Conventional IVF: Differences between human and mouse models

2. INTRODUCTION
DEFINITION:
In vitro fertilisation (IVF) is a process by which
an egg is fertilised by sperm outside the body:
in vitro.
Evolved as a major treatment protocol for
infertility.
STEPS IN THE IVF CYCLE:
 Initial evaluation & suppression of natural
hormonal cycle
 Ovarian stimulation
 Collection of oocyte
 Collection of sperms
 In-vitro fertilization & embryo development
 Embryo transfer.

3. SPERMATOZOA
 Mouse has the longest sperm relative to its body weight. House mouse sperm
length is 124 micrometers.
 Length of human sperm: 50 micrometers.
 Morphological difference between human & mouse sperm includes sperm
head shapes, length of the sperm.
MOUSE SPERM MORPHOLOGY

4. MOUSE HUMAN
Induce superovulation by injecting
pregnant mare's serum gonadotropin
(PMSG) i.p. into 8-12 weeks old
mature female mouse.
After 48-52 hours, i.p. injection of
human chorionic gonadotropin (hCG)
is given.
•OOCYTE SIZE: 60µm -120µm
Typical protocol for ovarian
stimulation:
GnRH agonist/FSH – long down
regulation protocol.
GnRH agonist/FSH – short protocol.
Clomiphene citrate/ HMG
TRIGGER SHOT:
human chorionic gonadotropin
(hCG)
OOCYTE SIZE: 150µm - 180µm
OVARIAN STIMULATION

5. OOCYTE COLLECTION
MOUSE HUMAN
The female mouse was euthanized ,15-
17 hrs after hCG administration.
The oviducts were removed and placed
inside liquid paraffin within a fertilization
dish.
The ampulla is tear open and the
cumulus-oocyte complexes (COCs) were
releases from within.
Place them in the CARD medium.
Incubated at 37°C (5% CO2) for 30-
60mins before insemination.
 The oocyte retrieval is performed
usually between 34 -36 hrs after hCG
injection.
Oocyte retrieval is usually accomplished
by transvaginal ultrasound aspiration.
In some circumstances, one or both
ovaries may not be accessible by
transvaginal ultrasound, Laparoscopy may
then be used to retrieve the eggs.
COCs used for IVF were individually
cultured in 25 μl droplets of B2 medium
under paraffin oil.

6. COLLECTION OF SPERMATOZOA
MOUSE HUMAN
1.STANDARD PROCEDURE:
•Mature male mice were euthanized and
their cauda epididymides was removed.
•The sperms were stripped from cauda
epididymides.
2. NON TERMINAL PROCEDURES:
•Electroejaculation
•The injection of drugs
•Flushing the uterus of females previously
mated with target male.
3. INVASIVE METHODS:
PESA, MESA (Incase of sperm
compromised animals)
The sperm sample is incubated at 37°C
(5% CO2) for 60 mins.
1. EJACULATION:
Semen sample is provide by ejaculation
either by masturbation or through sexual
intercourse using special condoms.
2. INVASIVE METHODS:
Testicular sperm aspiration (TESA)
Percutaneous epididymal sperm
aspiration (PESA)
3.SPERM DONATION

7. MOUSE HUMAN
Bovine serum albumin is
typically used for in vitro animal
studies.
Tyrode's albumin lactate
pyruvate (TALP) medium is
typically used as a base, which
contains Bicarbonate & CaCl2.
Human serum albumin (HSA) is
used in human sperm
capacitation induction.
Human tubal fluid (HTF) is used
as a base, which contains
Bicarbonate & CaCl2
 CAPACITATION OF SPERMATOZOA
Assisted reproductive technologies, IVF & IUI require the induction of sperm
cell capacitation outside of normal biological parameters.
Capacitation can then be induced by adding media designed to mimic the
electrolytic composition of the fallopian tubes, where fertilization occurs

8. INSEMINATION & EMBRYO
DEVELOPMENT
MOUSE HUMAN
The formation if pro-nuclei is
observed after 3-4 hours post
insemination.
The 2 cell stage embryo is
observed after 17-18 hours post
fertilization.
The formation if pro-nuclei is
observed after 3-10 hours post
insemination.
The 2 cell stage embryo is
observed after 25-33 hours post
fertilization.

9. EMBRYO TRANSFER
MOUSE HUMAN
The embryo is
transferred to the
oviduct of the
pseudopregnant
female mouse.
Embryo is
transferred at
blastocyst stage to
the uterine wall.
EMBRYO TRANSFER IN HUMAN

10. REFERENCES
 Sadeghzadeh Oskouei B, Pashaiasl M, Heidari MH, et al. Evaluation of Mouse Oocyte In
Vitro Maturation Developmental Competency in Dynamic Culture Systems by Design and
Construction of A Lab on A Chip Device and Its Comparison with Conventional Culture
System. Cell J. 2016;18(2):205–213.
 E. Neuber, R.D. Powers, Is the mouse a clinically relevant model for human fertilization
failures?, Human Reproduction, Volume 15, Issue 1, January 2000, Pages 171–174
 Nazari S, Khalili MA, Esmaielzadeh F, Mohsenzadeh M. Maturation capacity, morphology
and morphometric assessment of human immature oocytes after vitrification and in-vitro
maturation. Iran J Reprod Med. 2011;9(3):209–216.
 Boersma A, Olszanska O, Walter I, Rülicke T. Microsurgical and Percutaneous
Epididymal Sperm Aspiration for Sperm Collection from Live Mice. J Am Assoc Lab Anim
Sci. 2015;54(5):471–477.