Atomic force microscopy: a powerful tool for high-resolution imaging of spermatozoa

Abstract

Atomic force microscopy (AFM) has emerged as the only technique capable of real-time imaging of the surface of a living cell at nano-resolution. Since AFM provides the advantage of directly observing living biological cells in their native environment, this technique has found many applications in pharmacology, biotechnology, microbiology, structural and molecular biology, genetics and other biology-related fields. AFM has also proved to be a valuable tool for reproductive biologists. An exhaustive review on the various applications of AFM to sperm cells is presented. AFM has been extensively applied for determining the structural and topological features of spermatozoa. Unstained, unfixed spermatozoa in their natural physiological surroundings can be imaged by this technique which provides valuable information about the morphological and pathological defects in sperm cells as three-dimensional images with precise topographical details. Sperm head defects and the acrosome at the tip of the head responsible for fertilization, can be examined and correlated with the lack of functional integrity of the cell. Considerable amount of work is reported on the structural details of the highly condensed chromatin in sperm head using AFM. Detailed information on 3D topographical images of spermatozoa acquired by AFM is expected to provide a better understanding of various reproductive pathways which, in turn, can facilitate improved infertility management and/or contraceptive development.

Nanoscale Differences in the Shape and Size of X and Y Chromosome-Bearing Bovine Sperm Heads Assessed by Atomic Force Microscopy

“…Assessment of the sperm cell by AFM provides topographic images, which can be viewed in 3D, allowing the observation of nanoscale details [15]. Moreover, AFM slides are prepared quickly and easily and under near-physiological conditions [25]. Although AFM imaging can be performed on living cells, a structural/temporal barrier prevents its use with live sperm cell due to the time spent to capture images from one single sample (∼10 min).…”

Ultra‐structural analysis of human spermatozoa by aperture scanning near‐field optical microscopy

“…For the characterization of sperm morphology, AFM has been demonstrated to be relevant to obtain highresolution 3D surface topography of fixed samples [21][22][23]. An AFM study of mammalian spermatozoa guided in understanding cell structure-function relationship, which is expected to have a significant application in human reproduction [24].…”

Atomic force microscopy correlates antimetastatic potentials of HepG2 cell line with its redox/energy status: effects of curcumin and Khaya senegalensis

“…[20,21] As the only technique capable of real-time imaging of the surface of living cells in their native environment, this technique has found many applications in pharmacology, biotechnology, microbiology, structural and molecular biology, genetics and other biology-related fields. [22] Through AFM nanomechanical analysis, our laboratory has demonstrated that cell elasticity is highly correlated with metastatic potential; AFM nanomechanical profiling also has potential applications as a marker for cancer drug sensitivity. [23,24]…”