Cell Biology and Human Health
All diseases are disturbances at the cellular level (Rudolph Virchow, 1858) To treat disease, we must understand its cause. To understand the cause of a disease, we must understand the alterations that occur at the level of individual cells.
With the elucidation of the human genome, we have greatly enhanced our potential for pinpointing the molecular aberrations responsible for even genetically complex diseases. However, identifying mutant genes or altered patterns of gene expression by themselves are insufficient to turn this information in to understanding or new therapies. The functions and cellular contexts of these gene products must also be understood, assays developed to enable their study, and models put in place to test new therapies. Thus, genomics and informatics will increasingly rely on cell biology and cell biologists.
Further, not all diseases are genetically based (infectious disease, for example) nor do all affect processes that can be easily revealed by gene expression patterns.
As the study of cell biology will become increasingly important to the study of disease, the study of the cellular basis of human disease has already produced some fundamental insights into cell biological principles.
Some major diseases elucidated, as a result of systematic cell biological analysis, include:
- Familial hypercholesterolemia (defective cellular uptake of lipoproteins; led to the development of "statins", widely taken to reduce cholesterol levels)
- Cystic fibrosis (chloride transport proteins are misfolded and retained in the endoplasmic reticulum, failing to reach their site of action at the cell surface)
- Lysosomal storage diseases (defective transport of hydrolytic enzymes)
- Alzheimers disease (defective processing of amyloid plaque precursor protein)
- Hypertension (defective endocytosis of sodium channels)
- Hypertension (defective formation of junctional complexes in kidney epithelial cells)
- Muscular dystrophy (defecive plasma membrane-associated cytoskeleton)
- Bullous pemphigoid (failed adherence among skin cells due to cytoskeleton defects)
- Pigmentation defects (defective maturation and transport of melanin granules in melanosomes in the skin)
- Several forms of cancer (defective transport of growth factor receptors, aberrant cell migration, defects in mechanisms of epithelial cell polarity, defects in cell cycle regulation)
- Virus infections (endocytosis, membrane fusion)
- Deafness due to mutations of myosin genes that control mechanotransduction in cells of the inner ear