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Preserved today. Possible later.Some goodbyes are optional.The dots are alive.Abu Dhabi · Bahrain · CaliforniaA writing system for life itself.
Preserved today. Possible later.Some goodbyes are optional.The dots are alive.Abu Dhabi · Bahrain · CaliforniaA writing system for life itself.
reem bio

Science

The method,shown in full.

Everything we offer rests on one ordinary laboratory skill: keeping cells alive. Here is how we do it, and the evidence behind it. Terms are defined in the glossary.

Brightfield micrograph of fibroblasts migrating out of a dark tissue explant, with a 200 micrometre scale bar.
client-culture.jpg
fig. 1 – Explant culture – fibroblasts leaving the tissue, shortly before cryopreservation. Felis catus, a client's line.
A rack of frosted cryoboxes lifted from a liquid nitrogen dewar, vapour drifting around it.
lab-cryoboxes.jpg
fig. 2 – Cryoboxes lifted from liquid nitrogen vapour.
A micromanipulator rig with fine pipettes positioned over a culture dish on an inverted microscope.
lab-micromanipulator.jpg
fig. 3 – Micromanipulation, where nuclear transfer begins.

i.

Culture

A biopsy is cut into fragments of about a millimetre and laid in a culture dish. Within days, fibroblasts migrate out of each fragment – the explant – and begin to divide. When they cover the dish they are lifted and spread into larger flasks. We stop at low passage, while the cells are young and their chromosomes stable.

ii.

The culture timeline

  1. Day 0

    Explant

    Tissue fragments plated.

  2. Day 3

    Outgrowth

    First fibroblasts appear.

  3. Day 14

    Confluence

    Cells cover the flask.

  4. Day 21

    Banked

    Tested, frozen, mirrored.

iii.

Cryopreservation

Cells are suspended in a protective medium, cooled at about one degree a minute, and moved to nitrogen vapour. Slow cooling lets water leave the cell before it can freeze into damaging crystals – a principle described in the 1970s and still the basis of cell banking today. One vial from every deposit is thawed and counted before the line is certified.¹

iv.

Nuclear transfer

Cloning uses micromanipulation: a fine glass pipette removes the nucleus of an egg, and a banked cell is fused with it. The method has produced healthy offspring in many mammals since 1997, including horses in 2003. Efficiency remains modest, which is why we state timelines as ranges on Continue.²

v.

The literature we build on

Our own papers will be listed here as they are published. Until then, these are the studies our methods rest on – each one open to anyone who wants to check our reasoning.

1984
Mazur – Freezing of living cells: mechanisms and implications. American Journal of Physiology.
1997
Wilmut et al. – Viable offspring derived from fetal and adult mammalian cells. Nature.
2002
Shin et al. – A cat cloned by nuclear transplantation. Nature.
2003
Galli et al. – A cloned horse born to its dam twin. Nature.
2010
Wani et al. – Production of the first cloned camel by somatic cell nuclear transfer. Biology of Reproduction.

vi.

Advisory board

Chair

Reproductive biology

Reviews
Nuclear transfer and surrogacy programmes
Meets
Quarterly
Seat

Veterinary medicine

Reviews
Animal welfare and collection protocols
Meets
Quarterly
Seat

Cryobiology

Reviews
Freezing, storage and thaw records
Meets
Twice a year

The board is independent of the laboratory: its members are not paid by results and can stop any programme on welfare grounds. Members are named here once their appointments are signed. The people at the bench are on the team page.

vii.

Standards

Sterility
Every line tested for bacteria and fungi before banking.
Mycoplasma
Every line screened by PCR before banking.
Identity
A DNA profile recorded for every line and checked at every later use.
Chain of custody
Barcoded vials, logged at every movement from biopsy to vault.
Welfare
Veterinary oversight of every animal involved, including surrogates.

Notes and sources

  1. ¹Mazur P. Freezing of living cells: mechanisms and implications. American Journal of Physiology 247, C125–C142 (1984).
  2. ²Wilmut I. et al. Viable offspring derived from fetal and adult mammalian cells. Nature 385, 810–813 (1997).
  3. ³Galli C. et al. A cloned horse born to its dam twin. Nature 424, 635 (2003).
  4. ⁴Shin T. et al. A cat cloned by nuclear transplantation. Nature 415, 859 (2002).
  5. ⁵Wani N.A. et al. Production of the first cloned camel by somatic cell nuclear transfer. Biology of Reproduction 82, 373–379 (2010).