Immunohistochemistry
General Information
IHC Submissions
Immunohistochemistry General Information
Immunohistochemistry (IHC) uses immunologic and histologic techniques to detect antigens in tissues. The antigen is recognized by a specific antibody that is added to the tissue section. The immunologic reaction is visualized under the microscope by adding an enzyme, a substrate to the enzyme, and a chromogen, producing a colored reaction. IHC is a very sensitive and specific technique. For diagnosticians, it is an important technique that allows us to colocalize antigens and lesions in the same tissue section.
Neoplastic and infectious diseases are the main focus of IHC in veterinary medicine. The ADDL IHC Service offers a variety of tests for both infectious and neoplastic diseases:
  • Diagnosis of neoplasia: Often, the tissue of origin of a tumor cannot be determined with routine histology. Using specific antibodies for different tissues or cells (e.g. cytokeratin for epithelium, vimentin for mesenchymal cells, lymphoid markers, etc), the origin of many tumors can be determined with IHC.
  • Diagnosis of micrometastases: Early metastasis can be difficult to detect using conventional histology. IHC highlights the presence of single or small groups of neoplastic cells in metastatic sites. Early detection of micrometastases increases the chances of survival with surgical removal of affected nodes or by modification of the treatment protocol.
  • Prognostic markers: Some proteins are expressed in neoplastic, but not in normal, mature cells (e.g., embryonal proteins), expressed in neoplastic cells in larger amounts than in normal cells (e.g. cycle-related proteins), or structurally modified in neoplastic cells (mutant p53 protein). These changes may have prognostic significance in specific tumor types. For instance, it has been reported that the immunohistochemical detection of c-Kit protein in mast cell tumors of dogs has prognostic significance. Some of these markers are being tested to determine their significance in veterinary cancers.
  • Diagnosis of infectious diseases: Detection of antigens of an infectious agent using IHC has etiologic significance. Antigen detection can be correlated with histopathologic changes and thus can confirm the significance of a particular microorganism detected by other methods.
How to Submit Samples for Immunohistochemical Testing
  • Please complete a CF.369 Regular Submission Form or CF.392 Neoplasm Submission Form and submit with sample. Forms are available on the Forms page.
  • We test samples that have been fixed in formalin, so you do not have to do anything special.
  • Submit the sample as you would for routine histopathology.
  • Do not hold fixed samples in your office longer than 2 days as prolonged fixation may destroy antigens. As soon as you place your sample in formalin, send it to the ADDL.
Infectious Diseases
Adenovirus
Aspergillus
Bovine respiratory syncytial virus
Bovine virus diarrhea
Calicivirus
Coronavirus, bovine
Coronavirus, porcine
Coronavirus, feline
Distemper virus
Feline leukemia virus
Francisella tularensis
Herpesvirus 1, bovine
Herpesvirus 1, equine
Influenza A
Lawsonia
Leptospira
Listeria
Mycobacterium bovis
Papilloma virus
Parvovirus, canine
Porcine circovirus 2
PRRS virus
Rotavirus A
West Nile Virus
Yersinia pestis
Tissue/Cell MarkerUse
Actin, muscleAll muscle
Actin, sarcomericStriated muscle
Actin, smooth muscleSmooth muscle
B-cell marker (BLA36)B-cell lymphoma, some histiocytic tumors
CD3T-cell lymphoma
CD10Renal tubular epithelium
CD11dSome histiocytic tumors
CD18Leukocytic tumors
CD20B-cell lymphoma
CD31Vascular tumors
CD45Leukocytic tumors
CD68Histiocytes
CD79aB-cell lymphoma
CD117 (c-Kit protein)Mast cell tumors
CalcitoninC-cell tumors of thyroid gland
CalretininRenal tubules, nerve tissue
E-CadherinLangerhan cells, epithelium, histiocytomas
Caspase-3Apoptotic cells
Chromogranin AGeneral neuroendocrine marker
COX-2Carcinomas
COX-1Normal urothelium, endothelium
Cytokeratin 5Myoepithelium, basal cells
Cytokeratin 7Glandular epithelium
Cytokeratins (MNF and AE1/AE3)General epithelial marker
Cytokeratins high molecular weightSquamous epithelium, mesothelium, hepatocytes
DesminMuscle tumors
Estrogen receptorEstrogen receptor-positive tissues and tumors
Factor VIII-related antigenVascular tumors
Glial fibrillary acidic proteinNeural (glial) tumors
GlucagonPancreatic islet tumors
Glucose transporter (Glut-1)Peripheral nerves, kidney
Hepatocyte marker 1Hepatocytes and their tumors
Tissue/Cell MarkerUse
Immunoglobulin kappa chainsPlasmacytomas, immunocomplex disease
Immunoglobulin lambda chainsPlasmacytomas, immunocomplex disease
Inhibin-alphaSex-cord testicular and adrenal cortical tumors
InsulinInsulin-producing tumors
Ki-67Cell proliferation
LysozymeHistiocytes
Melan AMelanomas, steroid-producing tumors
MHCAntigen presenting cells, lymphocytes
Microphthalmia transcription factorMelanomas
MUM1Plasmacytomas, some B-cell tumors
MyoglobinStriated muscle
Myeloid-histiocytic markerMacrophages, myeloid cells
Natural killerPeripheral nerve cell tumors
Nerve growth factor receptorNeural tumors
NeurofilamentNeural tumors
Neuron specific enolaseGeneral neuroendocrine marker
p63Myoepithelium, basal cells
PGP 9.5General neuroendocrine marker
Progesterone receptorPositive tissues/tumors
S-100 proteinGeneral neural marker, neuroendocrine tumors
SomastotatinPancreatic islet cell tumors
SynaptophysinGeneral neuroendocrine marker
ThyroglobulinThyroglobulin-producing cells
Thyroid transcription factor 1Lung/thyroid tumors
TryptaseMast cell tumors
Uroplakin IIIUrothelium and its tumors
VimentinGeneral marker for mesenchymal tumors