B. Cell-Matrix Interactions A How cells pull onto and deform the matrix to which they attach themselves B Cell-matrix interactions control the spontaneous closure of wounds in organs C. What happens when regeneration is induced?
B. Cell-Matrix Interactions A. How cells pull onto and deform the matrix to which they attach themselves. B. Cell-matrix interactions control the spontaneous closure of wounds in organs. C. What happens when regeneration is induced?
B. Cell-matrix interactions control the spontaneous closure of wounds in organs. 1. Hypothesis: Regeneration requires selective blocking of contraction. Need for understanding of kinetics and mechanism of contraction(to be tested later) 2. Initiation of contractile force, Defect perimeter or center of skin defect? 3. Propagation of contraction Do cells cooperate? 4. Termination of contraction How does the contractile force die out?
B. Cell-matrix interactions control the spontaneous closure of wounds in organs. 1. Hypothesis: Regeneration requires selective blocking of contraction. Need for understanding of kinetics and mechanism of contraction (to be tested later). 2. Initiation of contractile force. Defect perimeter or center of skin defect? 3. Propagation of contraction. Do cells cooperate? 4. Termination of contraction. How does the contractile force die out?
2 Initiation of contractile force Located at defect perimeter or uniformly distributed? Picture frame vs, uniform contractile field UCF)hypotheses Data in Fig. 9.2(attached) show that the ECM analog that blocks contraction is effective at perimeter but not at center of defect These data support the picture frame hy pothesis However, other data(Fig. 4.4) support the UCF hypothesis
2. Initiation of contractile force. Located at defect perimeter or uniformly distributed? • Picture frame vs. uniform contractile field (UCF) hypotheses. • Data in Fig. 9.2 (attached) show that the ECM analog that blocks contraction is effective at perimeter but not at center of defect. • These data support the picture frame hypothesis. • However, other data (Fig. 4.4) support the UCF hypothesis
Spontaneously contracting dermis-free defect (10 d) Contractile cells stained brown Two magnifications Image removed due to copyright considerations
Spontaneously contracting dermis-free defect (10 d). Contractile cells stained brown. Two magnifications. Image removed due to copyright considerations. Image removed due to copyright considerations
Contraction of dermis- free defect blocked by drt Image removed due to copyright considerations Brown, contractile cells. Blue-gray, porous DRT
Contraction of dermis-free defect blocked by DRT Brown, contractile cells. Blue-gray, porous DRT. Image removed due to copyright considerations