RENAL STEM CELLS IN DISEASE AND TREATMENT

1. RENAL STEM CELL AND IT’S
ROLE IN KIDNEY DISEASES AND
TREATMENT
DR ANIRUDDHA RUDRA
PDT
NEPHROLOGY
NRSMCH

2. STEM CELLStem cell possesses two properties:
1. Self-renewal:
- The ability to go through numerous cycles of cell division while maintaining the undifferentiated state.
- Asymmetric cell division: a stem cell divides into one mother cell that is identical to the original stem cell
and another daughter cell that is differentiated
2. Potency: the capacity to differentiate into specialized cell types.

3. STEM CELL POTENCY

4. TELOMERASE
• Telomerase is a ribonucleoprotein that adds a species-dependent telomere
repeat sequence to the 3' end of telomeres.
• Telomere : a region of repetitive sequences at each end of eukaryotic
chromosomes
• Location:
- stem cells
- male sperm cells
- epidermal cells
- activated T and B lymphocytes
Somatic cells do not express telomerase.

5. TELOMERASE

6. TRANSDIFFERENTIANTION-REPROGRAMMING

7. CELLULAR ORIGIN OF KIDNEY

8. RENAL STEM CELL
• In the developing organ, a nephron progenitor population gives rise to all of the
cellular components of the forming nephron.
• No such cell remains in the postnatal kidney.
• Formation of new nephrons after birth does not occur.

9. ORIGIN OF RENAL REPAIRING CELLS
Possible origins for cells contributing to postnatal renal repair:
• Interstitial cell transdifferentiation to epithelium
• Recruitment of cells from the bone marrow
• Tubular cell dedifferentiation and proliferation in response to injury
• Repopulation of the renal tubules by an adult resident kidney stem cells
• Human fetal kidney stem cells
• Cells from the amniotic fluid
• Directed differentiation of human PSCs (both embryonic stem cells [ESCs] and
induced pluripotent stem cells [iPSCs]) to kidney endpoints

10. Amniotic fluid-derived nephron progenitors
• Cultured cells from amniotic fluid are able to self-renew in a chromosomally
stable fashion for >350 doublings
• Collected between 12 and 18 weeks of gestation
• Injection of such cells into animal models of kidney disease delayed progression
of fibrosis
• These stem cells can generate in vitro into podocyte-like cells

11. INDUCED PSC
Any somatic cell can be returned to pluripotency [Dediferrentiation]; equivalent to an embryonic stem cell line.
The overexpression of 4 critical transcription factors are necessary :
- Oct3/4
- Sox2
- Klf14
- c-myc
Transcription factors for iPSC ---> Renal tissue[Redifferentiation] :
- BMP7
- Wnt agonist
- Activin A

12. INDUCED PSC

13. IPSC

14. RENAL STEM CELL
1. Bowman’s capsule
2. Renal papilla
3. Nephron tubules.

15. RENAL STEM CELL- BOWMAN’S CAPSULE
The Bowman’s capsule contains a subset of parietal epithelial cells (PECs) that are source of adult stem cells in the
kidney.
Co-express the common stem cell marker CD133 and the renal embryonic cell marker CD24 : Adult parietal
epithelial multipotent progenitors (APEMP)
APEMP :
- negative for the podocyte markers PDX, nephrin, podocin, synaptopodin, WT-1
- negative for the tubule marker EMA-1, THG
APEMP cells occasionally present in urine and
can be cultured into usable numbers.

16. RENAL STEM CELL- BOWMAN’S CAPSULE
APEMP cells when move towards to the vascular pole they first acquire the podocyte marker PDX followed by
loss of the stem cell markers CD24 and CD133 which corresponds to a loss of self-renewing and differentiation
capabilities.
APEMP cells :
- proximal and distal tubule cells
- podocytes
- non-renal differentiation:
- osteogenic
- adipogenic
- neurogenic

17. RENAL STEM CELL- BOWMAN’S CAPSULE

18. Renal stem cells in the papilla
• The renal papilla is unique in the kidney because of its hypoxic and
hyperosmotic environment.
• Adult stem cell population resides in an hypoxic environment.
• Renal papillary stem cell: CD 133+/ nestin +
• Hypoxia-- increases Oct4a expression and downregulates miR-145

19. Renal stem cells in the papilla
• FUNCTIONS:
- normal maintenance of the nearby tubules and collecting ducts
- respond to renal ischemic injury
• Nestin-positive cells migrate toward the base of the papilla and begin dividing
in response to ischemia
• Can be differentiated into tubulogenic and neurogenic lineages

20. Renal stem cells in the papilla

21. Renal tubular stem cell
LOCATION:
S1 TO S3, but most well studied in S3
Marker:
S1: CD133+/CD24+/CD106- [ PEC stem cell- CD133+/CD24+/CD106+]
S3: CD133+/CD24+/ALDH+

22. Renal tubular regeneration

23. Renal tubular regeneration

25. OPTIONS FOR RENAL REGENERATION

26. De Novo Organ Regeneration
1. Organ Regeneration Using Bioengineered Scaffolding.
2. Organ Regeneration Using Decellularized Cadaveric Scaffolds.
3. De Novo Organ Regeneration Using Blastocyst Complementation.
4. De Novo Organ Regeneration Using the Metanephros of Growing
Xenoembryos

27. Organ Regeneration Using Bioengineered Scaffolding.
• Advances in biomaterial engineering have produced bioengineered scaffolds that facilitate
improved differentiation of transplanted cells.
• Tissue-engineering strategies combining artificial scaffolds and stem cells have been
adapted for kidney regeneration.
• Histocompatible functional kidney was generated by using a specialized polymer tube as
the artificial scaffold

28. Organ Regeneration Using Bioengineered Scaffolding

29. Organ Regeneration Using Decellularized Cadaveric Scaffolds
Decellularized organ can be useful as an artificial scaffold. The decellularization
process preserves the structural and functional characteristics of the native
microvascular network.
- After decellularization of an intact kidney  ES cells were injected into the
renal artery where they localized in the vasculature, glomeruli and tubules.
- Immunohistochemical analysis indicated that the injected ES cells had lost
their embryonic appearance and had developed to mature kidney cell.

30. Organ Regeneration Using Decellularized Cadaveric Scaffolds

31. De Novo Organ Regeneration Using Blastocyst Complementation
• Blastocyst complementation system was recently applied to whole kidney reconstruction.
• Murine iPS cells were injected into blastocysts from mice that did not express
the SAL-like 1 (Sall1) zinc-finger nuclear factor essential for kidney development.
• The newborn mice possessed kidneys derived almost entirely of injected iPS cells
• To generate xenoorgan using xenoblastocysts it would be necessary to generate a host
animal strain lacking all of the lineages that contribute to the kidney

32. De Novo Organ Regeneration Using Blastocyst Complementation

33. Organ Regeneration Using the Metanephros of Growing Xenoembryo
• The embryonic metanephros is a primordium of the adult mammalian kidney and
represents a source for a transplantable kidney.
• Metanephroi implanted into a host renal cortex or omentum continue to develop and
enlarge. The differentiated metanephroi in the host have vascularized glomeruli and mature
proximal tubules and produce urine.
• The transplanted metanephros is also metabolically functional and produces Epo and renin.

34. Organ Regeneration Using the Metanephros of Growing Xenoembryo

35. NEPHROTOXICITY SCREENING
iPSC-derived kidney cells for the screening of drugs to evaluate
nephrotoxicity.
Toxicity monitoring by:
- Specific proximal tubular apoptosis
- Increased production of Kim1 protein

36. Mesenchymal stem cells
MSC are a specialised subset of nonhaematopoietic cells defined by capabilities of self-
renewal and differentiation into the mesodermal lineage
Location:
- bone marrow
- fetal amniotic fluid, placenta, umbilical cord, adipose tissue, endometrium,
bone, lung, liver
- kidney [perivascular, involved in normal tissue repair]

37. Mesenchymal stem cells
Therapeutic potential of MSC in AKI and CKD :
- this is not due to integration into the damaged epithelium or
transdifferentiation into an epithelial cell type.
- immunomodulatory capacity
- release of paracrine factors [HGF, IGF1, VEGF, EGF]
Concern with MSC:
In chronic renal insult, MSCs may maldifferentiate into adipocyte within the
glomeruli

38. Mesenchymal stem cells

40. BIOARTIFICIAL KIDNEY

41. BIOARTIFICIAL KIDNEY