What Is Cytoplasmic Staining?

Cytoplasmic staining occurs when the liquid contained within a cell is discolored. This occurs for one of two reasons: either because the cell has become deficient in some way or because it has been stained for the purposes of scientific analysis. Viruses such as the cytomegalovirus and cancers such as hepatocellular carcinoma can cause granulated staining of the cytoplasm. Scientists stain cytoplasms in order to create a color contrast when studying specific elements of a cell.

The cytoplasm is a viscous liquid contained within a cell’s membrane. It is a feature of both prokaryotic and eukaryotic cells. The cytoplasm in a prokaryotic cell contains all of the cell's genetic material, proteins and other materials. In a eukaryotic cell, many of the cell's functions are performed within self-contained organelles. Nearly 70 percent of a eukaryotic cell’s cytoplasm is made up of cytosol, the actual liquid, which contains mostly water, salt and soluble molecules such as proteins, lipids and carbohydrates.

Cytomegalovirus (CMV) is a type of herpesvirus that can infect humans as well as other organisms and is one example of a condition that can cause cytoplasmic staining. The human variant, HCMV, only causes massive damage to patients with suppressed immune systems such as those with Human Immunodeficiency Virus (HIV). Cytoplasmic staining occurs in a minute number of cells affected by CMV. Studies have proved that cytoplasmic staining of cells infected by CMV is random and not diagnostic.

Scientific cytoplasmic staining happens when a class-specific dye is added to the cytoplasm. Rather than staining the whole of the cytoplasm or cytosol, the dye targets specific elements of it such as organelles, proteins or deoxyribonucleic acid (DNA). The dye is applied either when the cell is alive (in vivo) or when the cell is dead (in vitro). The samples, after dyeing, are studied using microscopes.

The process of staining varies depending on what is being targeted and why. Research laboratories tend to have protocols in place for staining each type of cell. For example, research into the staining of cells during hepatocellular carcinoma requires immunochemical staining as its preferred method of cytoplasmic staining in order to study the body’s response to the carcinoma. This process includes deparaffinization, a hydrogen peroxide wash and heating of the sample in an antigen retrieval solution.

Hepatocellular carcinoma is a relatively common form of malignant cancer in humans. It is a cancer that primarily affects the liver and there are roughly 16,000 new cases of the cancer each year in the United States. A dye or maker, called Thyroid Transcription Factor-1 (TTF), has been developed by scientists to distinguish primary cancer cells from the more dangerous metastatic cancer cells.