Human sperm pattern of movement during chemotactic re-orientation towards a progesterone source

Abstract

Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules. Although human spermatozoa have been observed to show several of the physiological characteristics of chemotaxis, the chemotactic pattern of movement has not been easy to describe. However, it is apparent that chemotactic cells may be identified while returning to the attractant source. This study characterizes the pattern of movement of human spermatozoa during chemotactic re-orientation towards a progesterone source, which is a physiological attractant candidate. By means of videomicroscopy and image analysis, a chemotactic pattern of movement was identified as the spermatozoon returned towards the source of a chemotactic concentration of progesterone (10 pmol l 21 ). First, as a continuation of its original path, the spermatozoon swims away from the progesterone source with linear movement and then turns back with a transitional movement that can be characterized by an increased velocity and decreased linearity. This sperm behaviour may help the spermatozoon to re-orient itself towards a progesterone source and may be used to identify the few cells that are undergoing chemotaxis at a given time.

Differential concentration and time dependent effects of progesterone on kinase activity, hyperactivation and acrosome reaction in human spermatozoa

“…, 2009), alter the flagellar beat patterns (Harper et al. , 2004), sense the cumulus and orient in a field (Blengini et al. , 2011) and induce motility (present study).…”

“…, 2006; Oren‐Benaroya et al. , 2008; Blengini et al. , 2011), they are not capable of inducing hyperactivation and acrosome reaction.…”

“…, 2006; Oren‐Benaroya et al. , 2008; Blengini et al. , 2011) and also increase the levels of intracellular calcium (Teves et al.…”

Possible ability of bovine follicular fluid to attract migrating bull spermatozoa

“…In the human,16, 21, 22, 23 rabbit,10 and mouse,15 sperm chemotaxis to the follicular fluid and egg‐related material has been observed, but the mechanism of sperm chemotaxis is not sufficiently understood. In this study, it was investigated whether bull sperm can be attracted to the BFF.…”

Microfluidics for Sperm Selection

“…Cumulus cells secrete progesterone after ovulation, and human sperm respond to picomolar concentrations of this hormone [ 45 ]. These responses include redirection of sperm movement in vitro if the progesterone source is repositioned in the culture dish [ 46 ], and migration through microchannels towards the source of progesterone and accumulation in the vessels containing progesterone [ 47 ].…”