Ultrastructural analysis of five patients with total sperm immotility

Abstract

Asthenozoospermia has been related to structural defects of the sperm flagellum. However, few reports have studied in detail the ultrastructure of sperm with total immotility. We present an ultrastructural study of sperm from five patients with total sperm immotility, four due to dysplasia of the fibrous sheath (DFS) and one with situs-inversus. Of the four patients with DFS, three cases presented a hypertrophic and hyperplastic fibrous sheath that invaded the midpiece space, absence of the annulus, and a short midpiece containing a few disorganized and pale mitochondria. Of these cases, two presented absence of the central complex and radial spokes; another additionally presented absence of dynein arms and nexin bridges; and the other patient presented an intact annulus with a dysplastic fibrous sheath restricted to the principal piece with disorganized microtubule doublets. The patient with situs-inversus presented severe respiratory symptoms, with absence of dynein arms and nexin bridges. In conclusion, we present three cases with DFS associated with total sperm immotility, abnormal mitochondria, and absence of the annulus, central pair complex and radial spokes, of which one had in addition absence of dynein arms and nexin bridges. We also describe a patient, with total sperm immotility and a different presentation of DFS, as the annulus was present and the dysplastic fibrous sheath was restricted to the principal piece. These findings thus confirm the heterogeneity of the DFS condition. The changes observed in the patient with situs-inversus also further support previous observations.

The importance of transmission electron microscopy analysis of spermatozoa: Diagnostic applications and basic research

“…A different type of this syndrome includes the presence of the annulus and the dysplastic fibrous sheath restricted to the principal piece. These observations may suggest heterogeneity of the DFS condition [Sousa et al 2015]. The genetic origin of the defect is suggested by familial incidence of DFS.…”

“…Globozoospermia or round head acrosome-less spermatozoa [Schirren et al 1971;Larson et al 2001], miniacrosome [Baccetti et al 1991], and a rare situation named 'crater defect' [Baccetti et al 1989] are all systematic defects of the sperm head. Defects of head neck attachment and acephalic sperm [Baccetti et al 1984;Chemes et al 1987a;Kamal et al 1999;Chemes and Rawe 2003], dysplasia of fibrous sheath (DFS) [Chemes et al 1987b;Chemes et al 1998;Sousa et al 2015], and primary ciliary dyskinesia (PCD) [Afzelius 1976;Escalier and David 1984;Chemes et al 1990;Baccetti et al 1993] are systematic defects of the head-neck attachment region and tail.…”

Major regulatory mechanisms involved in sperm motility

“…It is also frequent to observe absence of the central pair complex and dynein arms (DA) ( Figure 5 ). 106107 It has been estimated that about 20% of DFS cases have a familiar incidence and family tree analysis seems to indicate an autosomic recessive inheritance 108109. However, there are no consensus if DFS is a genetic disorder.…”

“…Absence or dislocation of the central pair complex, defects of radial spokes, and doublet abnormalities are also common. In about 50% of PCD cases, patients present Kartagener syndrome, which is characterized by the combination of situs inversus 106107. Therefore, investigations into the genetic basis of PCD have started by analysis of DA proteins 113.…”

Sperm with fibrous sheath dysplasia and anomalies in head-neck junction: focus on centriole and centrin 1

“…By these methods, systematic sperm defects have been characterised and categorised as alterations of sperm head such as globozoospermia (Chansel‐Debordeaux et al, ; Dam et al., ) or of sperm tail as primary ciliary dyskinesia (PCD, Afzelius, ; Chemes et al ; Moretti et al., ), dysplasia of the fibrous sheath (DFS, Chemes et al. , , ; Rawe et al, ; Sousa et al., ) and of head–neck attachment such as the decapitated sperm defect (Chemes & Rawe, ; Kamal et al., ; Rawe et al., ).…”