpha down in activated cells |
| Bao 2020[3] | Cell | RAW264.7 — mouse leukaemia-derived line | Applied directly to cells | Proliferation, nitric oxide, phagocytic ability |
| Nilkhet 2024[4] | Cell | THP-1 derived macrophages — human line | Applied directly to cells | M1 genes, CD86, IL-6, IL-1beta, TNF-alpha; anti-tumour effect on MCF-7 and MDA-MB-231 |
| Kong 2020[5] | Animal | Cyclophosphamide-immunosuppressed mice | Not stated in abstract | Immune organ indexes, five serum cytokines, tight junction mRNA, gut microbiota |
| Zhao M. 2025[6] | Animal | Cyclophosphamide-immunosuppressed mice | Not stated in abstract | Thymus and spleen indices reversed; gut microbiota rebalanced |
| Zhao D. 2020[7] | Animal | DSS colitis mice, plus feces transfer to untreated mice | Oral | Weight loss, colon damage, barrier markers, microbiota; effect transmissible by feces transfer |
| Nguyen 2012[8] | Animal | 14-day-old chickens, Newcastle disease vaccination | Injected, once daily for three days | Lymphocyte proliferation and antibody titre; sAAPt best efficacy |
| Any human study— | Missing | No human data at any dose | — | No trial has measured an immune outcome in people |
Reading the bottom row: the missing tier is not a technicality. Large polysaccharides are poorly absorbed intact, so a result obtained by dropping AAPS onto a macrophage or injecting it into a chicken carries no commitment about what a serving of wood ear does in a person. The one oral study that worked points away from direct immune-cell activation and towards the gut microbiome as the intermediary.
Models, routes and readouts read from references [1]–[8]; route recorded as stated by each source
Structure determines function: what the 2024 review establishes
Tang et al. (2024) reviewed the structural properties, bioactivities and structure-activity relationships of Auricularia auricula polysaccharides.[9]
The review's central observation is a caution rather than a conclusion: distinct structures have been reported for AAPs depending on the original source material and the extraction method used, and those structural differences lead to different bioactivities. The authors note explicitly that the structure-activity relationship of AAPs has scarcely been reviewed until now.[9] In other words, the field agrees that structure governs activity, and does not yet agree on which structure governs which activity.
That is consistent with what the primary studies show when read side by side. A glucuronoxylomannan with a mannan backbone (Perera) and a beta-glucan (implicated by Nilkhet's correlation) are different classes of molecule. No study in this literature has characterized the same polymer twice and reproduced the same immune readout.
This has practical implications for supplement quality. Extraction method, cultivation conditions and processing determine which polysaccharide fractions end up in a commercial product. A hot water extract and an alcohol precipitate from the same batch of wood ear may contain different polysaccharide profiles with different biological activities. Without standardization to a specified active fraction, a label reading "Auricularia polysaccharide" does not identify what is in the capsule.
- Cell & Lab Studiescompleted
TLR4 binding and structural requirements solved (Perera 2018); bidirectional macrophage response including endotoxin tolerance (Perera 2020); RAW264.7 activation (Bao 2020); M1 polarization in human THP-1 macrophages (Nilkhet 2024)
- Animal Studiescurrent
CTX-immunosuppressed mice with independent 2025 replication (Kong 2020; Zhao M. 2025); oral DSS colitis prevention with transmissible protection (Zhao D. 2020); injected vaccine adjuvant in chickens (Nguyen 2012)
- Case Reportsmissing
No published human case reports of immune effects from Auricularia polysaccharides
- Small Human Trialsmissing
No trial has measured any immune endpoint in humans at any dose or preparation
- Large Randomized Trial (200+)missing
None registered or published
- Meta-Analysismissing
No human trials exist to pool
The mechanistic work is unusually good for a food polysaccharide — a solved structure, a named receptor, and defined chemical requirements for binding. The translational work stops at rodents and one bird study. The ladder has no human rung at all, and the single oral animal study points to the gut microbiota rather than direct immune-cell activation as the route.
Assessment based on the nine primary sources cited in this article, 2012–2025
Who should be cautious
ModerateImmune modulation is not automatically desirable
Concern
A compound that changes macrophage signaling in either direction is not neutral for everyone. In autoimmune disease, added immune activation is the thing treatment is trying to avoid. In transplant recipients and others on deliberate immunosuppression, anything that modulates immune signaling could in principle interfere with the therapy that is keeping them well. The cyclophosphamide research is also frequently read as support for taking wood ear during chemotherapy — a setting where immune and drug interactions carry real consequences.
What the research says
No human data exists in any of these populations, which means the risk is uncharacterized rather than demonstrated to be low. The absence of reported harm in a literature containing zero human trials is not a safety finding. Wood ear eaten as a food has a long culinary history; concentrated polysaccharide extracts taken for an immune purpose are a different exposure.
Particularly relevant for: People with autoimmune conditions, transplant recipients, anyone on immunosuppressive therapy, and people undergoing chemotherapy
What to do
Treat concentrated Auricularia extracts as a medical decision to raise with your oncologist, rheumatologist or transplant team rather than a dietary one. This article is research summary, not medical advice.
Based on the absence of human safety or efficacy data across the nine sources reviewed
What remains unknown
The gap between these findings and clinical application is wide. Several specific issues limit translation:
No human immune data exists. Every study cited here used cell lines, mouse models, or chickens. Human immune responses to oral Auricularia polysaccharides have not been measured in any controlled trial. Immune cell activation in a culture dish does not predict measurable immune enhancement in a person eating wood ear mushroom.
Oral bioavailability is unclear. Large polysaccharide molecules are generally not absorbed intact through the gut wall. The feces transfer data from Zhao D. et al. (2020) is consistent with the immune effects being indirect, mediated through gut microbiota changes rather than direct polysaccharide-immune cell contact.[7] If that is the primary mechanism, then studies applying polysaccharides directly to macrophages may overstate their relevance to oral consumption.
The direction of effect is not fixed. The endotoxin-tolerance result means the same molecule can raise or lower inflammatory output depending on the state of the target cell.[2] Which direction dominates in a living human with an ordinary mix of resting and activated immune cells is unknown, and no study has attempted to find out.
Dose ranges are arbitrary. Cell culture studies use concentrations that do not correspond to achievable tissue levels after oral consumption. Animal doses have not been validated for human equivalence, and several of the papers reviewed here do not state the administration route in their abstracts at all.
Species differences matter and are unaddressed. The studies use A. auricula-judae (Perera, Zhao D.), A. auricula (Bao, Kong, Zhao M.) and A. polytricha (Nilkhet) as though results transfer between them. These are closely related but distinct species with potentially different polysaccharide profiles, and no study has compared them head to head on an immune endpoint.
Publication bias is present. The Auricularia immune literature is uniformly positive. Studies showing no macrophage activation or no immune restoration are far less likely to be published, creating a skewed evidence base. The real hit rate of Auricularia polysaccharide fractions for meaningful immune activation may be lower than the published record suggests.
Relevance to dietary consumption is unestablished. Most studies use isolated, purified fractions at defined concentrations. A serving of cooked wood ear contains an uncharacterized mixture of polysaccharides, proteins, melanin and dietary fiber. The immune effects of eating the whole mushroom cannot be inferred from studies of purified fractions, and the extraction and purification process itself may create or destroy bioactive structures. For how these immune mechanisms connect to gut-mediated pathways, see Wood Ear and gut-mediated immune enhancement. For the traditional use perspective alongside modern data, see Wood Ear for immune support: traditional and modern evidence.
The Bottom Line
Auricularia polysaccharides engage TLR4 on macrophages with defined structural requirements, and the mechanistic work behind that claim is unusually well done for a food polysaccharide. But the effect is bidirectional: the same molecule that activates resting macrophages suppresses already-activated ones, an endotoxin-tolerance-like response that makes "immune booster" the wrong description. The animal work is consistent — cytokine and gut-barrier restoration in cyclophosphamide-immunosuppressed mice, now replicated in 2025 — while the one oral study points to gut microbiota remodeling rather than direct immune-cell contact as the likely route. The four best-characterized preparations are structurally different molecules, so results cannot be pooled into a single mechanism or dose. No human trial has measured any immune outcome from Auricularia polysaccharides at any dose.
Frequently Asked Questions
Sources & References
- 1RTHM-00525·Perera, Namal et al. (2018). “Carboxylic and O-acetyl moieties are essential for the immunostimulatory activity of glucuronoxylomannan: a novel TLR4 specific immunostimulator from Auricularia auricula-judae..” Chemical communications (Cambridge.Study breakdown →PubMed →↩
- 2RTHM-00649·Perera, Namal et al. (2020). “Phagocytosis enhancement, endotoxin tolerance, and signal mechanisms of immunologically active glucuronoxylomannan from Auricularia auricula-judae..” International journal of biological macromolecules.Study breakdown →PubMed →↩
- 3RTHM-00607·Bao, Zhijie et al. (2020). “Isolation, purification, characterization, and immunomodulatory effects of polysaccharide from Auricularia auricula on RAW264.7 macrophages..” Journal of food biochemistry.Study breakdown →PubMed →↩
- 4RTHM-00897·Nilkhet, Sunita et al. (2024). “M1 macrophages polarized by crude polysaccharides isolated from Auricularia polytricha exhibit anti-tumor effect on human breast cancer cells..” Scientific reports.Study breakdown →PubMed →↩
- 5RTHM-00628·Kong, Xianghui et al. (2020). “Effects of Polysaccharides From Auricularia auricula on the Immuno-Stimulatory Activity and Gut Microbiota in Immunosuppressed Mice Induced by Cyclophosphamide..” Frontiers in immunology.Study breakdown →PubMed →↩
- 6RTHM-02219·Zhao, Ming et al. (2025). “Preparation of Auricularia auricula-Derived Immune Modulators and Alleviation of Cyclophosphamide-Induced Immune Suppression and Intestinal Microbiota Dysbiosis in Mice..” Life (Basel.Study breakdown →PubMed →↩
- 7RTHM-00667·Zhao, Di et al. (2020). “Polysaccharide isolated from Auricularia auricular-judae (Bull.) prevents dextran sulfate sodium-induced colitis in mice through modulating the composition of the gut microbiota..” Journal of food science.Study breakdown →PubMed →↩
- 8RTHM-00259·Nguyen, The Luong et al. (2012). “Immuno-enhancing activity of sulfated Auricularia auricula polysaccharides..” Carbohydrate polymers.Study breakdown →PubMed →↩
- 9RTHM-00913·Tang, Jun et al. (2024). “Structural properties, bioactivities, structure-activity relationships and bio-applications of polysaccharides from Auricularia auricula: A review..” International journal of biological macromolecules.Study breakdown →PubMed →↩