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TB-500 Benefits: What this healing peptide does - SeekPeptides

Firstly, TB-500 is a synthetic version of Thymosin Beta-4, a protein your body naturally produces. It's a 43-amino acid peptide that signals your body to repair damaged tissue and build new blood vessels. Your thymus gland produces Thymosin Beta-4 naturally. T

Firstly, TB-500 is a synthetic version of Thymosin Beta-4, a protein your body naturally produces.

It's a 43-amino acid peptide that signals your body to repair damaged tissue and build new blood vessels.

Your thymus gland produces Thymosin Beta-4 naturally.

TB-500 is the synthetic, injectable version. Same structure, same effects.

The name TB-500 refers specifically to a synthetic fragment that contains the active healing region.

It's more stable and easier to manufacture than full Thymosin Beta-4.

The legal status is familiar if you know peptides. Not FDA-approved for human use. Sold as a research chemical. Legal to buy in most countries. Widely used despite research-only labeling.

For complete TB-500 information, read our comprehensive TB-500 guide.

Benefit #1: Accelerated tissue healing

This is TB-500's primary benefit. It speeds up the repair of damaged tissue throughout your body.

TB-500 promotes cell migration to injury sites.

Your body's repair cells - fibroblasts, keratinocytes, endothelial cells - move faster to damaged areas. More repair cells at the injury means faster healing.

The mechanism is elegantly simple.

Animal studies demonstrate TB-500 accelerates healing across multiple tissue types.

Muscle tears heal faster. Tendon injuries improve.

Ligament damage repairs more effectively.

Even skin wounds close quicker.

Some cardiac injury models show heart tissue damage improving with TB-500 administration.

The real-world timeline requires patience.

Week one and two show minimal visible change.

You're loading the peptide into your system.

Week three and four bring noticeable pain reduction and improved mobility.

Week five through eight deliver clear healing progress.

By week nine through twelve, chronic injuries show significant improvement.

TB-500 is slower than BPC-157 initially, but it produces better long-term tissue quality.

The trade-off is worth it for stubborn injuries.

For injury-specific protocols, see best peptides for injury recovery.

Benefit #2: New blood vessel formation

TB-500 is one of the most potent angiogenic peptides available.

Angiogenesis means your body grows new capillaries - tiny blood vessels that deliver oxygen and nutrients to tissue.

This matters enormously for healing. Injured tissue needs more blood flow, not less. New blood vessels create permanent improved circulation to damaged areas.

The effect isn't temporary vasodilation like you'd get from a hot shower, but it's actual new vessel growth.

Tendons heal faster because they have poor natural blood supply. Muscle recovers quicker post-workout because blood flow improves.

Chronic injuries finally get adequate circulation. Scar tissue receives blood flow for remodeling.

Studies in animals show TB-500 significantly increases blood vessel density in damaged tissue.

The new vessels persist long after you stop the peptide.

Benefit #3: Reduced inflammation

TB-500 doesn't suppress inflammation like NSAIDs. It resolves it more efficiently. There's a critical difference.

TB-500 modulates cytokines - the inflammatory signaling molecules your body uses to coordinate immune response. It reduces excessive inflammation while preserving your immune response. You're not shutting down your body's healing signals.

You're optimizing them.

This feels like less joint pain and swelling.

Reduced morning stiffness, improved range of motion, better overall mobility, the inflammation resolves faster, so you spend less time hurting and more time healing.

Compared to NSAIDs, the difference is stark.

NSAIDs block inflammation, slow healing, and damage your gut.

TB-500 resolves inflammation, accelerates healing, and causes no gut issues. It's safer for long-term use because it works with your body's healing process instead of fighting against it.

Benefit #4: Reduced scar tissue formation

Scar tissue is your body's quick fix for damage.

It patches the hole fast. But it's inferior to original tissue in every way.

Less flexible, weaker, more prone to re-injury.

TB-500 promotes proper tissue remodeling instead of scar tissue formation.

Your body rebuilds actual functional tissue rather than just patching the damage with collagen.

The result is better long-term tissue quality, reduced risk of re-injury, improved flexibility, better strength in repaired tissue.

For existing scar tissue, TB-500 can help remodel old damage over time, not overnight, but gradual improvement over eight to twelve weeks is common.

This is particularly valuable for chronic injuries that healed poorly years ago.

That ankle sprain from high school that never quite felt right?

TB-500 might finally fix it properly.

Benefit #5: Improved flexibility and mobility

This benefit surprises most users. TB-500 improves tissue flexibility even in areas you're not directly targeting. It's not just your injured shoulder getting better.

Your hips feel looser.

Your lower back moves easier.

Everything improves.

TB-500's systemic effects reduce tissue stiffness and adhesions throughout your body.

It's not just healing injuries. It's improving overall tissue quality.

Users report better range of motion in joints, reduced muscle tightness, improved athletic performance, less morning stiffness, and easier stretching.

Flexibility improvements usually show up weeks four through six of consistent use. It's subtle at first.

Then one day you notice you can touch your toes again without warming up, or your shoulder reaches further overhead. Small improvements that compound into significant mobility gains.

Benefit #6: Faster muscle recovery

Athletes use TB-500 not just for injuries but for enhanced recovery between training sessions.

TB-500 accelerates muscle fiber repair post-workout. Your muscles rebuild faster, letting you train more frequently or with higher volume.

This means you can train five to six days per week sustainably.

Higher training volume becomes tolerated. Less delayed onset muscle soreness after brutal workouts. Better progression in strength and hypertrophy. For bodybuilders and athletes, TB-500 combined with growth hormone peptides creates an optimal recovery environment.

For muscle-building protocols, read best peptides for muscle growth.

Who benefits most from TB-500

Not everyone needs TB-500. But certain people benefit dramatically.

People with chronic injuries see the best results.

Those nagging issues that won't heal.

Multiple injury sites. Years-old injuries that never quite recovered. Injuries from overuse that just keep recurring.

TB-500's systemic effects are ideal when you have multiple problem areas.

Athletes training at high volume need TB-500's recovery enhancement. Five to six days per week training. Multiple training sessions daily.

The need for faster recovery between sessions.

Preventing overuse injuries before they happen.

Post-surgical recovery accelerates with TB-500. After ACL repair, rotator cuff surgery, meniscus surgery, any orthopedic procedure.

TB-500 speeds surgical site healing and reduces scar tissue formation.

Your physical therapist will notice you're ahead of schedule.

People with poor natural healing capacity respond exceptionally well.

Over forty years old. History of slow recovery.

Multiple failed treatments for chronic issues. Chronic inflammation that won't resolve. Age-related decline in healing capacity responds particularly well to TB-500.

How to use TB-500

TB-500 requires a loading phase followed by maintenance.

The standard protocol starts with loading for weeks one through four. Inject 2.5 to 5mg per injection, twice weekly, usually Monday and Thursday.

Total weekly dose is 5 to 10mg.

The purpose is building up tissue concentrations.

Maintenance phase runs weeks five through twelve. Inject 2 to 3mg per injection, once weekly.

Total weekly dose is 2 to 3mg.

The purpose is maintaining therapeutic levels while you heal.

Some people dose by body weight at 30 to 60 mcg per kilogram for loading.

An 80kg person would inject 2,400 to 4,800mcg - that's 2.4 to 4.8mg - per injection during loading phase.

TB-500 works systemically.

You can inject anywhere subcutaneous. Abdomen, thigh, or arm all work equally. It circulates through your bloodstream and finds damaged tissue throughout your body. Unlike BPC-157, location doesn't matter.

Use our TB-500 dosage calculator for complete loading and maintenance protocols.

TB-500 vs BPC-157 benefits

The two most popular healing peptides. The benefits differ meaningfully.

TB-500 works systemically throughout your body. It's better for multiple injuries. Superior for chronic issues. Builds new blood vessels. Improves overall tissue quality.

Slower initial results but worth the wait.

BPC-157 works locally at the injection site. It's better for single acute injuries. Faster pain relief. Protects gut lining. More immediate results. Inject near the injury for best effect.

For acute injuries, start with BPC-157. For chronic injuries, start with TB-500. For severe injuries, stack both peptides together.

For complete comparison, read BPC-157 vs TB-500.

Expected timeline for TB-500 benefits

Be patient. TB-500 takes time to build up in your system.

Week one and two show minimal noticeable changes.

Subtle reduction in inflammation maybe. You're building tissue concentrations. Trust the process even though you feel nothing yet.

Week three and four bring the first real improvements.

Reduced pain and swelling. Better mobility. Improved sleep because you're hurting less at night. This is when you know it's working.

Week five through eight show clear healing progress.

Return to activity becomes possible. Flexibility keeps improving. Training capacity increases. You're genuinely better, not just less hurt.

Week nine through twelve deliver major improvements. Chronic injuries respond. Tissue quality optimizes. Re-injury risk reduces. You're approaching full function again.

Beyond week twelve, continue maintenance dosing if needed. Sustain improvements. Maintain long-term tissue health. Enjoy prevention benefits.

TB-500 is a marathon, not a sprint. The benefits accumulate over weeks.

Stacking TB-500 with other peptides

TB-500 works well in combination with other peptides.

The TB-500 plus BPC-157 stack is the gold standard for serious injuries. Use TB-500 at 5mg twice weekly during loading.

Use BPC-157 at 250 to 500mcg twice daily near the injury. Run the stack for eight to twelve weeks. Result is fast pain relief from BPC-157 combined with long-term healing from TB-500.

For athletes wanting maximum recovery and performance, stack TB-500 with growth hormone peptides. TB-500 at 2.5mg twice weekly.

Ipamorelin at 200mcg three times daily. CJC-1295 at 200mcg twice weekly. Run this stack for twelve to sixteen weeks.

Use our peptide stack calculator to plan combinations safely.

Side effects and safety

TB-500 is generally very well-tolerated.

Common side effects are rare but include temporary tiredness after injection.

Mild lethargy for twenty-four hours.

Slight injection site irritation.

Head rush or warmth sensation occasionally.

Vivid dreams rarely.

Serious side effects are very rare. Allergic reaction to the peptide. Excessive angiogenesis theoretically. Injection site infection from poor technique.

Don't use TB-500 if you have active cancer diagnosis, are pregnant or breastfeeding, recently had eye surgery, or have known peptide allergies. The angiogenesis effect could promote cancer growth or blood vessel formation in the eye.

TB-500 doesn't interact with most medications. Monitor closely if taking blood thinners due to angiogenesis effects potentially affecting clotting.

Dosing mistakes that reduce benefits

Get the protocol right to see maximum benefits.

Skipping the loading phase by going straight to maintenance dosing means you never build adequate tissue concentrations. Complete the four to six week loading phase at higher doses. Don't try to save money here.

I

nconsistent dosing by injecting randomly rather than scheduled twice weekly reduces effectiveness. Set a consistent schedule like Monday and Thursday.

Don't skip doses because you feel fine that week.

Stopping too early when you feel better at week four wastes the protocol. Benefits haven't fully materialized yet. Complete the full twelve-week protocol for chronic injuries. The last month is when tissue quality really improves.

Underdosing by using 1mg twice weekly thinking it saves money puts you below therapeutic threshold. Use proper loading doses of 2.5 to 5mg. Saving peptide here just means not getting results.

Wrong expectations about immediate results like BPC-157 delivers leads to quitting early. Understand TB-500 is slower but produces better long-term results. Week three is when you'll notice changes, not day three.

For complete dosing calculations, read how to calculate peptide dosages.

Reconstitution and preparation

TB-500 ships as powder. You mix it before use. You need TB-500 vials in 5mg or 10mg size, bacteriostatic water, insulin syringes, and alcohol prep pads.

For a 5mg vial, add 2ml bacteriostatic water.

This creates 2,500mcg per ml concentration.

A 2.5mg dose equals 1ml or 100 units.

A 5mg dose equals 2ml which requires two separate 1ml syringes.

For 10mg vials, add 2ml water to create 5,000mcg per ml concentration. A 2.5mg dose equals 0.5ml or 50 units. A 5mg dose equals 1ml or 100 units. The higher concentration makes larger doses easier to inject.

For complete step-by-step instructions, read how to reconstitute peptides.

Use our peptide reconstitution calculator for exact mixing ratios.

Cost of TB-500 protocols

TB-500 is more expensive than BPC-157 due to higher doses required. Typical pricing for 5mg vials runs $40 to $55 per vial. A three-pack costs $110 to $150. A five-pack costs $180 to $250.

A complete twelve-week protocol costs significant money.

Loading phase for four weeks needs 40mg total, which is eight vials costing $320 to $440.

Maintenance phase for eight weeks needs 20mg total, which is four vials costing $160 to $220. T

otal is sixty milligrams requiring twelve vials at $480 to $660.

A budget option using lower doses runs cheaper. Loading at 2.5mg twice weekly needs 20mg total or four vials. Maintenance at 2mg weekly needs 16mg total or four vials. Total is eight vials costing $320 to $440.

Use our peptide cost calculator to budget accurately.

TB-500 for specific injuries

Different injury types benefit from TB-500 in specific ways.

Tendon injuries like Achilles or rotator cuff benefit from new blood vessels growing into the tendon. Timeline is six to eight weeks for improvement.

Stack with BPC-157 for faster results.

Muscle tears benefit from faster repair and less scar tissue formation.

Timeline is four to six weeks for recovery. Best for chronic or recurring tears that keep coming back.

Ligament damage benefits from improved healing and better tissue quality. Timeline is eight to twelve weeks for significant improvement. Stack with BPC-157 for acute injuries.

Post-surgical use brings accelerated wound healing and reduced scarring. S

tart one to two weeks post-surgery once incision is closed. Run for eight to twelve weeks.

Chronic overuse injuries benefit from systemic recovery with multiple sites healing simultaneously. Timeline is eight to sixteen weeks for full benefits. Consider continuing low-dose maintenance for prevention.

Real user results

Real people report meaningful improvements with TB-500.

One user with chronic shoulder impingement couldn't lift his arm above shoulder level for six months. Physical therapy wasn't working. Week four of TB-500 brought less pain. Week eight brought return to overhead pressing. Not one hundred percent but eighty percent improvement was life-changing.

A hamstring tear case involved a grade two tear with doctors saying twelve weeks minimum. Using TB-500 with BPC-157, the athlete returned to light training at week five. Full training at week seven. Saved the entire season.

A runner with multiple overuse injuries in knee, hip, and ankle tried everything. All chronic issues. TB-500 helped all three simultaneously. Wasn't fast but by week ten she was running pain-free for the first time in years.

Post-ACL surgery, one user started TB-500 at week two post-op. Physical therapist said recovery was ahead of schedule. Less swelling, better range of motion, back to sport two months ahead of typical timeline.

Comparing TB-500 to alternatives

TB-500 stacks up favorably against other treatment options.

Physical therapy is essential and TB-500 enhances it.

Use together for optimal results.

TB-500 enables more aggressive PT by reducing pain and accelerating tissue repair.

Platelet-rich plasma offers one-time injection costing $500 to $1,500.

TB-500 is an ongoing protocol that's more affordable overall.

TB-500 works systemically throughout your body, not just at the injection site.

Stem cell therapy is very expensive at $3,000 to $10,000 per treatment.

TB-500 costs a fraction of that.

Similar angiogenesis and healing benefits for dramatically less money.

For recovery comparison with other options, read peptides vs SARMs.

Long-term use and maintenance

Short-term protocols of eight to twelve weeks work perfectly.

Most people use TB-500 to heal specific injuries then stop. This is the standard approach.

Long-term maintenance at low doses appeals to some athletes.

Staying on 2mg weekly indefinitely provides injury prevention, enhanced recovery capacity, and tissue quality maintenance.

It's not necessary but some high-level athletes choose this approach.

A cycling approach alternates twelve weeks on, eight to twelve weeks off, then repeat as needed.

This gives receptors time to reset while maintaining most benefits during off periods.

No human studies on long-term TB-500 use exist.

Theoretical concerns about prolonged angiogenesis make most people cycle rather than use continuously. The conservative approach is probably smart until we have more data.

Where to buy TB-500

Quality varies significantly between vendors, source carefully.

Verify third-party testing that's batch-specific, and heck for recent test dates within three months.

Confirm purity above ninety-eight percent. Inspect proper packaging and clear labeling.

Red flags include no certificates of analysis available, suspiciously cheap prices compared to market rate, poor reviews or no reviews at all, and unprofessional websites that look thrown together.

For complete vendor evaluation, read best peptide vendors.

The bottom line on TB-500 benefits

TB-500 delivers real, measurable benefits for tissue healing and recovery. Not overnight. Not miraculously. But consistently over weeks of proper use.

The primary benefits are accelerating healing by thirty to fifty percent faster, building new blood vessels that persist long-term, reducing inflammation without suppressing immune function, improving tissue quality over time, decreasing scar tissue formation, and enhancing flexibility throughout your body.

It's best for chronic injuries, multiple injury sites, post-surgical recovery, and athletes needing enhanced recovery capacity.

The standard protocol runs twelve weeks total.

Loading at 2.5 to 5mg twice weekly for four weeks. Maintenance at 2 to 3mg weekly for eight weeks. Simple. Effective. Proven.

Calculate your protocol with our free tools. TB-500 dosage calculator for complete protocols. Peptide reconstitution calculator for mixing guide. Peptide cost calculator for budget planning.

TB-500 works. Give it the full twelve-week protocol. Your injuries will heal better than they would naturally.

CONNECTED / MODULES

Post-session references

Selected from shared article topics. Source links are retained where available.

01

Handling & safety lane

Source-derived education, not individual medical guidance or an instruction to dose.

DOSAGE SOURCE

TB-500 Dosage Calculator

TB-500 is usually shipped in the form of freeze dried (lyophilized) powder that should be reconstituted with a solution like bacteriostatic water. As most published TB-500 research to date has involved rodents, there is limited data from which to calculate TB-500 dosage in an experimental setting. Researchers may refer to the following TB-500 dosing protocol in injury recovery contexts: Daily Dosage: 2mg TB-500, administered daily via subcutaneous injection Study Duration: 15 days. Notes: This protocol requires three TB-500 10mg vials per test subject per course. Depending on the subject’s recovery, researchers may continue to administer a lowered maintenance dosage of 1mg daily until full or near-full recovery.
STORAGE

Storage, Reconstitution, and Potency Retention

TB-500 is supplied as a lyophilized powder and must be stored at −20°C before reconstitution. Once mixed with bacteriostatic water (0.9% benzyl alcohol), the peptide remains stable at 2–8°C for up to 28 days. Temperature excursions above 8°C cause irreversible denaturation—the amino acid sequence folds incorrectly, rendering the peptide biologically inactive. Our experience with research-grade peptides shows that the most common failure point isn't storage—it's reconstitution technique. Injecting bacteriostatic water directly onto the lyophilized pellet creates shear forces that break disulfide bonds. The correct method: inject the water slowly down the side of the vial, allowing it to dissolve the powder through passive diffusion rather than direct impact. Vigorous shaking also denatures peptides—gentle swirling is sufficient. Another overlooked factor: vial pressure equilibration. Each time a needle pierces the stopper, air enters the vial, creating positive pressure that forces solution back through the needle during withdrawal. This introduces particulate contamination and oxidative exposure. Drawing TB-500 from a vial more than 10 times significantly reduces potency due to cumulative oxidative degradation. For researchers using Real Peptides' small-batch synthesis protocols, single-use vials eliminate this contamination risk entirely.
02

Question drills

Open a question for its connected answer.

01What If You Need to Measure TB-500 Gene Expression Directly in Your Study?+

Isolate RNA at 12–24 hours post-treatment for peak transcriptional signal. Use RT-qPCR with primers for VEGF-A, ANGPT2, MMP2, and MMP9. These are the most reliable tb-500 gene expression markers. Normalize to housekeeping genes (GAPDH, beta-actin, HPRT1). If you're working with tissue samples rather than cell culture, expect higher variability due to mixed cell populations. Endothelial and fibroblast markers may need to be analyzed separately via immunohistochemistry to confirm which cell types are responding.

SOURCE / realpeptides.co ↗
02What If I Start TB-500 Immediately After an Acute Injury?+

Initiate with a 2.5–5.0mg loading dose within 24 hours, then continue 2.0mg twice weekly for at least 4 weeks. TB-500's MMP-9 suppression effect is most pronounced when the peptide is present during the acute inflammatory phase (0–72 hours post-injury), and front-loading the dose compensates for the fact that inflammatory cascades are already active. Research models show that administration within 24 hours captures approximately 70% of the benefit seen with pre-cycle protocols, dropping to 50–60% if delayed to 48–72 hours.

SOURCE / realpeptides.co ↗
03What If I Start TB-500 During a Peak Training Block?+

Don't. TB-500 promotes tissue repair through fibroblast migration and collagen synthesis, but these processes require reduced mechanical load to operate effectively. Injecting TB-500 while squatting and deadlifting at 85%+ of your 1RM four times per week creates a cycle of continuous microtrauma that interrupts collagen remodeling before it can strengthen tissue. The peptide can't outpace the damage rate during high-volume training. Schedule TB-500 loading phases during deload weeks or off-season blocks when training volume drops by 40–50% and intensity stays moderate.

SOURCE / realpeptides.co ↗
04What If I Experience No Improvement After Four Weeks on TB-500?+

Reassess your loading protocol first. TB-500 studied achilles tendonitis outcomes depend on pairing peptide therapy with progressive mechanical stimulus. If you've been resting entirely, the peptide may improve vascularization without triggering collagen alignment because there's no tensile load directing fiber orientation. Secondly, verify peptide purity and storage. Degraded TB-500 (exposed to heat or improper reconstitution) loses bioactivity. If both factors are controlled and symptoms persist, consider alternative diagnoses: insertional Achilles tendonitis responds differently than mid-portion tendonitis, and partial tears may require imaging-guided intervention beyond peptide therapy. Consult a sports medicine physician for ultrasound evaluation before extending peptide use beyond eight weeks.

SOURCE / realpeptides.co ↗
05What If the Certificate of Analysis Shows 95% Purity Instead of 98%?+

Do not use the peptide for any controlled research. HPLC purity below 98% means the remaining 2–5% is unidentified compounds. Potentially synthesis byproducts, degradation fragments, or inactive analogs. These impurities introduce uncontrolled variables that make data interpretation impossible. Contact the supplier for a replacement batch or refund. A reputable supplier will issue credit immediately without requiring you to ship the flawed batch back. Suppliers who resist this are signaling they don't stand behind their manufacturing process.

SOURCE / realpeptides.co ↗
03

Evidence cooldown

Research context and source excerpts for a slower second read.

RESEARCH

The Future of TB-500 Research in 2026 and Beyond

Looking ahead, the trajectory for TB-500 research in 2026 is incredibly promising. We anticipate continued exploration into its role in chronic disease management, particularly in areas like fibrosis, autoimmune conditions, and age-related tissue degeneration. The anti-inflammatory and regenerative TB-500 benefits make it a formidable candidate for addressing complex physiological challenges. Our commitment at Real Peptides is to support this ongoing discovery by maintaining the highest standards of peptide synthesis. We believe that by providing researchers with impeccably pure compounds, we're directly contributing to breakthroughs that could redefine health and recovery paradigms. Honestly, though, the pace of discovery is relentless, and we’re here to ensure your research stays ahead of the curve. Discover Premium Peptides for Research that meet your exact specifications. We're deeply invested in the scientific community, and our mission is to facilitate your groundbreaking work. We encourage you to explore our full range of high-purity research peptides and consult our resources on www.realpeptides.co to further your understanding of compounds like TB-500 (thymosin Beta-4) and their profound potential. The journey of scientific discovery is a shared one, and we're proud to be your trusted partner every step of the way. We aim to be your first and last stop when you need to Find the Right Peptide Tools for Your Lab.

RESEARCH

Key Insights from Our Research Team at Real Peptides

Our collective expertise at Real Peptides tells us that the future of regenerative medicine, particularly for challenging areas like ocular tissue, rests heavily on understanding and harnessing the body's intrinsic healing capabilities. TB-500 corneal repair isn't just about applying a substance; it's about providing the molecular cues that guide natural repair processes more efficiently and effectively. We've observed that researchers who prioritize high-purity peptides consistently achieve more reliable and interpretable results, accelerating their understanding of these complex biological interactions. It's a foundational principle for us. We also believe that continued collaboration across disciplines will be vital. Ophthalmologists, biologists, pharmacologists—all have crucial roles to play in advancing the science of TB-500 (thymosin Beta-4) and its application. The insights gained from diverse perspectives are what truly propel innovation. We're always eager to engage with researchers who are pushing these boundaries, providing them with the highest quality research materials and support to facilitate their groundbreaking work. Our full range of All Peptides is available to support a vast array of research endeavors.

05

Product & matchup locker

Linked catalog and comparison files.

Comparison

TB-500 vs Thymosin Beta-4 vs BPC-157: Comparisons

Three comparisons matter most for anyone trying to make sense of TB-500: how the fragment relates to its parent protein, how it relates to recombinant clinical-grade thymosin beta…