HARIS SADDIQUE

M.PHIL SCHOLAR

DEPTT: OF BIOTECHNOLOGY

UNIVERSITY OF MALAKAND

KPK,PAKISTAN

STEM CELL ON HISTORY PAGES

1950/51Leon jacobson and

Egon lorenz show that mice can servive irradiation of their spleen are shielded or if bone marrow infusion are given. these results inspire additional studies, which suggest that spleen or bone marrow cells may reconstitute ravaged hematopoietic system

1957First human bone

marrow transplants are performed by E. Donnall Thomas and colleagues, in an attempt to cure patient dying of leukemia. This treatment called “intravenous infusion” is unsuccessful

1959E. Donnall Thom and

colleagues carryout bone marrow transplants between sets of identical twins. Two leukemia patients shows prompt hemoatologic recovery and well-being demonstrated that intravenous infusion of arrow can protect against lethal irradiation

1960/61Ernest McCulloch and

James Till show that stem cells self-renew and differentiate. Their technique, the colony forming unit spleen assay, is an early attempt to quantitate in vivo the immature cells in mouse bone-marrow that can reconstitute the hematopoietic system.

1962Using nuclear

transplantation, John B. Gordon shows that cell specialization is reversible. He transfers the nucleus from a frogs mature intestinal cell into an enucleated egg, and the modified egg develops into a normal tadpole.

1965/66An in vitro assay is

developed for the identification and quantitation of hematopoietic protogenitor cells—the immature cells that arise directly from hematopoietic stem cells. Two teams-Bradley and Metcalf, and Pluznik and Sachs—develop the assay independently.

1968/69Mixed leukocyte

culture, a test-tube-based assessment of Immune compatibility, enables the first two successful allogeneic bone marrow transplants. In each transplant (one by Fritz Bach's team, the other by Robert Good's team), a boy receives tissue from his sister.

1977A system is developed

to study hematopoiesis in vitro. This system becomes possible after TM. Dexter and colleagues realize that stromal cell support can be used to control the proliferation of hematopoietic stem cells in long-term culture.

1979/81Another transplant

modality, peripheral blood stem cell transplantation, enters clinical use. Attempts by UCLA (1979) and the NIH (1980) fail, possibly because transfusions contain too few protogenitor cells. But 'Johns Hopkins (1981) provides first evidence of hemotopoietic reconstitution.

1980/81Mouse embryonic

stem cells are established in culture. Martin Evans and Matthew Kaufman and, working independently, Gail Martin develop cell lines from the inner cell mass of blastocyst-stage embryos.

1984

Hematopoietic stem cells from mice are isolated from other bone marrow cells. To accomplish the task, J. Visser and colleagues utilize flow cytometry.

1988

Using refined cell-separation techniques, G. Spangrude. S. Heimfeld, and I. Weissman purify and characterize hematopoietic stem cells from mice.

1988

Four embryonic stem cell lines are created from Mesocricetus auratus, the Syrian golden hamster. These lines, the first in vitro lines not derived from mice, anticipate an even greater diversification of stem cell sources.

1988Umbilical cord blood

transplantation is used to treat a child with Fanconi anemia. This pioneering effort, led by Eliane Gluckman and Hal E. Broxmeyer, was eventually followed by thousands of cord blood transplants addressing a wide range of disorders.

1990The Nobel Prize in

Physiology or Medicine is awarded jointly to Joseph E. Murray and E. Donnall Thomas ‘for their discoveries concerning organ and cell transplantation in the treatment of human disease.’

1995Embryonic stem cells

are derived from non human primates for the first time by J.A. Thomson and colleagues. This result, from rhesus monkeys and marmosets, raises expectations that such cells could be derived from humans.

1996Dolly, a female

sheep soon to be famous as the first cloned mammal, is born. Her creation, orchestrated by Ian Wilmut and colleagues, involves the transplant of a nucleus, taken from an adult sheep, into an enucleated egg.

1998The isolation of human

embryonic stem cells is reported by J.A. Thomson and colleagues. Despite their enormous potential for research and treatment, human stem cell raise controversy because their derivation requires the destruction of human embryos.

2000The NIH publishes

guidelines for research using human pluripotent stem cells. The guidelines are intended to help ensure that ‘NIH-funded research in this area is conducted in an ethical and legal manner."

2001

The United Kingdom becomes the first country to pass a law governing the use of human embryos for stem cell research.

2006Induced pluripotent

stem cells (iPSCs) are produced from mouse cells by S. Yamanaka and K. Takahashi. The derivation is accomplished via the transfection of certain stem cell-associated genes into adult somatic cells.

2007iPSCs are produced

from human cells by S. Yamanaka’s team and Independently by J.A. Thomson's team. Because human iPSCs are obtained without destroying human embryos. They occasion less controversy. The vigors of induction, however, produce less capable stem cells.

2007The Nobel Prize in

Physiology or Medicine is awarded to Mario R. Copecchi, Sir Martin J. Evans, and Oliver Smithies ‘for their discoveries of principles for introducing specific gene modifications in mice by the use of embryonic stem cells.’

2010Geron launches a

clinical trial of a therapy that uses human embryonic stem cells. The trial, for patients with severe spinal cord injuries, is halted a year later after Geron cites financial problems.

2010Advanced CeIl

Technology (ACT) gets FDA approval to test a stem cell therapy for Stargardt’s macular dystrophy. After Geron halts its trial, ACT’ is the sole company conducting a clinical trial involving human embryonic stem cells.

2011A federal judge

dismisses a lawsuit challenging the NIH’s policy for funding human embryonic stem cell research. The plaintiffs, adult stem cell researchers had argued that the NIH’s policy promoted embryo destruction.

2012The Nobel Prize in

Physiology or Medicine is awarded jointly to Sir John B. Gordon and Shinya Yamanaka ‘for the discovery that mature cells can be reprogrammed to become pluripotent.’

2013Human pluripotent

stem cells are produced via the nuclear transfer technique. One key change, adding caffeine to the eggs before DNA transfer, allows S. Mitalipov and colleagues to extend cloning to humans.

2013Raising hopes that

shortages of donor organs could be eliminated, a team of scientists led by T. Takebe uses iPSCs to grow tissue resembling human liver in a mouse.

2013In an advance that

anticipates future commercial applications, scientists unveil a test-tube burger. Made from bovine skeleton stem cells, the meat is costly, yet proponents say that mass production remains a possibility.

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