In the prior paper an interesting apparently patentably novel functional screening utilizing arrays of cells was disclosed.

Lysogenic Bacteria, Capable of Therapeutic Virus Liberation Subsequent to Tumor Cell Targeting

Figure 1 is a recap of the previously described process.

Figures 2 and 3 exemplify derivations of this functional assay.

In Figure 2, we start with a section of a microtiter plate, into whose wells identical targets have been placed. Such targets can be cells or functional molecules (e.g. enzymes), and may be support-affixed or free in solution. The first step is to 'array' different library member cells, singly or in relatively small groups. An efficient method of doing this would be to spray a dilute solution of the library over the entire surface of the plate. Next these cells are clonally expanded so as to provide sufficient target binders such that affected targets can be identified.

Target binders (whose expression is perhaps induced) would commonly be peptides or proteins, protein-associated nucleic acids (including viruses such as phage), or naked nucleic acids. Such target binders may be secreted, expressed on the cell surface, or liberated upon cell lysis.

Figure 3 is a derivation wherein the library members are first arrayed, expanded, and then contacted with target cells or molecules.

In this depiction the library members are nonrandomly arrayed, perhaps by being sprayed onto precisely positioned agar gel pads. Random arrays are of course a an alternative.

An example of a molecular target applied to an array as in Figure 3 would be a viral protease such as that of HIV. Subsequent to their spray application to the expanded library array of cells, perhaps secreting recombinant phage, a labeled peptide substrate could be applied, again perhaps via spraying. Those loci wherein this peptide was not cleaved, perhaps identified microscopically, would identify the library member cell(s) whose product(s) inhibited the protease.

Utilizing an array as in Figure 3 with a cellular target would allow for the identification of antimicrobials or anticancers. For example, let us fabricate and arrayed library yeast cells, each member of which secrets a different polypeptide. To such an array one could apply target bacteria, perhaps suspended in liquid agar, and subsequent to incubation determine which yeast library member(s) secreted a growth inhibitory polypeptide(s).

Another version of the process in Figure 3 is shown in Figure 4.

Herein library cells and target cells are cocultivated, the target cells being present in the layer of agar prior to application of library cells.

An even simpler alternative is to disperse both target cells and library cells prior to layering on the surface.

As an alternative to the solution and support-based arrays of Figures 2-4 wherein the loci comprise clonally expanding cell library members, an array could be fabricated via applying a library of different naked or complexed nucleic acids (including viruses and particle conjugates) to a clonal population of host cells. Subsequent to penetrating host cells, the library members are replicated, transcribed, and/or translated. The products thereof may be naturally liberated from the host cells or could be liberated by host cell lysis. These free expansion products then contact, or are contacted with targets with the anticipation that some thereof will affect the targets

Provisional claims directed to some important aspects of the invention.

It has now been appreciated that arrays of clonally expanded nucleic acids or their polypeptide products need not require cells. That is one could initially array the members of a library of nucleic acids or complexes thereof, perhaps by spraying. Subsequently 'clonally expand' these nucleic acid arrayed nucleic acid library members via in vitro replication, transcription, and/or translation.

As indicated above for cells, array loci may contain one library member, a relatively small group of members, or no members at all.

Such a process would allow for easy incorporation of unnatural monomers, such as unnatural amino acids.

Provisional claim