(Covers information from Anderson's universe)
As part of the Umbrella Science Division's research into treating those infected with the T-virus, Isaacs commissioned Clone 88 as another in a long line of potential sources of blood for research; the cloning procedure had been unsuccessful in fully-replicating Alice, thus leading to further attempts.
Clone 88 was awoken premature from her maturation chamber while Alice was fighting Dr. Isaacs, now transformed into a powerful monster. Struggling for air, she passed out in Alice's arms; mistaken for death, a jacket was covered over her body to preserve her decency.
She revived in time to deactivate the lasers in the nearby testing ground, doing so only after they sliced Issacs to pieces. This act saved Alice seconds before she would have died too. Clone 88 stood by Alice's side as she began awakening further clones to assemble an anti-Umbrella army.
This clone presumably was part of Alice's army in Afterlife and thus died with the rest of Alice's clones.