Protein kinase C delta (PKCδ) and PKC theta (PKCθ) are serine/threonine kinases belonging to the novel PKC (nPKC) subfamily, characterized by calcium-independent activation and dependence on diacylglycerol (DAG) for signaling. PKCδ is ubiquitously expressed and plays diverse roles in apoptosis, cell growth, differentiation, and immune regulation. It is implicated in cancer, neurodegenerative disorders, and cardiovascular diseases. PKCθ, in contrast, exhibits selective expression in T cells, skeletal muscle, and platelets. It is a critical regulator of T-cell receptor (TCR) signaling, immune synapse formation, and cytokine production, making it a key player in autoimmune diseases and inflammatory responses.
Antibodies targeting PKCδ and PKCθ are widely used in research to study their expression, localization, phosphorylation status, and functional roles. For PKCδ, antibodies help investigate its dual pro- or anti-apoptotic roles in cancer or its involvement in oxidative stress pathways. PKCθ antibodies are essential for probing T-cell activation mechanisms, Th1/Th2 differentiation, and interactions with adaptor proteins like Vav1 or LAT. Both antibodies are validated in techniques such as Western blotting, immunofluorescence, flow cytometry, and immunohistochemistry.
Specificity is a key consideration, as PKC isoforms share structural homology. Phospho-specific antibodies detecting activated PKCδ (e.g., phosphorylated at Thr505) or PKCθ (phosphorylated at Thr538) are critical for assessing kinase activation. These tools have advanced studies in immunology, oncology, and drug development, particularly in exploring PKCθ inhibitors for autoimmune therapies or PKCδ modulators in cancer treatment.