Sperm Function Tests are the keystones of evaluating functional condition of sperms. The fertility potential of a sperm will be decided not only with the number & motility but with the functional competence which is of utmost importance.
2. sperm is a male reproductive cell, which is motile.
It is 60µm long and 2-5µm wide and contains 23 set
of chromosomes
3. ATTRIBUTES OF NORMAL SPERMATOZOA
1-Plasma membrane
2-Outer acrosomal membrane
3-Acrosome
4-Inner acrosomal membrane
5-Nucleus
6-Proximal centriole
7-Rest of the distal centriole
8-Thick outer longitudinal
fibers
9-Mitochondrion
10-Axoneme
11-Anulus
12-Ring fibers
A-Head, B-Neck, C-Mid
piece, D-Principal piece, E-
End piece
• TO EXHIBIT A NORMAL STRUCTURE
• PERSISTS MOTILE MOVEMENTS TO PASS THROUGH REPRODUCTIVE TRACT BARRIERS
• PROPERLY PACKAGED AND STABLE DNA
• MAINTAIN FUNCTIONAL METABOLIC PATHWAYS (RECEPTOR PROTIENS,
ACROSOMAL ENZYMES, SURVIVAL PROTEINS TO MAINTAIN IN FEMALE TRACT )
4. SFTs are the keystones of male
infertility evaluation
“In vivo” and “in vitro” conditions
sperm functions are same
The fertility will be decided not
only with the number but also the
functional competence of sperms
5. SPERM FUNCTION TESTS
Semen analysis is an essential component when
assessing male reproductive capacity
Semen analysis incompletely provides a
comprehensive assessment of male fertility potential
Sperm function tests adds important data regarding
sperm ability for fertilization and impact in post
embryo development
Use of SFT in conjunction with semen analysis
contributes more efficient treatment strategy
6. SO, WHAT ARE SPERM FUNCTIONS?
TO BE PRESENT IN AN EJACULATE ?
TO BE IN A GOOD NUMBER?
TO BE MOTILE ?
HAVE A GOOD MOTILE SPEED?
NAAAAAAAAAHHHHHHHH…….
7. SPERM FUNCTIONS ARE
TO FERTILIZE AN OOCYTE
DELIVER INTACT DNA INTO OOCYTE
ACHIEVE HEALTHY PREGNANCY
8. Advent of sperm function tests
Patient demand derived innovation
Patient satisfactory treatment approaches
Detailed assessment in Sperm assessments to rule
out cause
Translation of benchtop to bedside
9. SPERM FUNCTIONS
BASIC FUNCTION IS TO FERTILIZE AN OVUM AND
CONTRIBUTES CHROMOSOMES
sperm functions including their potential for movement, cervical
mucus penetration,
capacitation, zona recognition, the acrosome reaction and
sperm-oocyte fusion
19. Motility
Microscopic examination
Computer assisted semen analyzers (CASA)
Advantages
High accuracy
Quantitative information on the kinematic parameters of
spermatozoa (forward progression and hyper activated
motility, characteristic of capacitated cells)
Utility
Productivity of testis
Patency of GT
Substantial motility reveals severe infection and
inflammatory reactions in RT
Abnormal sequence of ejaculation
Disorders of sex glands
Correlated with DNA fragmentation
20. Eosin and Nigrosin Procedure
1- Mix 50µl of semen with 2 drops of eosin
2- mix 3 drops of Nigrosin after 30 seconds
3- Prepare a slide after 30 seconds and leave it for dry
4- examine immediately after drying with oil immersion at 100x
Utility
Progressive motility < 40%
LRL-58%
21. Hypo-Osmotic Swelling (HOS) test
Procedure
1- Incubate 1ml of HOS solution for 5-10 minutes
2- mix 0.1 ml of semen with HOS Solution and incubate
again for 30 minutes
3- Make a wet preparation with 10-15µls of incubated
sample
4- Examine at 40x
Utility
Discover active sperms
The sample can be reused
22. BIOCHEMICAL TESTS
Poor-quality semen may result from testicular production
of abnormal spermatozoa, or from post-testicular
damage to spermatozoa in the epididymis or the
ejaculate from abnormal accessory gland secretions.
Secretions from accessory glands can be measured to
assess gland function
An infection can sometimes cause a decrease in the
secretion of these markers, but the total amount of
markers present may still be within the normal range.
23. BIOCHEMICAL TESTS
The amount of zinc, citric acid (Möllering & Gruber, 1966) or acid
phosphatase (Heite & Wetterauer, 1979) in semen gives a reliable
measure of prostate gland secretion, and there are good
correlations between these markers.
Secretory capacity of the seminal vesicles. Fructose in semen reflects
the secretory function of the seminal vesicles.
Secretory capacity of the epididymis. L-Carnitine, GPC and neutral
–glucosidase are epididymal markers used clinically. Neutral -
glucosidase has been shown to be more specific and sensitive for
epididymal disorders than L-carnitine and GPC (Cooper et al.,
1990a).
There are two isoforms of –glucosidase in the seminal plasma: the
major, neutral form originates solely from the epididymis, and the
minor, acidic form, mainly from the prostate.
24. MEASUREMENT OF ZINC
Spectrophotometric Assay
The volumes of semen and reagents can be
proportionally adjusted for spectrophotometers
using 3-ml or 1-ml cuvettes.
The lower reference limit for zinc is 2.4 mol per
ejaculate (Cooper et al., 1991 and unpublished
data from TG Cooper).
25. MEASUREMENT OF FRUCTOSE
Fructose is an energy source for sperm motility,
Azoospermia negative fructose results may indicate
absence of SV/VD or any obstruction
Can be assessed via both ways qualitative &
quantitative
Quantitatively,
The lower reference limit for fructose is 13 mol per
ejaculate
26. MEASUREMENT OF FRUCTOSE
Fructose testing should be considered for patients
with azoospermia, low volumes
Determined by heating semen in a strong acid in the
presence of resorcinol. Fructose gives red color
upon heating.
Low fructose in semen is characteristic of ejaculatory
duct obstruction, bilateral congenital absence of the
vas deferens
27. MEASUREMENT OF GLUCOSIDASE
Seminal plasma contains both a neutral -glucosidase
isoenzyme, which originates in the epididymis, and
an acid isoenzyme contributed by the prostate.
The lower reference limit for neutral -glucosidase is
20 mU per ejaculate
28. CASA
(COMPUTER AIDED SEMEN ANALYSIS)
Until recently, it was not feasible to measure sperm
concentration by computer aided sperm analysis (CASA)
because of difficulties in distinguishing spermatozoa from
particulate debris (ESHRE, 1998).
Several manufacturers produce CASA systems. These
machines are capable of measuring sperm motility and
kinematics, and some can also be used to estimate sperm
concentration.
CASA, including assessment of motility, concentration and
morphology, has two advantages over manual methods: it
has high precision and it provides quantitative data on the
kinematic parameters of spermatozoa (forward progression,
hyperactive motility)
29. CASA
(COMPUTER AIDED SEMEN ANALYSIS)
Some studies have suggested that CASA estimates
of concentration and movement characteristics of
progressively motile spermatozoa are significantly
related to fertilization rates in vitro and in vivo, as
well as to time to conception
Many factors affect the performance of CASA
instruments, e.g. sample preparation, frame rate,
sperm concentration and counting-chamber depth
32. Sperm Antibodies
Because mature spermatozoa are formed after
puberty, they can be recognized as foreign protein by
the male immune system. If there is a breach in this so-
called “blood–testis barrier,”
These antibodies can then come into contact with the
sperm and may cause them to clump.
There are several tests currently employed for detecting
the presence of sperm antibodies.
The two most common are mixed agglutination
reaction (MAR) and the Immunobead binding test.
33. Mixed Agglutination Reaction (MAR)
This test is performed by mixing semen, IgG- or IgA-
coated latex beads or red blood cells, and IgG or IgA
antiserum on a microscope slide. The slides are
incubated and observed at 400× magnification. At
least 200 sperm are counted. If antibodies are present,
the sperm will form clumps with the coated latex beads
or coated red blood cells. If antibodies are absent, the
sperm will swim freely.
The WHO considers a level of binding of ≥50% to be
clinically significant. This test is used only for detection
of direct antibodies in men, and is not specific for the
location of bead attachment to the sperm.
34. The Immunobead Binding Test
This test is performed by combining IgG- or IgA-coated
latex beads and washed sperm on a slide. The sperm
must be removed from the seminal plasma by washing
the sample with media plus bovine serum albumin (BSA).
The presence of human protein on the surface of the
sperm interferes with the binding of the immunobeads
to the sperm, and thus may mask a positive result. After
washing, the sperm is placed on a slide with IgG- or
IgA-coated latex beads and is read at 200× or 400×
magnification. If antibodies are present, the small
beads will attach directly to the sperm.
The level of binding of ≥50% is commonly considered
to be clinically significant
35. SPERM ACROSOME
The acrosome is an intracellular organelle, similar to a
lysosome, which forms a cap-like structure over the
apical portion of the sperm nucleus (36). The acrosome
contains multiple hydrolytic enzymes, including
hyaluronidase, neuraminidase, proacrosin,
phospholipase, and acid phosphatase, which, when
released, are thought to facilitate sperm passage
through the cumulus mass, and possibly the zona
pellucida.
In fact, only acrosome-reacted sperm is capable of
penetrating the zona pellucida, binding to the
oolemma, and fusing with the oocyte
36. SPERM ACROSOME
This has led to the necessity for the development of
biochemical markers for the acrosome reaction.
Contemporary assays for the determination of
acrosomal status employ fluorescent plant lectins or
monoclonal antibodies, which can be detected much
more easily with fluorescence microscopy.
one of the predominant enzymes that is present in
the acrosome is proacrosin. The enzymatic action of
acrosin is not necessarily correlated to the presence
of an intact acrosome
37. HEMI-ZONA BINDING ASSAY
a significant correlation between tests of sperm–zona
pellucida binding and subsequent fertilization in ART
the hemizona assay (HZA) employs sperm and
nonviable oocytes in an in vitro assessment of
fertilization
This test assesses the ability of sperm to bind to the
zona itself. Although the HZA is relatively expensive,
labor intensive, and difficult to perform, there are some
data that suggest that the HZA may help to identify
individuals with a poor prognosis for success with ART
38. HEMIZONA BINDING ASSAY
oocytes that failed to fertilize during an ART
procedure are bisected, and then sperm from a
proven fertile donor (500,000/mL) is added to one
hemizona, while sperm from the subject male is
added to the other hemizona. Following a four-hour
incubation, each hemizona is removed and pipetted
in order to dislodge loosely attached sperm. A
comparison or hemizona index (HZI) is then
calculated
39. HEMI-ZONA BINDING ASSAY
Unlike several other tests of sperm function,
a cutoff value
(35%)
has been identified as a predictor of IVF success.
40. MANNOSE BINDING ASSAY
Another test has been developed in order to assess
the ability of sperm to bind to the zona.
involves the recognition by a sperm surface receptor
of a specific complementary receptor on the surface
of the zona pellucida.
This zona receptor appears to be a glycoprotein,
the predominant sugar moiety of which is mannose
In vitro assays in which labeled probes of mannose
conjugated to albumin are co-incubated with semen
specimens allow for the differential staining of
sperm
invites further study
42. PICSI- Physiological ICSI
In the process of fertilization, the sperm bind
to the hyaluronic acid (HA) present in the
cumulus oophorus by HspA2 protein, with
hyaluronidase activity that induces acrosome
reaction.
The PICSI device, a dish similar to ICSI dish,
contains microdots of hyaluronan hydrogel
which needs to be hydrated by media before
ICSI.
Selectively binding of sperm to the culture
dish shows:
More viability,
Non DNA-fragmented, and
with lower rates of aneuploidies.
43. Selection of HA binding spermatozoa
Incubation, RT, 10
min
Add sperm to the hyaluronan
microdot
Gentle aspiration of a bound
spermatozoa
After 15 min, the proportion of hyaluronan-bound spermatozoa, that exhibited vigorous tail
beating, were assessed versus the unbound motile spermatozoa
45. ASSAYS FOR SPERM DNA INTEGRITY
The most current area of investigation into sperm
function involves the assessment of sperm DNA
integrity
Sperm chromatin has been demonstrated to be
packaged very differently from chromatin in
somatic cells.
As there are many ways in which this DNA
organization or the sperm chromatin itself can be
damaged,
47. ASSAYS FOR SPERM DNA INTEGRITY
SPERM KARYOTYPING
SPERM FISH ANALYSIS
SPERM DNA FRAGMENTATION TESTS
48. INDICATIONS FOR SPERM DNA ASSESSMENT
Unexplained infertility
Repeated ART Failures
Recurrent Pregnancy Losses
Prediction of ART outcomes
Assessment of DNA/Genetic Integrity
- Post Chemotherapy
- Advanced Paternal Age
49. DETECTION OF SPERM DNA DAMAGE
Strand breaks in DNA
Strand breaks in DNA
Susceptibility to
Denaturation
50. OTHER TESTS FOR
DETECTION OF SPERM DNA DAMAGE
Strand breaks in DNA (incorporation of probes at site of damage)
DNA breakage detection FISH (DBD-FISH) (potential DNA damage)
In situ nick translation (ISNT) (real DNA damage)
8-Hydroxydeoxy-guanosine (8-OHdG) (real DNA damage)
Susceptibility to denaturation in an acidic solution
Halosperm test (potential DNA damage)
Chromatin condensation
Aniline blue stain
Toluidine blue stain
ChromomycinA3 stain
51. Sperm Chromatin Dispersion Assay
sperm are immersed in an agarose matrix on a slide,
treated with an acid solution to denature DNA that contains
breaks, and
then treated with lysis buffer to remove membranes and
proteins.
The agarose matrix allows working with unfixed sperm on a
slide in a suspension-like environment.
Removal of nuclear proteins results in nucleoids with a
central core and a peripheral halo of dispersed DNA loops.
Sperm nuclei with elevated DNA fragmentation produce
very small or no halos of DNA dispersion, whereas those
sperm with low levels of DNA fragmentation release their
DNA loops forming large halos.
53. SPERM CHROMATIN STRUCTURE ASSAY
The SCSA measures the level of DNA
fragmentation after denaturation by using
acridine orange staining and flow cytometry.
Double-stranded (native) DNA stains green
and single stranded (denatured) DNA stains
red.
SCSA also detects immature sperm that have
increased histones rather than protamines.
54. SPERM CHROMATIN STRUCTURE ASSAY
• SCSA is an accurate and
reproducible test for
measuring sperm DNA
damage
• Test requires a highly skilled
staff, expensive equipment
which limits its widespread
use
55. TUNEL Assay
(Terminal deoxytransferase-mediated dUTP nick end-labeling)
TUNEL is a direct method to detect single and
double strand breaks in the DNA
Detects DNA strand breaks resulting from apoptotic
signaling cascades
TUNEL can be used in a clinical setting using
flowcytometer.
56. TUNEL Assay
(Terminal deoxytransferase-mediated dUTP nick end-labeling)
This single-step staining method labels
DNA breaks with fluorescein
isothiocyanate (FITC)-dUTP followed
by flow cytometric analysis.
TUNEL utilizes a template-
independent DNA polymerase called
TdT which non-preferentially adds
deoxyribonucleotides to 3´-hydroxyl
(OH) single- and double-stranded
DNA.
dUTP is the substrate that is added
by the TdT enzyme to the free 3´-OH
break-ends of DNA
57. COMET Assay
Comet assay (single cell gel electrophoresis) commonly
used to detect extent of DNA damage in spermatozoa
with exposure to an electric field under neutral or
alkaline conditions
Damage is measured by measuring displacement
between genetic material of nucleus „comet head‟ and
resulting tail
58. COMET Assay
Embedding of sperm in agarose gel
Lysing of cells and decondensation of DNA
Unwinding of DNA
Separation and staining of DNA fragments
Image and statistical analysis
Quantifies actual damage in individual sperm
COMET images showing
1. Damaged
2. Undamaged DNA
59. UTILITY OF SDF TESTS
SDF is mainly oxidative stress mediated
Elevated SDF is associated with infertility, Poor ART
outcomes and recurrent miscarriages
SDF gives different information than routine semen
analysis and have better prognostic value
≤ 15% DFI EXCELLENT TO GOOD SPERM DNA INTEGRITY
> 15% TO < 25% GOOD TO FAIR SPERM DNA INEGRITY
≥ 25% TO <50% FAIR TO POOR SPERM DNA INEGRITY
≥ 50% VERY POOR SPERM DNA INEGRITY
63. Utilities of SFTs
Diagnosis of infertility
Selection of preparation
Selection of insemination method
Selection of sperms for Micromanipulation
Reduce embryonic development abnormalities
Give an overview of overall outcome