Germ Cell Development In The Postnatal Testis: The Key To Early Surgery To Prevent Infertility And Malignancy In Cryptorchidism
Funder
National Health and Medical Research Council
Funding Amount
$725,326.00
Summary
The germ cells have been studied very extensively before birth or after puberty, but little is known about what happens shortly after birth. In children with undescended testes, early germ cell development is deranged, and this may be the key to find the right time for surgery to prevent subsequent infertility and risk of cancer. This project proposes some novel hypotheses to explain this and the studies aim to obtain the evidence to support surgery in the first 3-6 months of life..
Developing In Vivo Methods Of Adipose Tissue Engineering
Funder
National Health and Medical Research Council
Funding Amount
$374,703.00
Summary
Surgical repair and replacement of soft tissues after tumour removal or to repair existing damage requires fat tissue with a good blood supply. Tissue engineering allows us to create new fat grafts for replacement tissue without causing unnecessary pain or trauma to the patient. We have developed a method for growing fat tissue using a chamber to maintain a space for the tissue to grow into, a blood vessel to supply nutrients to the growing tissue, cells or tissue from the host to encourage cell ....Surgical repair and replacement of soft tissues after tumour removal or to repair existing damage requires fat tissue with a good blood supply. Tissue engineering allows us to create new fat grafts for replacement tissue without causing unnecessary pain or trauma to the patient. We have developed a method for growing fat tissue using a chamber to maintain a space for the tissue to grow into, a blood vessel to supply nutrients to the growing tissue, cells or tissue from the host to encourage cell growth and migration and a matrix or scaffold to support the developing tissue and guide it to form the type of tissue we want (fat, muscle etc). We have shown that the tissue graft may cause fat to grow due to causing an inflammatory reaction and confirmed this by adding a mild inflammatory compound to the chamber instead of a tissue graft. This compound caused the chamber to grow fat tissue. The aim of this project is to determine which of the growth factors or other signaling factors released by the inflammation process is responsible for causing fat tissue production and to identify what cells are being attracted to the chamber to help grow the fat, so that we can further improve our engineering of fat tissue. Understanding the pathways which mediate or stimulate fat growth will provide new opportunities for improving fat growth and allow the engineering of larger fat grafts in larger animals and eventually human clinical application. Beyond that, inflammation is involved in many disease processes (eg. obesity, metabolic syndrome, diabetes, cancer), and these fields of study will also benefit from our research.Read moreRead less
Engineering Tissues And Organs In Vivo From Stem Cells
Funder
National Health and Medical Research Council
Funding Amount
$549,480.00
Summary
Tissue engineering is an exciting new area of medical research. We have developed a unique animal model of tissue engineering where new tissue spontaneously sprouts from the surface of a vascular loop enclosed inside a plastic chamber. The tissue thus created has its own blood supply. By adding cultured cells or altering the environment of the chamber we have been able to grow new specific tissues such as fat and muscle. This technology potentially allows the generation of spare body parts to re ....Tissue engineering is an exciting new area of medical research. We have developed a unique animal model of tissue engineering where new tissue spontaneously sprouts from the surface of a vascular loop enclosed inside a plastic chamber. The tissue thus created has its own blood supply. By adding cultured cells or altering the environment of the chamber we have been able to grow new specific tissues such as fat and muscle. This technology potentially allows the generation of spare body parts to replace lost or worn out organs and tissues. We have recently reproduced this model in the mouse to be able to screen a range of mouse and human stem cells. These cells have the ability to change (i.e. differentiate) into many different types of cell depending on how they are stimulated. In Part 1 of this project we will determine in the mouse chamber the growth characteristics and survival rates of these stem cells. A chamber encapsulating a flowing blood vessel will be implanted subcutaneously in each groin. In one chamber we will inject fluorescently labelled stem cells in a growth medium and in the other growth medium alone. Tissue will be analysed at 1, 2 and 4 weeks. In Part 2 we will inject a variety of Rosa26 labelled mouse stem cells obtained from several different tissues. Through the aid of naturally occurring growth and differentiation factors they will differentiate into one of several different tissues including fat, cartilage, bone, neural tissue, blood vessels, liver, etc, which will be identified by histology and cell culture. In one experiment we will genetically alter cells injected into the chamber so that they produce only skeletal muscle. In Part 3 we will grow new human tissues by injecting human stem cells into the same tissue engineering chambers in mice which will tolerate cells from other mammals (these are known as SCID mice). Success in novel method would be the precursor for the production of new human tissues to repair specific defects.Read moreRead less
Optimising Islet Transplantation With Vascularized Tissue Engineering Chambers
Funder
National Health and Medical Research Council
Funding Amount
$451,651.00
Summary
Diabetics have high blood sugar levels because cells in the pancreas known as islets produce too little of the hormone insulin. Most diabetics need daily insulin injections to maintain normal blood sugar levels. Transplanting islets is the most promising way to treat type 1 diabetes, but, apart from the obvious difficulty of rejection of foreign islets, several major problems remain: (1) there are insufficient pancreata (and therefore islets) for transplantation; and (2) the efficiency of delive ....Diabetics have high blood sugar levels because cells in the pancreas known as islets produce too little of the hormone insulin. Most diabetics need daily insulin injections to maintain normal blood sugar levels. Transplanting islets is the most promising way to treat type 1 diabetes, but, apart from the obvious difficulty of rejection of foreign islets, several major problems remain: (1) there are insufficient pancreata (and therefore islets) for transplantation; and (2) the efficiency of delivery of surviving islet transplants is too low. In pilot studies we have grown a new living pancreatic organ in mice by inserting islets from genetically-related mice together with a structural protein matrix, growth factors and blood vessels inside a plastic chamber. The blood vessels maintain nutrition to the islet cells and simultaneously allow insulin to be released into the bloodstream, thus normalising the high blood sugar in diabetics. In Aim 1 of these experiments we will find the optimal way to grow mature islets in blood vessel-containing chambers in diabetic mice, focusing on (a) the best time to add islets to the chamber - 0, 1 or 2 weeks after establishment, (b) the minimum number of islets to effectively normalise blood sugar and (c) how long we can keep islets alive and functional in chambers, examining periods up to 12 months. In Aim 2 we will test the ability of islet stem cells (provided by our co-investigators at Walter and Eliza Hall Institute, Melbourne) to survive in the chambers and to produce sufficient insulin to effectively lower blood sugar levels to normal in diabetic mice. In Aim 3 we will grow human islets in chambers in special diabetic mice that do not reject foreign tissue, in order to confirm similar behaviour of human islets in this controlled environment. Using this data, we hope to create a research model of functioning islets, that is accessible, retrievable and manipulable, for the further study of diabetes and transplantation.Read moreRead less