The document discusses totipotency, which is the ability of a cell to differentiate into any type of cell and give rise to a whole new organism. Totipotent stem cells found early in embryo development can generate all 220 cell types in the body. As the embryo develops, most cells lose their totipotency. While totipotent stem cells could be useful for regenerative medicine, their use raises ethical issues due to their ability to form a complete organism. The document contrasts totipotent stem cells with pluripotent and multipotent stem cells, which can generate fewer cell types.

1. Totipotency
PRESENTATION BY
SHAIKH FAVZUL AZIM
BSC BIOCHEMISTRY SEMESTER – V
PARUL INSTITUTE OF APPLIED SCIENCES, PARUL UNIVERSITY,
VADODARA, GUJARAT
GUIDED BY
MRS SANSKRITI UPADHAYAY;
ASSISTANT PROFESSOR; PARUL INSTITUTE OF APPLIED SCIENCES,
PARUL UNIVERSITY; VADODARA, GUJARAT
Date of presentation
26/08/2020

2. Totipotency
 The cell’s ability to differentiate into any kind of cells which constitute the body
 In short, Totipotent stem cells (which exhibit totipotency) can give rise to a whole
new organism.
 Note: not all stem cells are totipotent
 These cell can give rise to any somatic as well as germ cell in the body.
 Most of the cells lose their totipotency after embryo is developed.
 Totipotent stem cells can give rise to 220 types of the cells in vertebrate’s body
 The use of totipotent stem cells (induced stem cells) in regenerative medicine is
ethically controversial subject.

3. Totipotent Pluripotent Multipotent
Relative potency High Medium Low
Cell types capable of
generating
Differentiate into any cell
type
Differentiate into cells
from any of the three
germ layers
Differentiate into a
limited range of cell types
Terminology Toti = Whole Pluri = Many Multi = Several
Examples Zygote, early morula Embryonic stem cells,
Induced pluripotent stem
cells
Haematopoietic stem
cells, neural stem cells,
mesenchymal stem cells
Found Early cells of fertilised eggInner mass cells of the
blastocyst
In many tissues
Expression of
pluripotency genes
+++ ++ +
Expression of lineage-
specific genes
+ ++ +++
Pros of use in research Easy to isolate and grow Easy to isolate and grow Less ethical issues, less
chance of immune
rejection if taken from
same patient
Cons of use in research Ethical issues Ethical issues, teratoma
formation
Hard to isolate, limited
differentiation, scarce

4. Totipotency
Example:
 Totipotent cell : Early embryonic cell (can give rise to any 220 cell type)
 Pluripotent cell : Cells forming mesoderm (can give rise to restricted linages of
cells such as muscle cells and blood cells)
 Multipotent cell : Stem cells of Cardiac muscle cell or hematopoietic stem cells
(which can only give rise to different types of same linage cells)
Characteristics of totipotent stem cells:
 Self regeneration
 High proliferation rate
 Has ability to undergo organogenesis under given circumstances (induced by
cytokines and other growth factors [in vivo as well as in vitro].