J. Med. Chem. 1987, 30, 705-710
705
Inhibition of Delayed Hypersensitivity Reactions by Cinnamyl 1-Thioglycosides Mitree M. Ponpipom,* Robert L. Bugianesi, and Thomas J. Blake Merck Sharp & Dohme Research Laboratories, Rahway, New Jersey 07065. Received July 15, 1986 Cinnamyl 1-thio-a-D-manno(andL-rhamn0)pyranosideshave good inhibitory effects in an antigen-specific T cell proliferation assay. The fl anomers are slightly less effective than the a anomers. The 6-substituted analogues of cinnamyl 1-thio-oc-D-mannopyranoside such as 6-deoxy and 6-0-methylderivatives also block macrophages in presenting the antigen to T cells. D-Mannose and L-rhamnose,when tested by themselves with no modifications, did not block at concentrationsup to 1 mM. These cinnamyl 1-thioglycosideswhen given ip or PO at 3-30 mg/kg to mice significantly inhibited the delayed type hypersensitivity reaction as measured by footpad swelling. Macrophages can both degrade and present antigens. Some antigens characteristically stimulate an immune response that is mainly cellular. Such antigens are taken up by macrophages that deliver an immunogenic signal to the lymphocytes and, in particular, to T cells. The antigens, after being “presented” to T cells by macrophages, bind to receptors on the T cells, causing the cells to secrete lymphokines. Macrophage function is not restricted by the immune state of the animal from which the macrophage was obtained. However, macrophages and lymphocytes must share genetic identity a t some portion of the major histocompatibility complex for successful detection of the antigenic signal borne by the macr0phage.l Macrophage-lymphocyte interaction is a general requirement for T cell activation to cell surface antigens (alloantigens) as well as soluble protein antigens. Many of the biologic characteristics of antigen-specific T cell proliferation have been reviewed.2 It was suggested that autologous macrophage-T cell interactions are at least in part mediated by sugar-specific cellular receptor^.^^^ With tetanus toxoid as an antigen and human peripheral blood mononuclear cells as a responder population, a variety of simple sugars were found to markedly inhibit antigenspecific proliferative responses. For example, D-mannose, L-rhamnose, and L-fucose gave 67%) 93%) and 55% inhibition at 25 mM concentration, r e s p e ~ t i v e l y .Inter~~~ estingly, D-altrOSe, gentiobiose, and L-sorbose were also found to be inhibitory a t the same concentration. These studies suggest that a variety of cellular interactions may indeed be mediated by receptors with specificity for simple sugars. From our screening studies of D-mannose derivatives, previously prepared for macrophage binding and uptake ~ t u d i e s ,D-mannosides ~,~ bearing hydrophobic phenyl aglycons were found to be inhibitory a t various concentrations in the guinea pig T cell proliferation assay. Thus it was thought of interest to prepare 1-thioglycosideshaving highly functionalized cinnamyl aglycons and examine their
Chart I”
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(1) Rosenthal, A. S.; Shevach, E. M. J. Exp. Med. 1973,138,1194. (2) Rosenthal, A. S.; Barcinski, M. A,; Rosenwasser, L. J. Fed. Proc., Fed. Am. Sac. Exp. Biol. 1978, 37, 79. (3) Muchmore, A. V.; Decker, J. M.; Blaese, R. M. J. Immunol. 1980, 125, 1306. (4) Muchmore, A. V.; Blaese, R. M. In Macrophage Regulation Immunity; Unanue, E. R., Rosenthal, A. S., Eds.; Academic: New York 1980; p 505. (5) Wu, M. S.; Robbins, J. C.; Bugianesi, R. L.; Ponpipom, M. M.; Shen, T. Y. Biochem. Biophys. Acta 1981,674,19. Ponpipom, M. M.; Bugianesi, R. L.; Shen, T. Y. Can. J. Chem. 1980,58, 214. (6) Ponpipom, M. M.; Bugianesi, R. L.; Robbins, J. C.; Doebber, T. W.; Shen, T. Y. J . Med. Chem. 1981,24,1388. Robbins, J. C.; Lam, M. H.; Tripp, C. S.; Bugianesi, R. L.; Ponpipom, M. M.; Shen, T. Y. Proc. Natl. Acad. Sci. U.S.A. 1981, 78, 7294. Doebber, T. W.; Wu, M. S.; Bugianesi, R. L.; Ponpipom, M. M.; Furbish, F. S.; Barranger, J. A.; Brady, R. 0.;Shen, T. Y. J . Bid. Chem. 1982, 257, 2193.
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Ph
B : R z A c ; R‘=OMs 10: R = A c ; R ‘ = I 11: R = A c ; R’= N3 12: R = H ; R’= N3 13:R;H;R =NH2 14: R = H ; R’= NHAc 15: R:H; R‘z NHCOCH2CH2CH3 16: R = H; R‘= CO(CH&CH=CH(CH2),CH3 17: R=H; R’= NCO(CH2)4CHCH2CH2S-S L
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abilities to block the expression of T cell reactivity as measured by an in vitro antigen-specificproliferative assay and an in vivo delayed hypersensitivity. Thioglycosidic linkage was chosen because it is more stable toward acid 0 1987 American Chemical Society
706 Journal of Medicinal Chemistry, 1987, Vol. 30, No. 4
Ponpipom et al.
Table I. Proliferative Response of Cinnamyl 1-Thioglycosides ([3H]Thymidine Uptake/Acpm
X
concn, uM compd 1000 750 500 250 100 10 0 2" 0.18 f 0.06 0 f 0.04 0.04 f 0.02 17.56 f 8.65 63.65 6.89 95.87 f 2.25 82.37 f 11.30 42.05 f 2.55 3b 38.87 f 3.86 62.69 f 5.90 66.74 f 2.26 75.32 f 5.48 67.83 f 6.98 80.26 f 5.80 4b 0.06 f 0.01 1.51 f 0.01 0.02 f 0.01 5.80 f 1.59 62.13 f 3.93 93.59 f 3.54 72.80 f 9.05 31.80 f 10.33 66.62 f 8.92 5c 17.52 f 0.82 109.27 f 3.18 129.87 f 13.61 144.48 f 7.64 147.35 f 8.61 12.79 f 7.23 6d 36.42 f 6.01 5.97 f 1.92 59.68 f 7.32 101.06 f 6.78 114.88 f 7.04 93.46 f 1.17 3.85 f 0.43 7d 13.04 f 4.43 28.94 f 3.20 34.14 f 3.45 64.17 f 6.39 54.88 f 3.65 86.88 f 4.25 8C 0 f 0.1 34.23 f 7.49 18.46 f 5.42 39.73 f 7.45 59.03 f 4.69 72.81 f 5.70 70.35 f 3.90 12' 0.06 f 0.05 0 f 0.06 2.26 f 1.54 21.10 f 1.61 14.29 f 6.38 20.98 f 1.57 33.45 f 4.20 13c3e 0.01 f 0.01 0.02 f 0.01 1.23 f 0.26 71.08 f 1.37 101.31 f 9.69 81.05 f 2.32 119.89 f 9.02 14're 38.82 f 0.09 36.03 f 7.49 39.27 f 10.17 52.86 f 12.39 70.68 i 0.10 66.58 f 6.26 79.84 f 5.68 15'fe 0.07 f 0.14 0 f 0.02 0 f 0.03 1.73 f 0.79 44.98 f 10.67 68.37 f 2.28 85.76 f 2.87 16b*' 0.04 f 0.02 0.02 f 0.01 0 f 0.01 0 f 0.01 0.61 0.02 52.48 f 3.00 72.27 f 7.13 17b-e 0.08 f 0.02 0 f 0.01 0 f 0.01 Of0 2.97 f 0.50 75.25 f 6.5 93.24 f 5.48 19b 0 f 0.02 Of0 0 f 0.01 36.21 f 1.75 1.23 f 0.38 97.01 f 2.18 87.98 f 8.22 21c 0 f 0.14 0 f 0.05 0.11 f 0.77 26.66 f 7.30 66.34 f 5.47 86.52 f 5.79 89.06 f 0.16 "Tested nine times in triplicate. *Tested twice in triplicate. eTested thrice in triplicate. dTested once in triplicate. eTested as suspensions; thus the data acquired for these compounds may not be reliable. Data are shown as mean Acpm X f SD. D-Mannose and L-rhamnose, when tested by themselves with no modifications, did not block at concentrations up to 1 mM. ~~
*
*
Scheme I
Table 11. Inhibition of [3H]Thymidine Uptake by Cinnamyl
and enzymatic hydrolysis than 0-glycosides.
1-Thioglycosides (ICsO,pM)" anomeric ICBo, anomeric ICbo, compd confia LLM comDd config uM 2 a 198 7 a 340 8 a 402 3 P 871 4 01 160 12 a 240 19 a 41 5 P 525 21 a 102 6 R 750 "The guinea pig T cell proliferation assay was carried out as described in the Experimental Section. The data are expressed as concentration in pM of cinnamyl 1-thioglycosides required to exhibit 50% inhibition of maximum proliferative response.
1,9.18,20
2,8,7,19,2l
Chemistry Cinnamyl 1-thioglycosides 2, 6,7,9, 19, and 2 1 (Charts I and 11) were synthesized in good yields as outlined in Scheme I. Compounds 3-5 were prepared from cinnamyl bromide and the respective 1-thio-P-D-manno(and~ , P - L rhamno)pyranose sodium salts. In the preparation of the 6-oleamido derivative 16 from 13, a substantial amount of the 6-acetamido analogue 14 was also isolated. The formation of 14 was apparently due to the contamination of oleic anhydride with acetic anhydride. Results and Discussion In T cell proliferation assay, an enriched T cell population was derived from guinea pigs immunized with ovalbumin in complete Freunds adjuvant. Irradiated (2100 rads) exudate cells (macrophages) were used as a source of the antigen ovalbumin-presenting cells. Initially cinnamyl 1-thio-D-manno(andL-rhamno)pyranosides (2-5) were prepared and their effects on guinea pig T cell proliferation were tested by measuring the incorporation of [3H] thymidine uptake (see Experimental Section). These compounds all appeared to block [3H]thymidineuptake to various degrees (see Table I). In both cases the a anomers were more inhibitory than the corresponding 6 anomers (Table 11). Since 6-O-a-D-mannopyranosyl-Dmannose was suggested to be capable of blocking early events necessary for an antigen-specific T cell re~ponse,~ compound 7, a cinnamyl 1-thioglycoside containing this disaccharide, was thus prepared and shown to have good inhibitory activity. It was, however, less potent than the monosaccharide 2 (Table 11). Modification of the 6-OH (7) Muchmore, A. V.; Decker, J. M.; Blaese, R. M.; Nilsson, B. J. E x p . Med. 1984, 160, 1672.
group of 2 was undertaken to probe the effects of other substituents on T cell proliferation. Most of the 6-substituted analogues also have good inhibitory effects. The 6-0-methyl derivative (19) and the 6-deoxy analogue (21) appeared to be more potent than 2 and 4 (Table 11). Unfortunately, compounds 13-17 were not very soluble in the testing medium, thus their biological data may not be reliable. Cinnamyl 1-thio-P-L-fucopyranoside (6) was also found to be inhibitory, but to a lesser degree than 2 and 4. Compound 8, the saturated analogue of 2, was somewhat less inhibitory than the parent compound. DMannose and L-rhamnose, when tested by themselves without modifications, did not block T cell proliferation at concentrations up to 1 mM. The mechanism of blocking T cell proliferation is not clear. These sugar inhibitors may act on macrophages or T cells directly or they may block macrophages in presenting the antigen (ovalbumin) to T cells. Three compounds, 2, 4, and 21, have been used to pretreat macrophage and peritoneal exudate lymphocyte (PELs) populations. Experimental design was such that each cell response to the pretreatment could be observed and reversibility of the effect could be studied (see Experimental Section). The lymphocytes (PELs) represent cells passed over a nylon wool column for T cell enrichment. The macrophage population did not receive such treatment. The conditions for pretreatment were incubation at 37 "C in 5% COz for 18-20 h. The concentration of compounds used for pretreatment is indicated in Tables 111-V. Macrophages were irradiated with 2100 rads and antigen pulsing was for 1h at 37 "C with a concentration of 100 pg/mL. Data are shown as mean Acpm X Table I11 shows proliferative response of cells pretreated with 4. Ovalbumin (OVA) pulsed macrophages pretreated with 4 shows effects on both populations of peritoneal exudate
Cinnamyl 1- Thioglycosides
Journal of Medicinal Chemistry, 1987, Vol. 30, No. 4 707
Table 111. Proliferative Response" (Acpm) of Cells Pretreatedb with 4 pretreatedb PELsC PELS macrophages (Mqh) 6.67 4.75 141.55 95.34 OVA pulsed Mqhd 4 pretreated Mqh' 4.89 2.81 104.36 33.97 OVA pulsed 4 pretreated MI$ Mqh + OVA (10 pg/mL) 129.51 45.99 4 pretreated Mqh + 139.97 49.95 OVA (10 pg/mL) " [3H]Thymidine uptake was determined by liquid scintillation spectrometry, and data are shown as mean Acpm X bPretreatment of cells with 1 mM of 4 at 37 OC for 18 h. Peritoneal exudate lymphocytes. Macrophages incubated with 100 pg/mL ovalbumin at 37 OC for 1h. 'Macrophages pretreated (incubated) with 1mM 4 at 37 OC for 18 h.
Table VI. Effect of 2 and 4 Given Intraperitoneally" on Delayed Hypersensitivity Reaction in Mice dose, increase in footpad % P compd mg/kg thickness, mm X 10 reduction valueb 5.62 f 2.0 control
Table IV. Proliferative Response" (Acpm) of Cells Pretreatedb with 2 pretreatedb PELsc PELS 1.31 1.16 macrophages (Mqh) 41.36 30.35 OVA pulsed Mqhd 1.89 1.07 2 pretreated Mqh' 27.75 14.20 OVA pulsed 2 pretreated Mqh 2 pretreated Mqh + 14.50 8.70 OVA (10 pg/mL) 2 pretreated OVA pulsed Mqh + 18.94 12.06 OVA (10 pg/mL) [3H]Thymidine uptake was determined by liquid scintillation spectrometry and data are shown as mean Acpm X bPretreatment of cells with 500 pM of 2 at 37 OC for 18 h. Peritoneal exudate lymphocytes. Macrophages incubated with 100 pg/mL ovalbumin at 37 "C for 1h. 'Macrophages pretreated (incubated) with 500 pM 2 at 37 "C for 18 h.
Table VII. Effect of 2 and 4 Given Orally" on Delayed Hypersensitivity Reaction in Mice dose, increase in footpad % P compd mg/kg thickness, mm X 10 reduction valueb 1.17 f 0.18 control
Table V. Proliferative Response" (Acpm) of Cells Pretreatedb with 21 pretreatedb PELsC PELS macrophages (Mqh) 1.46 1.34 OVA pulsed Mqhd 45.43 29.03 21 pretreated Mqh' 2.26 1.62 OVA pulsed 21 pretreated Mqh 13.97 2.63 21 pretreated Mqh + 14.22 2.63 OVA (10 pg/mL) 21 pretreated OVA pulsed Mqh + 11.14 3.82 OVA (10 pg/mL) " [3H]Thymidine uptake was determined by liquid scintillation spectrometry and data are shown as mean Acpm X bPretreatment of cells with 500 pM of 21 at 37 "C for 18 h. Peritoneal exudate lymphocytes. Macrophages incubated with 100 pg/mL of ovalbumin at 37 "C for 1 h. 'Macrophages pretreated (incubated) with 500 pM of 21 at 37 "C for 18 h.
lymphocytes (PELS) (i.e., T cells that are both pretreated and untreated with 4). The effect of 4 on pretreated PELS is very significant (64%) and irreversible with addition of continuous antigen (cf. 49.95 with 95.34). The effect of 4 on PELS is significant (26% ) and reversible with addition of continuous antigen (cf. 139.97 with 141.55). Tables IV and V show proliferative responses of cells pretreated with 2 and 21, respectively. Both populations of PELS show considerable inhibition by the pretreatment with either 2 or 21 (33% and 53% for 2; 69% and 91% for 21). These effects are all irreversible with addition of continuous antigen (cf. 18.94 with 41.36, and 12.06 with 30.35 for 2; and 11.14 with 45.43, and 3.82 with 29.03 for 21). The data in Tables IV and V show that the macrophage population's ability to process antigen is significantly inhibited and irreversible. Inhibition indicates possible interference with cellular metabolism.
2
30
10 3
control 4
30
10 3
2.07 2.46 7.30 5.26 2.34 2.78 4.60
1.2 0.5 1.5 2.0 f 1.1 f 1.3 f 1.6 f f f f
63 56
0
0.005 0.005
