title: Chloroquine stimulates the mitogen-driven lymphocyte proliferation in patients with psoriasis.
abstract: Chloroquine is known to exacerbate psoriasis. Since immunological stimuli are considered to be important for the pathogenesis of psoriasis, we compared the effects of chloroquine on cell-mediated immunity in 15 healthy control individuals and 15 patients with psoriasis. We employed the spontaneous and phytohemagglutin (PHA)-induced uptake of 3H-thymidine to measure lymphocyte proliferation. Chloroquine was added to the cultures at concentrations ranging from 0.022 to 220 microM. We found that both spontaneous and PHA-driven lymphocyte proliferations were significantly lower in patients with psoriasis (p < 0.002). The spontaneous blastogenesis in both controls and patients remained stable under chloroquine. In PHA-driven cultures in controls, 0.022-2.2 microM chloroquine had no effect, higher concentrations of the drug suppressed proliferation. In patients, 22 microM chloroquine surmounted the suppression of the PHA-induced proliferative response found in controls; moreover, 2.2-0.022 microM chloroquine increased lymphocyte proliferation by > 300% (p < 0.002). Our data indicate that in psoriasis the lower lymphocyte transformation is abnormally stimulated by the addition of pharmacological doses of chloroquine.
authors.affiliation: Department of Dermatology, Johannes Gutenberg University, Mainz, FRG.
authors.forename: R E
authors.initials: RE
authors.lastname: Schopf
authors.forename: H M
authors.initials: HM
authors.lastname: Ockenfels
authors.forename: T
authors.initials: T
authors.lastname: Schultewolter
authors.forename: B
authors.initials: B
authors.lastname: Morsches
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D002738:Chloroquine / Q000009:adverse effects* / Q000494:pharmacology* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D010835:Phytohemagglutinins / Q000494:pharmacology*; D011565:Psoriasis / Q000188:drug therapy / Q000276:immunology / Q000473:pathology*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000473:pathology*
chemical_list: D010835:Phytohemagglutinins; D002738:Chloroquine