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Lymphocyte Isolation from Human Skin for Phenotypic Analysis and Ex Vivo Cell Culture
Published on: April 8, 2016
PUVA apoptotic response in activated and resting human lymphocytes
A E Heng1, B Sauvezie, L Genestier
1Service de Néphrologie (Pr Deteix) Henri Dunant BP69 63003, CHU, Clermont-Ferrand Cedex, France. aheng@chu-clermontferrand.fr
Summary
Extracorporeal photopheresis (ECP) with PUVA treatment induces apoptosis equally in resting and activated lymphocytes. Monocytes may influence lymphocyte apoptosis during preincubation, suggesting complex mechanisms in ECP therapy.
Area of Science:
- Immunology
- Photobiology
- Cellular Biology
Background:
- Extracorporeal photopheresis (ECP) utilizes 8-methoxypsoralen and UVA (PUVA) to induce apoptosis in collected cells.
- The precise mechanism by which reinfused cells exert therapeutic effects in ECP remains unclear.
- A vaccination model suggests ECP efficacy relies on the immune system's presentation of apoptotic alloreactive cells.
Purpose of the Study:
- To investigate the susceptibility of resting and PHA-activated lymphocytes to PUVA-induced apoptosis.
- To explore the potential influence of preincubation, including monocyte-lymphocyte interactions, on apoptosis induction.
- To assess whether PUVA exhibits selectivity towards activated lymphocytes.
Main Methods:
- Lymphocytes, both resting and PHA-activated, were subjected to PUVA treatment.
- Preincubation of lymphocytes, with and without monocytes, was performed before PUVA exposure.
- Apoptosis levels were evaluated at various time points, and membrane marker expression was analyzed.
Main Results:
- Both resting and PHA-activated lymphocytes demonstrated equal susceptibility to PUVA-induced apoptosis.
- Preincubation for 72 hours, particularly with monocytes, led to an increased number of apoptotic cells in both resting and stimulated lymphocytes.
- Activation status modified the expression of certain membrane markers targeted by PUVA.
Conclusions:
- The study found no difference in PUVA-induced apoptosis susceptibility between resting and activated lymphocytes.
- Monocytes may play a role in modulating lymphocyte apoptosis during the preincubation phase of ECP.
- While direct apoptosis selectivity was not observed, PUVA's interaction with lymphocyte membrane markers is influenced by activation status, suggesting potential indirect selectivity mechanisms.
