Interleukin-16 as a marker of Sézary syndrome onset and stage.
BACKGROUND
Sézary syndrome is one of the most common forms of cutaneous T cell lymphoma (CTCL). It is characterized by skin infiltration of malignant T cells. We examined interleukin-16, a potent T cell chemoattractant and cell-cycle regulator, as a prospective marker of disease onset and stage.


METHODS
The correlation of total intracellular interleukin-16 and surface CD26 was studied by flow cytometry. Confocal microscopy was performed to determine localization of interleukin-16 at different stages of the disease. The levels of interleukin-16 in plasma and culture supernatants were examined by enzyme-linked immunoassay. Additionally, lymphocytes from stage IB patients were cultured in the presence of interleukin-16 alone and in combination with interleukin-15, and their ability to survive and proliferate was determined by cell counts and [3H]TdR incorporation.


RESULTS
The data indicate that loss of both nuclear and intracellular pro-interleukin-16 highly correspond to disease stage, with a concomitant increase in secreted mature interleukin-16 in both culture supernatants and patients' plasma that peaks at stage IB. Loss of intracellular interleukin-16 strongly corresponded to loss of surface CD26, which has been shown to occur with more advanced stage of CTCL. Nuclear translocation of pro-interleukin-16 was not observed in late stages of Sézary syndrome, indicating this loss is not reversible.


CONCLUSIONS
We propose that it is feasible to use plasma levels of IL-16 as a potential diagnostic marker of Sézary syndrome and to use loss of intracellular IL-16 as a prognostic indicator of disease severity and stage.
Richmond
Jillian
J
Pulmonary Center, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA.
Tuzova
Marina
M
Parks
Ashley
A
Adams
Natalie
N
Martin
Elizabeth
E
Tawa
Marianne
M
Morrison
Lynne
L
Chaney
Keri
K
Kupper
Thomas S
TS
Curiel-Lewandrowski
Clara
C
Cruikshank
William
W
D000368:Aged; D018819:Dipeptidyl Peptidase 4 / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D019410:Interleukin-16 / Q000097:blood* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012720:Severity of Illness Index; D012751:Sezary Syndrome / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*; D012878:Skin Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000503:physiopathology*
D019410:Interleukin-16; C042807:DPP4 protein, human; D018819:Dipeptidyl Peptidase 4