These photos show DNA fragmentation in human sperm assessed by TUNEL assay. Plate A is a light photomicrograph of sperm smear and green sperm heads in plate B show damage to sperm DNA under fluoroscent microscopy.
This photo shows DNA damage to human sperm assessed by Acridine Orange staining. Green sperm heads show normal DNA while Yellow to Red sperm heads show damage to DNA.
This slide shows DNA fragmentation in human sperm determined by TUNEL assay counterstained by DAPI. Blue sperm heads show normal DNA while green sperm heads indicate DNA damage.
Fluorescence micrograph showing the chromosomes from developing sperm cells.
Nuclear transfer in Mouse Oocytes: (A)- lancing of zona pellucida, (B and C)- removal of germinal vesicle, (D)- an isolated germinal vesicle.
This photo shows a human blastocyst - an embryo 5-6 days old. This embryo is hatching out of its "shell" to the right. The shell, known as the zona pellucida, is visible as an almost transparent structure surrounding part of the embryo on the left.
These photos show human embryos that are 3 days old. Embryos are evaluated for "quality" to help decide which embryos to transfer. Embryo quality evaluations are based on the number of cells present in the embryo, the size and regularity of those cells and the degree of fragmentation observed. While Level 1 and Level 2 embryos are more likely to implant and result in a successful pregnancy, there is no evidence of increased abnormalities or birth defects associated with lower embryo quality levels.
Light photomicrograph of live rat sperm using differential interference contrast (DIC) microscopy. The hook shaped heads are all very similar, indicative of the low level of variability in morphology of rat sperm.
Light photomicrograph of human sperm cells stained with Hematoxylin and Eosin (H&E) for evaluation of morphology. Human sperm have a highly variable morphology (shape). Morphology is routinely used as a measure of fertility status; this micrograph shows several variations in head shape.
Transmission Electron Micrograph (TEM) of the sperm midpiece, this longitudinal section through a sperm shows the mitochondria where energy for the cell is produced, and the microtubule structure of the tail providing the ability of the sperm to swim through the reproductive tract of the female.
Transmission Electron Micrograph (TEM) of the sperm centrosome; the microtubule structure of the tail is easily visible at this high magnification. Notice the structured arrangement of the centrosome, a required organelle (a sub-cellular structure) for fertilization in humans.
Fluorescent micrograph of a blastomere (a single cell from a developing embryo) stained to detect chromosome abnormalities.
Small germinal vesicle stage mouse oocyte surrounded by cumulus cells just before it is to be impaled with a glass needle during an experiment investigating gene expression.
Small preantral follicle from a porcine ovary processed for brightfield histology. The mammalian oocyte is held in a quiescent state in the surrounding follicle until it begins to grow during the ovulatory cycle.
Scanning electron micrograph (SEM) of a round-headed sperm cell. Note the lack of the sperm acrosome, necessary for normal fertilization, which is consistent with round-headed sperm.
Transmission electron micrograph (TEM) of a round-headed sperm. The chromatin has not undergone complete condensation, and remnants of the cytoplasm remain. The sperm acrosome is absent, and the midpiece is abnormal.
Scanning electron micrograph of numerous sperm morphologies.
Intra-cytoplasmic sperm injection (ICSI). The sperm is visible in the tip of the needle just before it is expelled into position at four o'clock.
Transmission electron micrograph (TEM) of an abnormal sperm. The midpiece and tail show no organization of the microtubules or mitochondria. Swirling invaginations of the nuclear membrane are also visible.
Hamster egg with human sperm bound to the surface, and penetration of sperm into the cytoplasm. The sperm penetration assay (SPA) uses hamster eggs as a substitute to human eggs in order to measure the ability of a patient's sperm to undergo capacitation and penetration of an egg. This assay predicts the ability of the patient's sperm to fertilize human eggs. Penetrating sperm are identified by the swelling of the sperm head which occurs after penetration.
Fluorescent in-situ hybridization (FISH) of probes for chromosomes X, Y, 13, 18, and 21 to sperm DNA. This abnormal sperm has one X and 18 chromosomes, but two 13 and 21 chromosomes. The FISH procedure allows the laboratory to evaluate abnormal chromosome segregation during sperm development.
Co-culture of a human embryo with human granulosa/cumulus cells. Co-culture appears to benefit embryo growth by providing growth factors and/or removing embryo-toxic factors from the environment.
Embryo biopsy for preimplantation genetic diagnosis (PGD). A small hole is made in the zona pellucida using acidic tyrode's solution, then the blastomere is gently removed by suction.
Scanning electron micrograph of a round-headed sperm.
Transmission electron micrograph of the head and tail of an immature sperm cell with abundant cytoplasmic remnants and incomplete nuclear condensation.
Abnormal head and midpiece morphology of a round-headed sperm lacking an acrosome.
Transmission electron micrograph of cross sections of tails from three sperm. The 9+2 microtubule pattern is abnormal in the lower two cross-sections, and precludes normal sperm motility.
Fertilized human oocyte. Note the normal segregation of the nucleoli towards the center of the two pronuclei.
Three human embryos ready for transfer to the recipient. The embryos are 6, 8, and 10 cells, respectively.
Human blastocyst with the inner cell mass visible.
Human embryo with attached cumulus tissue.
Transmission electron micrograph (TEM) of a sperm with a relatively normal head morphology, but chaotic organization of the tail. The cytoplasm remains and is unorganized.
A. Light micrograph of a semen sample containing numerous round cells. B. The same semen sample is shown after staining with a peroxidase stain, which stains polymorphonuclear white blood cells.
Abnormal sperm head morphology revealed by transmission electron microscopy (TEM). Note the large vacuole containing abundant nuclear membrane swirling.
Penetration of human cervical mucus by human sperm. Penetration of the mucus is accomplished by the formation of "columns" of sperm which ultimately diffuse into the mucus.
Human sperm undergoing slight and severe chromatin decondensation following incubation in medium containing heparin sulfate. Chromatin decondensation is indicative of diminished semen quality and fertilizing ability.
Sperm analyzed by FISH. This sperm cell contains extra copies of chromosomes 13 and 21.
Flourescent micrograph of sperm stained with propidium iodide, red pisum sativum agglutinin (PSA), green. The PSA staining pattern is consistent with a sperm with an intact acrosome.
Fluorescent micrograph of sperm stained with propidium iodide red and PSA green. This staining pattern is consistent with acrosome-reacted sperm.