Study highlights processing effects on canine marrow IHC

CURRENT BRIEF VERSION: A new Veterinary Pathology study adds practical evidence on a familiar lab problem: how fixation and demineralization choices affect immunohistochemical assessment of canine bone marrow. The researchers collected sternal bone marrow samples from dogs within 24 hours of death, fixed them in either acetic acid-zinc-formalin or 10% neutral-buffered formalin for 24 hours, then decalcified them with formic acid, hydrochloric acid, or EDTA for different time periods before IHC testing. In related conference reporting from the same group, EDTA produced the best overall IHC performance, while hydrochloric acid was associated with poorer antigen preservation; the work builds on the authors’ earlier 2024 paper showing that fixation and decalcification choices also affect bone marrow histomorphology and DNA amplification. That broader point also fits with other veterinary bone research: a recent Animals paper described a simple EDTA-based DNA extraction approach that generated complete microsatellite genotypes from all 60 tested deer antler and prepared trophy skull samples, underscoring how mineralized tissues can still support strong downstream molecular testing when processing is optimized. (acvp.org)

Why it matters: For veterinary pathologists and diagnostic labs, pre-analytic handling can shape whether a stain is interpretable or misleading. Bone and marrow samples routinely need decalcification, but both veterinary lab guidance and broader pathology literature note that this extra processing step can delay turnaround and compromise downstream IHC or molecular testing if harsher methods are used. The practical takeaway is that labs evaluating canine marrow biopsies may want to review whether their current decalcification workflow is optimized for antigen preservation, especially when lymphoma, leukemia, histiocytic disease, or other marrow-involving conditions depend on reliable immunophenotyping. The same principle matters for molecular work on mineralized specimens more broadly, including forensic and conservation testing. (cvm.msu.edu)

What to watch: Watch for the full peer-reviewed publication of the IHC-focused study and for whether veterinary diagnostic labs move toward EDTA-based marrow decalcification protocols despite the tradeoff of slower processing. (acvp.org)