Summary

Here, we hypothesize that autologous adipose-derived regenerative cells (ADRCs) are a new option for patients living with retinitis pigmentosa. In contrast to a drug with a single mechanism of action, ADRCs regulate the multiple factors contributing to a patient’s loss of eyesight.

In 1857, Dr. Donders identified a group of incurable eye disorders he named retinitis pigmentosa (RP). But it was not as simple as that: Subsequently, researchers discovered over 100 genes that can contain mutations leading to retinitis pigmentosa. But genetic abnormalities do not clarify everything; half of RP cases lack family history and explanation.

Yet, despite the disease’s complexity, able investigators have mapped out RP’s degenerative process. Retinitis means inflammation of the retina. That inflammation leads to a spiral of degeneration of the retina and optic nerve.

In the presence of infection, injury, or disease, ADRCs home to sites of inflammation and initiate a repair process through multiple mechanisms of action.

Time For a New Option

Drug and gene therapy developers continue to pursue the failed “one molecule or gene for one disease model” for RP. This minimalist approach has not produced a drug or gene therapy that changes disease progression or improves patients’ best-corrected visual acuity (BCVA).

In the real world, the 100,000 people in the U.S. diagnosed with RP lack an option that slows, stabilizes, or reverses the disease’s progression. Instead, most are legally blind by age 40. Therefore, patients need a new standard of care regardless of the gene mutation or other underlying cause of RP.

Hypothesis

Here, we hypothesize that autologous Adipose-Derived Regenerative Cells (ADRCs) are a new option for patients living with retinitis pigmentosa. In contrast to a drug with a single mechanism of action, ADRCs regulate the multiple factors contributing to a patient’s loss of vision.

The cornerstone of our hypothesis is that all the body’s systems are interrelated and dependent. As such, multisystem dysfunction contributes to degenerative diseases, including RP ^{[1] [2] [3] [4] [5]}

Specifically, RP-related multisystem dysregulation results in:

1. Oxidative stress
2. Reduced nitric oxide levels
3. Elevated systemic inflammation
4. Abnormal immune response
5. Metabolic dysregulation
6. Endothelial dysfunction
7. Mitochondrial impairment
8. Autonomic dysfunction^{[6] [7] [8] [9]}

These abnormalities lead to apoptosis of the retinal photoreceptors and blindness. ^[10]

IV Protocol Rationale

We propose IV delivery of ADRCs based on:

1. A rat study mimicking human RP demonstrated that IV infusion is superior to subretinal delivery. “It would appear that stem cells exert their effect over the whole retina when administered systemically. In comparison, subretinal delivery of cells including bone marrow-derived cells usually results in rod and cone rescue” (S. Wang, 2010) ^[11]
2. A human study of umbilical cord MSCs (UCMSCs) confirmed the feasibility, safety, and potential benefits of systemically delivered stem cells. “Most patients improved their best-corrected visual acuity (BCVA) in the first three months. The proportions of patients with improved or maintained BCVA were 96.9%, 95.3%, 93.8%, 95.4%, 90.6%, and 90.6% at the 1st, 2nd, 3rd, 6th, 9th, and 12th-month follow-up, respectively. Most of the patients (81.3%) maintained or improved their visual acuities for 12 months.” (T. Zhao, 2020). The researchers also proposed that the breakdown of the blood-retinal barrier (BRB) in the progression of RP may allow infused cells to reach the impaired retinal tissue without requiring direct injection into the eye. ^{[12] [13] [14]}
3. A study of IV injection of UCMSCs vs. direct injection of a steroid showed: “UCMSC intravenous infusion shows slow but persistent action in alleviating ME [macular edema] and can improve the visual function for a longer time.”^[15]
4. A Japanese group compared the trophic factors secreted by fresh ADRCs vs. cultured ASCs (adipose-derived MSCs) from the same individual. The study indicates that ADRCs are more multifunctional and potent than cultured ASCs cells. ADRCs released a greater variety of cytokines or soluble proteins in significantly higher amounts than ASCs. ^[16]The favorable comparison noted above extends to MSCs derived from other sources, such as bone marrow, umbilical cord, and placenta.
5. Conversely, several direct-injection studies reported adverse events such as retinal tears and fibrosis.Therefore, IV infusion shows advantages in both safety and delivery.

AMBROSE Protocol for retinal diseases:

1. A board-certified plastic surgeon, using water-assisted liposuction (WAL), harvests 400 cc of lipoaspirate. WAL is causes minimal trauma to the patient and the harvested tissue, resulting in higher ADRC yields and greater viability.
2. The Celution® System liberates the ADRCs from the lipoaspirate.
3. A nurse inserts an IV catheter and delivers mannitol. Mannitol is a sugar alcohol that temporarily disrupts the BRB. It is a standard of care for delivering drugs into the back of the eye.
4. The ADRCs are delivered intravenously over a 20-minute infusion.

The outpatient procedure takes about five hours. Cell preparation takes approximately 2.5 of those hours, during which the patient rests comfortably.

 

 

ADRCs

The term adipose-derived regenerative cells (ADRCs) refers to a clinical-grade preparation of stromal vascular fraction (SVF). The inherent role of ADRCs is to maintain cellular, tissue, and systemic homeostasis.^{[17] [18] [19]}

ADRCs are a heterogeneous population of cells, including mesenchymal stem cells, other progenitor cells, fibroblasts, regulatory T cells, and macrophages. The mix includes a high percentage of endothelial cells, endothelial progenitor cells, macrophages, and leukocytes.

After homing to a site of inflammation, ADRCs release a secretome containing hundreds of cytokines and growth factors into the diseased microenvironment. The endogenous cells send signals back to the ADRCs.

This crosstalk instructs the individual cell types needed for repair to activate – and those that are not needed (or harmful) to stand down. Put differently, the plethora of biological agents in the secretome restores cellular stability and homeostasis.

 

ADRCs – Miracle-Gro for nerve repair

Miracle-Gro feeds the plants in your garden with the nutrients they need to grow healthy roots, stems, petals, and leaves. Just as there are situations in which we fertilize a plant lacking vital nutrients, ADRCs secrete growth factors essential to the health of our aging brains, hearts, muscles, nerves, and so on. ^[20]

One such group consists of neurotrophic factors (NTFs). Neuro refers to nerves, while trophic comes from Ancient Greek trophikós, meaning “of food or nourishment.” In other words, NTFs feed our neurons and nerves with nutrients.

Notably, brain-derived neurotrophic factor (BDNF) stimulates new neurons, nerve cell connections, and nerves. It also repairs the myelin sheath surrounding the nerves. Further, this remarkable molecule is anti-inflammatory and anti-apoptotic. Diminished BDNF levels correlate with the progression of RP. ^{[21] [22] [23] [24] [25]}

A recent discovery of neuroimmune cells in ADRCs is notable. Neuroimmune cells innervate tissues and release BDNF.^[26] Additionally, other cells in adipose tissue secrete an abundance of neurogenerative factors.

Human studies show ADRCs release factors that:

• Downregulate inflammatory-autoimmune markers, including but not limited to TNF-α and TH17.
• Reduce the production of Endothelin-1, a known constrictor of blood vessels and a culprit in subsets of RP patients.
• Include placental growth factor (PGF), stromal cell-derived factor-1 (SDF-1), and vascular endothelial growth factor (VEGF), all of which assist in the growth and stabilization of new blood vessels. These growth factors are also anti-inflammatory and anti-apoptotic.
• Promote the switch from inflammatory M1 macrophages to anti-inflammatory M2 macrophages through prostaglandin E2 (PGE2).

 

Permeating the blood-retinal barrier

A critical concern of physicians and patients regarding ocular diseases is whether adult stem cells can be delivered non-invasively and can safely permeate the blood-retinal barrier (BRB), an extension of the blood-brain barrier. The BRB protects our brains, eyes, and the spinal canal from microbial invaders. It is our central nervous system’s version of Fort Knox. Still, instead of a granite-lined concrete structure, epithelial and endothelial cells line the outer and inner blood-retinal barrier, respectively. ^[27]

Three mechanisms allow the migration of MSCs and the ADRC secretome into the back of the eye.

1. Mannitol, a safe sugar alcohol, temporarily opens the BBB.
2. ADRCs release cytokines that permeate the BBB.
3. MSCs possess the ability to cross the BBB. ^{[28] [29]}

As the lymphatic vessels parallel the vascular system, they may provide a route through which stem cells migrate from the spleen, thereby bypassing the blood-brain barrier. ^[30]

The Celution System is a closed, sterile lab-in-a-box. Celution liberates autologous clinical-grade ADRCs from lipoaspirate at the point of care.

Celution has been approved for clinical use in more than 40 countries,including the United Kingdom, Japan, South Korea, New Zealand, and countries within the European Union. Additionally, the FDA has approved Celution for nine clinical trials.

Since Celution was approved in Europe and Japan in 2007, no cell-related adverse events have been reported in trials, studies, or clinical use.^[32]

 

 

[1] Dantzer R. Neuroimmune Interactions: from the brain to the immune system and vice versa. Physiol Rev. 2018;98(1):477-504.

[2] Tracey KJ. The inflammatory reflex. Nature. 2002;420(6917):853–859.

[3] Blaszkiewicz M et al. The involvement of neuroimmune cells in adipose innervation. Mol Med. 2020;26:126.

[4] Zmora N et al. The role of the immune system in metabolic health and disease. Cell Metabolism. 2017;25(3):506–521.

[5] Amiya E et al. The relationship between vascular function and the autonomic nervous system. Ann Vasc Dis. 2014;7(2):109–119.

[6] Okita A, Murakami Y, Shimokawa S, et al. Changes of serum inflammatory molecules and their relationships with visual function in retinitis pigmentosa. Invest Ophthalmol Vis Sci. 2020;61(11):30.

[7] Vinik AI. The conductor of the autonomic orchestra. Front Endocrinol (Lausanne). 2012;3:71.

[8] Limoli PG et al. Antioxidant and biological properties of mesenchymal cells used for therapy in retinitis pigmentosa. Antioxidants. 2020;9(10):983.

[9] Sorrentino FS, Bonifazzi C, Perri P. The role of the endothelin system in the vascular dysregulation involved in retinitis pigmentosa. J Ophthalmol 2015;2015:405234.

[10] Murakami Y et al.  C-reactive protein and progression of vision loss in retinitis pigmentosa. Acta Ophthalmol. 2018;96(2):e174–e179.

[11] Wang S, Lu B, Girman S, Duan J, McFarland T, et al. Non-invasive stem cell therapy in a rat model for retinal Degeneration and vascular pathology. PLoS One. 2010;5(2):e9200.

[12] Zhao T et al. Intravenous infusion of umbilical cord mesenchymal stem cells maintains and partially improves visual function in patients with advanced retinitis pigmentosa. Stem Cells Dev. 2020;29(16):1029–1037.

[13] Grant ZL et al. Blocking endothelial apoptosis revascularizes the retina in a model of ischemic retinopathy. J Clin Invest. 2020;130(8):4235-4251.

[14] Lang M et al. Vascular dysfunction in retinitis pigmentosa. Acta Ophthalmol. 2019;97(7):660–664.

[15] Zhao T, Lie H, Wang F, Liu Y, Meng X, Yin Z, Li S. Comparative study of a modified sub-Tenon’s capsule injection of triamcinolone acetonide and the intravenous infusion of umbilical cord mesenchymal stem cells in retinitis pigmentosa combined with macular edema. Front Pharmacol. 2021;12:694225.

[16] Hirose Y et al. Comparison of trophic factors secreted from human adipose-derived stromal vascular fraction with those from adipose-derived stromal/stem cells in the same individuals. Cytotherapy. 2018;20(4):589–591.

[17] Kesten S, Fraser JK. Autologous adipose derived regenerative cells: a platform for therapeutic applications. Surg Technol Int. 2016;29:38–44.

[18] Vizoso FJ et al. Mesenchymal stem cells in homeostasis and systemic diseases: hypothesis, evidences, and therapeutic opportunities. Int J Mol Sci. 2019;20(15):3738.

[19] Caplan AI. Mesenchymal stem cells: time to change the name! Stem Cells Transl Med. 017;6(6):1445–1451.

[20] A Caplan Al. MSCs: The sentinel and safe-guards of injury. J Cell Physiol. 2016;231(7):1413–1416.

[21] Razavi S et al. Neurotrophic factors and their effects in the treatment of multiple sclerosis. Adv Biomed Res. 2015;4:53.

[22] Huang JK et al. Myelin regeneration in multiple sclerosis: targeting endogenous stem cells. Neurotherapeutics. 2011;8(4):650–658.

[23] Lopatina T et al. Adipose-derived stem cells stimulate regeneration of peripheral nerves: BDNF secreted by these cells promotes nerve healing and axon growth de novo. PLoS One. 2011;6(3):e17899.

[24] Suganuma S et al. Uncultured adipose-derived regenerative cells promote peripheral nerve regeneration. J Orthop Sci. 2013;18(1):145–151.

[25] Xu D et al. Brain-derived neurotrophic factor reduces inflammation and hippocampal apoptosis in experimental Streptococcus pneumoniae meningitis. J Neuroinflammation. 2017;14(1):156.

[26] Blaszkiewicz M et al. The involvement of neuroimmune cells in adipose innervation. Mol Med. 2020;26:126.

[27] Campbell M, Humphries P. The blood-retina barrier: tight junctions and barrier modulation. Adv Exp Med Biol. 2012;763:70–84.

[28] Liu L et al. From blood to the brain: can systemically transplanted mesenchymal stem cells cross the blood-brain barrier? Stem Cells Int. 2013;2013:435093.

[29] Laroni A et al. Mesenchymal stem cells for the treatment of neurological diseases: Immunoregulation beyond neuroprotection. Immunol Lett. 2015;168(2):183–190.

[30] Absinta M et al. Human and nonhuman primate meninges harbor lymphatic vessels that can be visualized non-invasively by MRI. eLife. 2017;6:e29738.

[31] Perin EC, Willerson JT. Buying New Soul. J Am Coll Cardiol. 2012;60(21):2250–2251.