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This is potentially an interesting exercise, but without a lot more context it’s hard to say what additional controls are necessary. It’s conceivable that this data demonstrates sufficient antibody specificity for a narrow set of downstream experiments – maybe everything is done by overexpressing Protein X-HA, using the HA tag to immunoprecipitate, and using this new antibody for blots.
Of course, more controls are usually a good idea. If downstream experiments are used to analyze endogenously expressed protein in some cell or tissue of interest, it becomes critical to demonstrate specificity by knockdown/knockout. Ideally in the exact sample being analyzed, but that can be infeasible or impossible.
(I’ve always used null mutants to validate the antibodies I’ve made, but that’s with the luxury of model organism genetics and stock centers. We can’t expect every mouse researcher to make a knockout just to validate their antibody, and there’s no way to do the knockdown/knockout in human primary tissue samples)
Full blots should also be provided as a matter of course, but that’s something I’d probably leave to the journal editor to enforce their submission guidelines. But again, context matters. If later experiments rely on the antibody to detect cleavage products, dimers, or anything else of a different molecular weight, showing this blot uncropped is absolutely critical.