Aim: To investigate the effect of cryopreservation on the plasma membrane integrity in the head and tail regions ofindividual sperm, and the relationship between intact cryopreserved sperm and its motility and zona-fr...Aim: To investigate the effect of cryopreservation on the plasma membrane integrity in the head and tail regions ofindividual sperm, and the relationship between intact cryopreserved sperm and its motility and zona-free hamster oocytepenetration rate. Methods: The eosin Y exclusion and the hypoosmotic swelling tests were combined to form a sin-gle test (HOS-EY test) to identify the spermatozoa with four types of membrane integrity. Results: After cryop-reservation, there was a marked decline in the percentage of spermatozoa with Type Ⅳ membrane integrity (head mem-brane intact/tail membrane intact), and a significant increase in those with Type Ⅰ (head membrane damaged/tail mem-brane damaged) and Type Ⅲ (head membrane damaged/tail membrane intact) membrane integrity (n = 50, P <0.01). The value of Type Ⅲ integrity had a wide range of variability, whereas Type Ⅱ (head membrane intact/tailmembrane damaged) was uncommon after thawing. A high correlation was observed between the percentage of Type Ⅳintegrity and sperm motility ( n = 50, r = 0.74, P < 0.01 ). However, the values of Type Ⅳ integrity were usuallylower than those of post-thaw motility in most cryopreserved samples. The value of Type Ⅳ integrity did not correlatewith the sperm penetration rate ( n = 25, r = 0.22, P > 0.05). Conclusion: (1) The HOS-EY test has the advan-tage of showing four patterns of membrane integrity in individual spermatozoon; (2) Cryopreservation causes a signifi-cant membrane rupture in the head and tail regions of spermatozoa; Type Ⅲ is the main transitional state of membranecryodamage; (3) Cryodamage to head and tail membrane may occur independently; the presence of an intact tail mem-brane does not necessarily indicate the intacmess of head membrane. (4) Intact membranes are closely related to post-thaw motility, but do not reflect the fertilizing potential.展开更多
Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a p...Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease.However,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche.Here,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells.These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in vitro.Importantly,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts.Overall,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.展开更多
文摘Aim: To investigate the effect of cryopreservation on the plasma membrane integrity in the head and tail regions ofindividual sperm, and the relationship between intact cryopreserved sperm and its motility and zona-free hamster oocytepenetration rate. Methods: The eosin Y exclusion and the hypoosmotic swelling tests were combined to form a sin-gle test (HOS-EY test) to identify the spermatozoa with four types of membrane integrity. Results: After cryop-reservation, there was a marked decline in the percentage of spermatozoa with Type Ⅳ membrane integrity (head mem-brane intact/tail membrane intact), and a significant increase in those with Type Ⅰ (head membrane damaged/tail mem-brane damaged) and Type Ⅲ (head membrane damaged/tail membrane intact) membrane integrity (n = 50, P <0.01). The value of Type Ⅲ integrity had a wide range of variability, whereas Type Ⅱ (head membrane intact/tailmembrane damaged) was uncommon after thawing. A high correlation was observed between the percentage of Type Ⅳintegrity and sperm motility ( n = 50, r = 0.74, P < 0.01 ). However, the values of Type Ⅳ integrity were usuallylower than those of post-thaw motility in most cryopreserved samples. The value of Type Ⅳ integrity did not correlatewith the sperm penetration rate ( n = 25, r = 0.22, P > 0.05). Conclusion: (1) The HOS-EY test has the advan-tage of showing four patterns of membrane integrity in individual spermatozoon; (2) Cryopreservation causes a signifi-cant membrane rupture in the head and tail regions of spermatozoa; Type Ⅲ is the main transitional state of membranecryodamage; (3) Cryodamage to head and tail membrane may occur independently; the presence of an intact tail mem-brane does not necessarily indicate the intacmess of head membrane. (4) Intact membranes are closely related to post-thaw motility, but do not reflect the fertilizing potential.
基金supported by the National Key Research and Development Program of China,Nos.2017YFE0122900(to BH),2019YFA0110800(to WL),2019YFA0903802(to YW),2021YFA1101604(to LW),2018YFA0108502(to LF),and 2020YFA0804003(to JW)the National Natural Science Foundation of China,Nos.31621004(to WL,BH)and 31970821(to YW)+1 种基金CAS Project for Young Scientists in Basic Research,No.YSBR-041(to YW)Joint Funds of the National Natural Science Foundation of China,No.U21A20396(to BH)。
文摘Numerous studies have shown that cell replacement therapy can replenish lost cells and rebuild neural circuitry in animal models of Parkinson’s disease.Transplantation of midbrain dopaminergic progenitor cells is a promising treatment for Parkinson’s disease.However,transplanted cells can be injured by mechanical damage during handling and by changes in the transplantation niche.Here,we developed a one-step biomanufacturing platform that uses small-aperture gelatin microcarriers to produce beads carrying midbrain dopaminergic progenitor cells.These beads allow midbrain dopaminergic progenitor cell differentiation and cryopreservation without digestion,effectively maintaining axonal integrity in vitro.Importantly,midbrain dopaminergic progenitor cell bead grafts showed increased survival and only mild immunoreactivity in vivo compared with suspended midbrain dopaminergic progenitor cell grafts.Overall,our findings show that these midbrain dopaminergic progenitor cell beads enhance the effectiveness of neuronal cell transplantation.
