ABSTRACT
Thalidomide has been shown to selectively inhibit TNF-alpha production in vitro by lipopolysaccharide (LPS)-stimulated monocytes. TNF-alpha has been shown to play a pivotal role in the pathophysiology of endototoxic shock. Using a mouse model of LPS-induced shock, we investigated the effects of thalidomide on the introduction of TNF-alpha and other cytokines and on animal survival. After injecton of 100-350 mug LPS into mice, cytokines including TNF-alpha, IL-6, IL-10, IL-1beta, GM-CSF and IFN-gamma were measured in the serum. Administration of 200 mg/kg thalidomide to mice before LPS challenge modified the profile of LPS-induced cytokine secretion. Serum TNF-alpha levels were reduced by 93 percent, in a dose-dependent manner, and TNF-alpha mRNA expression in the spleens of mice was reduced by 70 percent. Serum IL-6 levels were also inhibited by 50 percent. Thalidomide induced a two-fold increase in serum IL-10 levels. Thalidomide treatment did not interfere with the production of GM-CSF, IL-1beta or IFN-gamma. The LD50 of LPS in this model was increased by thalidomide pre-treatment from 150 mug to 300 mug in 72 h. Thus, at otherwise lethal doses of LPS, thalidomide treatment was found to protect animals from death.
Subject(s)
Mice , Animals , Female , Disease Models, Animal , Lipopolysaccharides , Shock, Septic/drug therapy , Thalidomide/pharmacologyABSTRACT
Studies were caried out to determine the effect of intra-dermal injections of recombinant human interferon-gamma (rIFNy) on the viability of Mycobacterium leprae. Twenty-three untreated and 4 treated multibacillary patients, 12 with lepromatous leprosy (LL) and 15 with bordeline lepromatous leprosy (BL), were selected for intradermal administration of rIFNy or PPD. Treated patients (LL and BL) had received multi-drug therapy according to the recommendations of the World Health Organization, i. e., rifampicxin (600 mg/month), dapsone (100 mg/day) and clofazimine (50 mg/day and 300 mg/month) for 1-4 months. Three daily doses of 10 or 30 ug rIFNy induced local induration and mononuclear leucocyte accumulation. Bacteria isolated from a punch biopsy of the site 21 days after lymphokine administration were injected into mouse foot pads and evaluated for viability and growth. The local response to rIFN (specific activity 2 x 10 7 units/mg protein) induced a delay or total inhibition of M. leprae growth in the mouse foot pad, ,indicating that the cellular response to the antigen reduced local M. leprae viability. The extent of reduction in viability depended on the dose of rIFNy injected and the extent of local induration induced by the lymphokine. With a vigorous cell-mediated immune response growth was fully inhibited. A similar but less extensive effect on M. leprae viability was observed in resapo0nse to the local injection of 5 units in 0.1 ml of purified protein derivative of tuberculin (PPD)