Trichinella spiralis: Inhibition of Muscle Larva Growth and Development Is Associated with a Delay in Expression of Infected Skeletal Muscle Characteristics

Trichinella spiralis : induction of the basophilic transformation of muscle cells by synchronous newborn larvae

“…However, it has been proven that muscle cells infected intramuscularly with irradiated NBL were transformed and that the nurse cell-muscle larva complex was thus formed. Nevertheless, the irradiation causes the inhibition of a-and b-stichocyte development (Jasmer and Neary 1994). This evidence shows that E/S products originating from the stichosome are not required for nurse cell formation.…”

“…(Kozek and Crandall 1974) in intramuscular infection. Other data demonstrate that intramuscular infection with irradiated NBL results in fully expressed nurse cells, despite the observation that irradiation inhibits stichosome development (Jasmer and Neary 1994). These data apply to all stichosome-derived E/S products, including the 43-kDa ES protein (p43).…”

“…Due to the high af®nity of sarcoplasm for alkaline dyes this process is referred to as basophilic transformation Gustowska 1967, 1970;Gabryel et al 1995). However, recently, dierent names with reference to the same process have also been used, including reorganization (Lee et al 1991), host cell-cycle reentry (Jasmer and Neary 1994), and dedierentiation (Vassilatis et al 1996). Basophilic transformation proceeds as a twophase process involving (a) the initial changes, mainly, occurring in myonuclei, and (b) the complete transformation alterations in myonuclei and sarcoplasm.…”

Identification and characterisation of a cDNA sequence encoding a glutamic acid-rich protein specifically transcribed in Trichinella spiralis newborn larvae and recognised by infected swine serum

“…Except for the short time following extrusion from the female, larvae are confined to the skeletal muscle cell. In general, successful infection of the muscle cell is paralleled by rapid changes in other cellular events that invoke a reprogramming of the cell, also referred to as basophilic transformation (Gabryel and Gustowska, 1970), host cell-cycle re-entry (Jasmer and Neary, 1994) and dedifferentiation (Vassilatis et al, 1996). Cell reprogramming is accompanied by DNA replication (Jasmer, 1993), enlargement and migration of infected cell nuclei (Despommier et al, 1991), reduction in myofibrillar proteins (Jasmer et al, 1990), termination of the host cell development in the G 2 /M phase with cessation of muscle gene transcription (Jasmer, 1993), and formation of a collagen-based envelope or cyst wall, around the cell.…”

“…In addition, Trichinella spiralis muscle larvae have garnered interest from investigators because of the strong host immune responses that develop as a consequence of antigens secreted from this stage. It had been postulated that the muscle larval ES antigens were responsible for reprogramming infected striated muscle cells; however, evidence has been advanced indicating that it is the newborn larvae that initiate these cellular events (Jasmer and Neary, 1994;Gabryel et al, 1995). Wranicz et al (1998) showed further that the genesis of cellular reprogramming can occur within muscle cells that do not directly contact newborn larvae but are proximal to those recently infected with Trichinella, suggesting that secretions from the newborn larvae present within the local milieu surrounding the newly infected cell are capable of inducing changes in the adjacent cells as well.…”