Some targets have dozens of published clones and few that work. What they have in common is that the signal is low, moves, or sits in a family of near identical proteins, so the control rather than the clone is what makes the result mean something.
An ehmt1 antibody and a chromatin target
An ehmt1 antibody reports a histone methyltransferase that works in a complex with its close relative, so a clone has to be shown not to see the partner, and the nuclear signal is diffuse rather than punctate. A knockdown lysate and a complex member stained in parallel are the controls that make a nuclear stain interpretable.
A rab5a antibody and detecting a trafficking protein
A rab5a antibody reports an early endosome protein that is small, membrane associated and one of a large family, so the signal is punctate and the specificity question is which family member is being seen. Co-staining with a second early endosome marker is the practical check, since the pattern rather than the intensity is the result.
A dc marker panel, and why one marker is never enough
A dc marker is never used alone, because no single antigen defines a dendritic cell: the subsets are resolved by a combination and by excluding the lineages that share individual markers. A panel designed on the subset wanted, with the exclusion channel included, is what makes a rare population readable at all.
immunohistochemistry vs immunofluorescence, and which the target needs
In immunohistochemistry vs immunofluorescence the choice is chromogen against fluorophore: chromogen gives a permanent slide readable on any microscope and a limited dynamic range, while fluorescence gives several targets at once, better co-localisation and a signal that fades. A low abundance or co-localised target needs fluorescence; a routine scored stain does not.
A fully humanized monoclonal antibody and its detection
A fully humanized monoclonal antibody carries human frameworks, which makes it invisible to the anti species secondaries used to detect a mouse clone and is why detecting one in a human sample needs an anti idiotype or a labelled format. The same property is what lowers its immunogenicity as a therapeutic.
Questions people ask about fancd2 antibody
What proves a clone against a family member?
A knockdown lysate plus the relative stained in parallel. A peptide competition proves less.
Chromogen or fluorescence?
Fluorescence for low abundance and co-localisation; chromogen for a routine scored stain on any microscope.
Why is one dendritic cell marker not enough?
No single antigen defines the cell. The subsets need a combination with a lineage exclusion channel.