Harold Katcher - Heterochronic Plasma Exchange

Harold Katcher is a professor of Biology at the University of Maryland.

Programmed aging theories contend that aging is a biological function that has evolved because it serves a purpose. In mammals and many other organisms, most biological functions such as reproduction, digestion, growth, fight/ flight response, and circadian, monthly, and annual cycles, involve signaling. Chemical signals distributed in the blood (e.g. hormones) coordinate activities of different tissues in order to accomplish the function. Katcher believes(1) signals in the blood of old mammals could direct tissues receiving the signals to age or allow aging to occur. Alternately or in addition, signals in the blood of young mammals could direct receiving tissues to activate anti-aging processes.

Plasmapheresis is a procedure that has been used since the 1960s to treat various diseases. In this procedure, blood is gradually removed from a patient and processed to separate the cells from the plasma. The cells are then returned to the patient in such a way as to maintain a safe blood supply. Donor plasma or manufactured plasma substitute can accompany the return of cells to the patient in order to replace removed plasma. Donor plasma can be obtained through plasmapheresis in which only cells are returned to the donor if quantities are restricted to one liter twice weekly. Plasmapheresis is used to treat diseases in which harmful components such as certain antibodies have accumulated in the plasma. Plasmapheresis is a mature accepted process and equipment for performing the processing is available.

Katcher thinks plasmapheresis could also be used to perform a heterochronic plasma exchange between young and old humans or other mammals. In this case, plasma taken from a young individual would be used to replace plasma removed from an old individual and thus cause reversal of the signal situation and consequent change in the direction received by tissues regarding aging. Such a procedure could be important in the treatment and prevention of age-related diseases and could also eventually lead to identifying the specific blood components responsible for enabling or inhibiting the aging process with obvious potential medical applications. Substantial experimental evidence supporting this approach already exists(1, 2).

Turritopsis Corp. is a company founded to pursue HPE research.

(1) Katcher H. Towards an Evidence-based Model of Aging. Current Aging Science: 46-55 2015

(2) Katcher H. Studies that shed new light on aging. March 2013

(3) Katcher H. Is prevention of ageing within our grasp? March 2011