Study highlights how processing choices shape canine marrow IHC

CURRENT BRIEF VERSION: A new Veterinary Pathology study examined how fixation and demineralization methods affect immunohistochemical assessment of canine bone marrow, a practical issue for labs working up marrow biopsies in dogs with suspected hematologic disease. In the study, sternal bone marrow collected within 24 hours of death was fixed in either acetic acid-zinc-formalin or 10% neutral-buffered formalin, then decalcified with hydrochloric acid, formic acid, or EDTA before immunohistochemistry was performed. While the supplied abstract points to the IHC question directly, related work from the same research group found that EDTA-based decalcification preserved bone marrow morphology and downstream molecular performance better than acid-based methods, with hydrochloric acid performing worst and formic acid falling in between. That broader pattern is consistent with published human pathology literature, newer bone marrow IHC pilot data, and even other calcified-tissue molecular workflows, including a deer antler and trophy skull study that used EDTA-based digestion to recover DNA suitable for complete microsatellite genotyping from all samples. Together, those data reinforce the idea that gentler, chelation-based processing better protects analytes when antigen or nucleic acid preservation matters. (pmc.ncbi.nlm.nih.gov)

Why it matters: For veterinary professionals, this is less about a niche lab workflow detail and more about diagnostic confidence. Bone marrow biopsies are often pursued when clinicians need answers on leukemia, lymphoma, myelodysplasia, severe cytopenias, or unexplained inflammatory disease, and IHC can be central to lineage assignment and case classification. If decalcification weakens or distorts antigen staining, a case can become harder to interpret or require repeat testing. The emerging message across veterinary and comparative pathology is that gentler, standardized processing, especially neutral-buffered formalin fixation and EDTA decalcification, may improve the reliability of both IHC and molecular assays, even if it slows turnaround time somewhat. That same principle is showing up in other hard-tissue settings where EDTA-supported workflows have enabled successful downstream DNA testing from heavily processed specimens. (acvp.org)

What to watch: Watch for whether veterinary diagnostic labs update marrow biopsy protocols toward EDTA-based decalcification and whether follow-up studies define which specific canine marrow IHC markers are most sensitive to processing choices. It will also be worth watching whether veterinary labs increasingly align marrow handling with broader hard-tissue molecular best practices that prioritize analyte preservation over speed. (pubmed.ncbi.nlm.nih.gov)