Med Microbiol Immunol (1985) 1 7 3 : 2 7 9 - 2 8 9

Medical Microbiology and Immunology �9 Springer-Verlag 1985

Antibiotics and immunomodulation: Effects of cefotaxime, amikacin, mezlocillin, piperacillin and clindamycin

W. Roszkowski 1, H.L. Ko 2, K. Roszkowski I , J. Jeljaszewicz 3, and G. Pulverer 2

1 National Institute of Lung Diseases and Tuberculosis, Warsaw, Poland 2 Institute of Hygiene, University of Cologne, Federal Republic of Germany 3 National Institute of Hygiene, Warsaw, Poland

Abstract . The effects of 7 days' chemotherapy on the humoral and cellular para- meters of the host immune system are described. In Balb/c mice the effects of cefotaxime, amikacin, mezlocillin, piperacillin and clindamycin were examined.

The delayed-type hypersensitivity reaction, as well as the lgM and lgG responses, were suppressed by four of the five drugs tested: cefotaxime, amikacin, mezlo- cillin and piperacillin. One to two weeks after completion of chemotherapy with cefotaxime and amikacin, these parameters returned to normal values, whereas the mezlocillin- or piperacillin-modified reactions were still suppressed after 20 days. The concanavalin A and lipopolysaccharide-induced proliferative activi- ties of mouse spleen cells were suppressed, especially by mezlocillin. The possi- ble consequences of the immunomodulat ing effects of antibiotics for antimicro-

bial chemotherapy are discussed.

Introduction

Chemotherapy of bacterial infections can no longer be regarded as a simple interaction between drugs and bacteria. Undoubtedly the immune system of the host is also strong- ly involved in this interaction. A triangle of three equally important factors is responsi- ble for the effectiveness of chemotherapy: the bacterium, the chemotherapeutic drug used, and the host. Recent interest in the effects of antibiotics on the host 's defenee system has already resulted in several publication [4, 7, 9, 11]. However, apart from tetracyclines and rifampin, the effects of which on different parameters of the immune system are well documented [5, 10, 14 -16] , most antimicrobial drugs are still either not completely characterized or the results are contradictory. Most of these studies have been performed in vitro; only a few reports have been published on in vivo effects of antibiotics on the immune system. Unfortunately, these reports are based on the im- munopharmacological effects of single drug administrations (one-shot therapy). Our

Offprint requests to: Prof. Dr. G. Pulverer, Hygiene-Institut der Universit/it, Goldenfelsstrafle 19--21, 5000 K61n 41, Federal Republic of Germany

280 W. Roszkowski et al.

present s tudy was undertaken to evaluate the interaction of prolonged chemotherapy with different parameters of the host immune system. Five broad-spectrum antibiotics, widely used in medicine, were selected: cefotaxime, amikacin, mezlocillin, piperacillin, and clindamycin. To bring our experiments on the consequences of bacterial chemo- therapy as close to medical practice as possible, a 7-day t reatment model was chosen for our in vivo tests.

Material and methods

Antibiotics. These were cefotaxime (Hoechst AG, Frankfurt , FRG, lot no. 609), ami- kacin (Grfinenthal GmbH, Stolberg, FRG, lot no. C 2099-083) , mezlocillin (Bayer AG, Wuppertal, FRG, lots GN 585K and HW 563M), piperacillin (Cyanamid GmbH, Mfin- chen, FRG, lot no. 26150) and clindamycin (Upjohn, Heppenheim FRG, lots 83E06 and 672T). These antibiotics were injected subcutaneously into groups of mice (5 mice each) twice a day at lO-h intervals for 7 consecutive days. The dosages of the antibiotics were calculated on a per kilogram body weight basis from human therapeutic dosages. The antibiotics were used in the following daily doses: cefotaxime - 20 mg, 40 mg, 60 mg/kg body wt. ; amikaein - 5 mg, 10 mg, 15mg/kg body wt.; mezlocillin - 85 mg, 215 mg, 285 mg/ky body wt.; piperacillin - 65 mg, 130 mg, 265 mg/kg body wt.; clindamyein - 10 mg, 20 mg, 35 mg/kg body wt. The mice in the control group always received equal volumes of 0.9% saline. In in vitro experiments these antibiotics were added to cell suspensions in the following concentrations: cefotaxime - 160/ag/ml, 80 ~g/ml, 8/ag/ml; amikacin - 100 ug/ml, 50/~glml, 25 ~tg/ml; mezloeillin -- 400 ~glml, 150/ag/ml, 20/ lg /ml ; piperacillin -- 100/ag/ml, 50/2g/ml, 10/~g/ml; clindamycin -- 6/a/ ml, 3/2g/ml, 1/ lg/ml. The concentrations of these antibiotics are comparable to those observed in human blood serum after therapeutic doses.

Animals. Inbred male Balb/c mice, 8 - 1 2 weeks old, obtained from the Central Insti tute of Experimental Animals (Hannover, FRG), were used throughout the experiments. The animals were kept in plastic cages and allowed free access to food and water.

Delayed type of hypersensitivity to oxazolone. Mice (5 animals per group) were im- munized by painting 0.1 ml of a 3% solution of oxazolone (2-ethoxymethylene-4phenyl- oxazolone, Sigma, Mfinchen) in 70% ethanol on the shaved skin of the abdomen. The thickness of each ear was measured with an Oditest micrometer (H.C. Kr6plin GmbH, G6ttingen) 5 days after sensitization and both sides of the ears were then smeared with 20 /al of the oxazolone solution. The thickness of the ears was measured again 24 h after the challenge and the results are expressed as mean increases in ear thickness in units of 10 -3 cm. The control mice received the challenge only. Priming for delayed hyper- sensitivity to oxazolone was performed the day after the last injection of the antibiotic and also 8, 12, 16 and 20 days later. In other experiments, antibiotics were given to animals from the day of oxazolone sensitization until the oxazolone challenge. In this case mice received only 5 days' antibiotic treatment.

Humoral response. The control mice and the mice treated with antibiotics (5 animals per group) were immunized with 2 x 108 sheep red blood cells (SRBC), given intra-

Antibiotics and immunomodulation 281

peritoneally 4 or 7 days before the experiments. The maximal number of direct and indirect plaques was produced on the 4th and 7th day after immunization respectively. The spleen cell suspension was prepared as described below. The cells were washed and suspended in Hanks solution containing 0.5% gelatine to a concentration of 2 x 107 cells/ml. The washed sheep erythrocytes were adjusted to 20% v/v in Hanks saline. The plaquing mixture consisted of 150/21 spleen cell suspension, 20/21 SRBC, and 20 #1 fresh guinea-pig complement diluted 1:10 in PBS. For indirect plaques (IgG) 20/21 rabbit anti-mouse IgG antibodies was added instead of Hanks saline. The mixtures thus prepared were placed in Cunningham chambers and incubated for 1--1.5 h at 37~ The number of plaques was first calculated for each chamber and then for 108 spleen cells. In other experiments 10/21 of the antibiotics examined was added to the above plaquing mixture to establish the direct effect on antibody release. The humoral re- sponse was evaluated in animals treated for 7 days with antibiotics the day after the last injection of the drug and also 8, 12, 16, and 20 days later.

Lymphocyte proliferation. The animals were killed by cervical dislocation the day after the last injection of the antibiotics. The spleens were removed aseptically and pressed through a steel sieve. The suspension obtained was left to stand for 5 min in tubes to sediment fragments of tissue residues. The suspension was washed twice in Hanks saline and finally resuspended to the desired concentration in RPMI 1640 (Gibco Lab., Karlsruhe) containing 10% heat-inactivated fetal calf serum (Gibco Lab.). Cell viability was evaluated with trypan blue exclusion. The viability of all suspensions used for the experiments was higher than 85%. The cell suspension (2 x 105 cells/0.2 ml) was cultivated in a microeulture system in an atmosphere of 5% CO 2 for 72 h. Concanavalin A (1 #g/culture ; Calbiochem Ltd., Frankfurt/M) was added as a stimulant of lymphocyte proliferation. Eighteen hours before the cultures were terminated, 1 #Ci tritium-labelled thymidine (3H-TdR, 25 mCI/mmol, Amersham) was added to each culture. The in- corporation of 3 H-TdR into acid-insoluble material was determined in a liquid scintilla- tion spectrometer. The same technique was used when lipopolysaccharide (LPS) (5 #g/ ml; Calbiochem Ltd.) was added instead of Con A.

In other experiments 10/21 of the antibiotics tested was added to triplicate cultures to establish their influence on lymphocyte proliferation in vitro. Antibiotics were pre- sent through the whole period of culture (72 h). In these experiments lymphocytes were obtained from mice not treated with antibiotics.

Results

As shown in Table 1, four of the antibiotics tested produced a differently pronounced suppression of delayed-type skin hypersensitivity (DTH). The strongest inhibiton of cellular immune reaction was observed after treatment with mezlocillin and piper- acillin. Clindamycin was the only antibiotic which did not change the response of the animals to the oxazolone challenge. Similar effects of the antibiotics on DTH were observed when the drugs were given between sensitization and challenge with oxazo- lone.

The suppression of DTH induced by the highest antibiotic doses given lasted for different periods of time (Table 2). Normalization of the response to the oxazolone

2 8 2 W. R o s z k o w s k i e t a l .

T a b l e 1. E f f e c t o f a n t i b i o t i c s o n d e l a y e d - t y p e sk in

h y p e r s e n s i t i v i t y t o o x a z o l o n e

Inc rease in ea r t h i c k n e s s ( in u n i t s o f 10 -3 c m ) m e a n va lue +- SD

T r e a t m e n t b e f o r e T r e a t m e n t a f t e r

s e n s i t i z a t i o n t o s e n s i t i z a t i o n t o

o x a z o l o n o x a z o l o n

C o n t r o l (sa l ine) 1 4 . 4 +- 0 . 6 14 .4 -+ 0 . 6

C e f o t a x i m e

0 . 4 m g / d a y l l A +- 0 A a 11 .1 +- 0 .5 a

0 . 8 r a g / d a y 11 .2 _+ 0 , 4 a 11 .1 • 0 . 4 a

1 . 2 r a g ] d a y 1 0 . 9 _+ 0 .5 a 1 0 . 8 • 0 , 4 a

A m i k a c i n

0 . 1 r a g ] d a y 1 2 . 8 • 0 .5 1 3 . 4 -+ 0 . 6

0 . 2 r a g / d a y 11 .2 • 0 .5 a 8 . 6 +- 0 , 3 a

0 . 3 m g / d a y 1 0 . 8 • 0 .3 a 8 .5 • 0 . 4 a

Mezloc i l l in

1 . 7 m g / d a y 9 . 6 • 0 . 4 a 9 .8 -+ 0 , 4 a

4 . 3 r a g / d a y 7 . 5 +_ 0.3 a 7 .2 • 0 .3 a

5 . 7 r a g / d a y 6 . 2 -+ 0 . 2 a 7 .1 + 0 .3 a

P ipe rac i l l i n

1 . 3 m g / d a y 11 .3 • 0 .5 a 1 1 . 0 • 0 . 4 a

2 . 6 r a g / d a y 1 0 . 6 -+ 0 . 4 a 1 0 . 9 • 0 . 4 a

5 . 3 r a g / d a y 9 . 2 + 0 . 4 a 9 . 4 • 0 . 4 a

C l i n d a m y c i n

0 . 2 r a g / d a y 1 4 . 8 +- 0 .7 1 4 . 2 • 0 , 6

0 . 4 r a g / d a y 1 5 . 0 -+ 0 .8 14 .7 *- 0 .7

0 . 7 r a g / d a y 15 .2 -+ 0 . 8 14 .2 +- 0 .7

a P < 0 .01

T a b l e 2. D e l a y e d h y p e r s e n s i t i v i t y t o o x a z o l o n in m i c e t r e a t e d w i t h a n t i b i o t i c s : r e c o v e r y

(% o f i n h i b i t i o n )

P e r c e n t a g e i n h i b i t i o n

D a y s C e f o t a x i m e A m i k a c i n Mezloc i l l in P ipe rac i l l in

a f t e r c o m p l e t i o n (1 .2 m g / d a y ) (0 .3 m g / d a y ) (5 .7 m g / d a y ) (5 .3 m g / d a y )

o f t r e a t m e n t

8 2 8 a 15 a 57 a 38 a

12 5 3 39 a 32 a

16 0 0 2 6 a 25 a

2 0 0 0 25 a 12 a

a = P < 0 . 0 1

A n t i b i o t i c s and i m m u n o m o d u l a t i o n

Table 3. Primary humoral response to SRBC (IgM) of mice treated with different concentrations of antibiotics

DPFcb/ Io 8 spleen cells X 103 (mean value +- SD) % of inhibition

Control 1 (saline) 6.25 • 0.72 0

Cefotaxime 1.2mg/day 0.78 + 0.8mg/day 3.25 • 0.4mg/day 5.50 •

Amikacin 0.3mg/day 3.00 + 0.2mg/day 4.35 -+ 0.1mg/day 6.75 +-

Mezlocillln 5.7mg/day 0.00 a' 4.3mg/day 0.00 a 1.7rag/day 0.00 a

0.19 a 88 0.38 a 48 0.64 12

0.26 a 55 0.31 a 31 0.54 0

100 100 100

Control 2 (saline) 7.30 • 0.79 0

Piperacillin 5.3mg/day 3.25 • 0.38 a 56 2.6mg/day 4.12 • 0.33 a 44 1.3rag/day 5.00 • 0.38 a 32

Clindamycin 0.7mg/day 6.73 • 0.54 8 0.4mg/day 7.15 • 0.72 3 0.2rag/day 7.41 + 0.64 0

a P < 0.01 b DPFC = direct plaque forming cells

Data derived from different experiments. Control 1 was used for evaluating the effects of cefotaxime, amikacin and mezlocillin, control 2 for piperaeillin and clindamycin

283

chal lenge was observed in c e f o t a x i m e and amikac in g roups 12 days a f te r the c o m p l e t i o n

o f t r e a t m e n t . With mez loc i l l in and piperaci l l in 20 days a f te r the last a d m i n i s t r a t i o n of

t he drugs t he an imals were still m o r e or less i m m u n o s u p p r e s s e d .

Similar ly , all t he an t ib io t i c s tes ted , e x c e p t for c l i ndamyc in , a f fec ted the h u m o r a l

responses (Tables 3 and 4). C e f o t a x i m e and amikac in did n o t p roduce any s igni f icant

e f fec t in the l owes t doses used in our e x p e r i m e n t s , whereas mezloc i l l in admin i s t e r ed

in all t h r e e doses c o m p l e t e l y e l imina t ed the IgM and IgG responses . The i nh ib i t i on in-

duced by piperaci l l in was also observed in all dosages, b u t i t was less p r o n o u n c e d as

c o m p a r e d wi th mezloci l l in .

As s h o w n in Tables 5 and 6, the mez loc i l l in - induced suppress ion of h u m o r a l respons-

es was long-last ing, be ing still p r e s en t 20 days a f te r the c o m p l e t i o n of c h e m o t h e r a p y .

284

Table 4. Humoral response to SRBC (lgG) of mice treated with different concentrations of antibiotics

1PFCb/108 spleen cells X 103 Percentage (mean value +- SD) inhibition

Control 1 (saline) 9.72 +- 0.88 0

Cefotaxime 1.2mg/day 4.65 +- 0.51 a 53 0.8mg/day 6.32 -+ 0.59 a 35 0.4mg/day 8.91 -+ 0.76 8

Amikacin 0.3mg/day 5.94 -+ 0.68 a 39 0.2mg/day 6.71 -+ 0.56 a 31 0.1mg/day 10.19 +- 0.97 0

Mezlocillin 5.7mg/day 0.00 a 100 4.3mg/day 0.83 +- 0.11 a 92 1.7mg/day 1.34 -+ 0.16 a 87

Control 2 (saline) 8.93 -+ 0.92 0

Piperacillin 5.3mg/day 4.24 -+ 0.51 a 53 2.6mg/day 5.00 -+ 0.48 a 44 1.3mg/day 6.15 -+ 0.69 31

Clindamycin 0.7rag/day 8.04 -+ 0.75 10 0.4mg/day 8.69 -+ 0.88 0 0.2rag/day 9.12 -+ 1.02 0

a P < 0.01 b IPFC = indirect plaque forming ceils

Data derived from different experiments. Control 1 was used for evaluating the effects of cefotaxime, amikacin and mezlocillin, control 2 for piperacillin and clindamycin

W. Roszkowsk i et al.

Moreover , in animals t r ea t ed wi th this an t ib io t i c , a s igni f icant r e d u c t i o n in spleen we igh t

was n o t e d (30 m g in mez loc i l l in - t r ea ted mice in c o m p a r i s o n to 100 m g in con t ro l s ) .

I t seems i m p o r t a n t t h a t we did n o t no t i ce signs o f t ox i c i t y such as d i a r rhoea or a signi-

f i can t r e d u c t i o n o f b o d y weight . However , we observed a loss of ha i r in the ma jo r i t y

o f an imals t r e a t e d wi th all doses of mezloc i l l in t r ied.

N o n e o f t he an t ib io t i c s t e s t ed (even in t he h ighes t c o n c e n t r a t i o n used) i n f luenced in

v i t ro t he n u m b e r o f p l aque - fo rming cells w h e n t he cells were o b t a i n e d f r o m u n t r e a t e d

d o n o r s (da ta n o t shown) . Spleen ceils o b t a i n e d f r o m an imals t r e a t ed wi th an t ib io t i c s

were also e x a m i n e d fo r t he i r p ro l i fe ra t ive abi l i ty (Tab le 7). C l i n d a m y c i n did n o t a f fec t

t he l y m p h o c y t e t r a n s f o r m a t i o n i n d u c e d b y Con A or LPS. The o t h e r an t ib io t i c s p roduc -

ed a d i f f e ren t ly p r o n o u n c e d i n h i b i t i o n o f l y m p h o c y t e p ro l i f e r a t ion : c e f o t a x i m e and

Ant ib io t ics and i m m u n o m o d u l a t i o n

Table 5. Humorat response to SRBC (IgM) in mice treated with antibiotics: recovery

285

Percentage in hibition

Days Cefotaxime Amikacin Mezlocillin Piperacillin after completion (1.2mg/day) (0.3mg/day) (5.Tmg/day) (5.3mg/day) of treatment

8 19 a 11 100 a 48 a 12 0 0 100 a 46 a 16 15 0 67 a 25 a 20 nd nd 40 a 12

a = P < 0.01

DPFC/IO 8 spleen cells • 103 in mice treated with antibiotics Percentage inhibition =

DPFC/IO 8 spleen ceils • 103 in controls (saline)

DPFC = direct plaque forming cells nd= not tested

X 100

Table 6. Humoral response to SRBC (IgG) in mice treated with antibiotics: recovery

Percentage inhibition

Days Cefotaxime Amikacin Mezlocillin Piperacillin after completion (1.2 mg/day) (0.3 mg/day) (5.7 mg/day) (5.3 mg/day) of treatment

8 10 19 a 93 a 46 a 12 0 0 85 a 30 a 16 3 0 74 a 22 a 20 nd nd 49 a 4

a P < 0 . 0 1

Percentage inhibition -

nd = not tested

IPFC/108 spleen cells • 103 in antibiotic treated mice

IPFC/108 spleen cells X 103 in controls (saline) x 100

amikacin were ef fec t ive only in the highest doses tes ted ; piperaci l l in- induced inhibi t ion

was seen in all dosages; the m o s t p r o n o u n c e d ef fec t was observed in spleen-cell cul tures

f r o m animals t r ea ted wi th mezloci l l in , where the l y m p h o c y t e prol i fera t ion was com-

ple te ly b locked .

When the ant ib iot ics were added to cul tures o f l y m p h o c y t e s ob ta ined f rom un t r ea t ed

animals, only mezloci l l in and piperacil l in signif icantly reduced the prol iferat ive respons-

es to Con A and LPS. Cefo tax ime , amikacin and c l indamycin did no t inf luence the pro-

l i ferat ion even at high concen t r a t ions (Table 8, only Con A data shown) .

286 W. R o s z k o w s k i et al.

Table 7. Proliferation of spleen lymphocytes from mice treated with different concentration of antibiotics

Con A LPS

cpm/lO 6 cells cpm]lO 6 cells mean value • SD mean value -+ SD (% of control) (% of control)

Control 1 (saline) 31 880 • 2 826 (100%) 6 325 • 596 (100%)

Cefotaxime 1.2rag/day 16 271-+ 1 732 ( 5 1 % ) a 2 6 3 0 • 281 ( 4 1 % ) a 0.8rag/day 26 731 • 2 334 ( 8 4 % ) 5 710 • 625 ( 9 0 % ) 0.4mg/day 30 220 • 2 983 ( 9 5 % ) 6 948 • 712 (110%)

Amikaein

0.3rag/day 28 716 • 2 146 ( 9 0 % ) 3 015 +- 286 ( 4 8 % ) a 0.2mg/day 32 330 • 2 865 (101%) 6 951 • 610 (110%) 0.1rag/day 37 990 • 3 012 (119%) 6 743 • 592 (106%)

Mezlocillin 5.7rag/day 40 • 18 ( 0%) a 57 • 22 ( 0%) a 4.3mg/day 51 • 23 ( 0%) a 32 + 18 ( 0%) a 1.7mg/day i 618 • 215 ( 5%) a 431 • 51 ( 7%) a

Control 2 (saline) 26 441 • 1 952 (100%) 10 112 • 864 (100%)

Piperacillin 5.3rag/day 8 390 • 1 124 ( 3 2 % ) a 4 213 • 623 ( 4 2 % ) a 2.6rag/day 10 237 + 1 206 ( 3 9 % ) a 4 906 • 528 ( 4 9 % ) a 1.3rag/day 13 111 s 1 175 ( 5 0 % ) a 6 713 +- 718 ( 6 6 % ) a

Clindamycin 0.Tmg/day 28 511 • 2 162 (108%) 11 316 +- 1 018 (1125) 0.4rag/day 27 090-+ 2 312 (103%) 10 042 + 985 ( 9 9 % ) 0.2rag/day 27 311 • 2 473 (103%) 11 923 -+ 874 (118%)

a P < 0.01

Con A = concanavalin A; LPS = lipopolysaccharide.

Data derived from different experiments. Control I was used for evaluating the effects of cefo- tax• amikachl and mezlocillin, control 2 for piperacillin and clindamycin

Antib io t ics and i m m u n o m o d u l a t i o n

Table 8. Proliferation of mouse spleen lymphocytes exposed in vitro to different concentrations of antibiotics

Con A cpm/106 cells • SD (% of control)

Control (saline) 27 350 • 2 453 (100%)

Cefotaxime 160 ~tg/ml 25 o15 -+ 1 962 (91%)

80/~g/ml 25 308 -+ 2 11o (93%) 8/ug/ml 28 020 +- 2 246 (lO2%)

Amikacin 100 tzg/ml 25 300 -+ 1 863 (93%)

50/~g/ml 26 400 + 2 158 (97%) 25#g/ml 26 900+- 1 993 (98%)

Mezlocillin 400#g/ml 1 480 • 264 ( 5%) a 150#g/ml 3 710 -+ 416 (16%) a

20/~g/ml 12 400 +- 986 (45%) a

Piperacillin lO0#g/ml 6 325 • 714 (23%) a

50 tzg/ml 14 180 +- 1 672 (52%) a lOgg/ml 18 167+- 1 654 (66%) a

Clindamycln 6 t~g/ml 27 132 +- 2 352 (100%) 3/~g/ml 27 448 + 2 156 (100%) 1/zg/ml 27 392 -+ 1 963 (100%)

a P < O.Ol

287

Discussion

The results of our in vivo exper iments show tha t four o f the five antibiot ics tested may

inf luence the cellular and humora l immune responses when given for 7 consecut ive days. This part icular t iming of the t r ea tmen t was chosen on the assumption that it relates to

the usual t ime of ant imicrobial therapy in medical pract ice ( 1 - 2 weeks). Doses of the

ant ibiot ics used in this s tudy were calculated on a per ki logram of body weight basis

f rom those used in human therapy. We realize, however , that this regimen of t r ea tment

canno t imi ta te real therapeut ic condi t ions, because a faster metabol i sm of the drugs can

be expec ted in mice. It is thus l ikely that the pharmacologica l exposure o f mice in our exper iments was even less intensive than tha t of humans under real therapeut ic condi-

t ions. With regard to mezloci l l in , we know that serum level concent ra t ions in Balb/c

mice after the adminis t ra t ion of the highest dose tested are one-third of those observed

in humans after the appl icat ion o f the same dose calculated on a per ki logram body

weight basis [13].

The mos t striking finding of our s tudy is in our opin ion the p o t e n t and long-lasting

suppressive e f fec t of two penicillins, namely mezloci l l in and piperacillin. A m o n g the

ant ibiot ics inhibi t ing microbial cell-wall synthesis, the penicill ins are believed to be

288 W. Roszkowski et al.

neutral for the immune function: However, this opinion is mainly based on in vitro ex- periments [1, 3]. In our s tudy mezlocillin and piperacillin inhibited both the cellular and humoral responses. Moreover, both drugs impaired the proliferative activity of lympho- cytes. This lat ter effect was also observed when the cells were exposed to the antibiotics only in vitro, though the degree of inhibition was less pronounced than in cultures ob- tained from animals treated in vivo. On the other hand Banck and Forsgren [1] did not observe any inhibition effect of aminobenzylpenicill in, benzylpenicillin or carbeni- cillin on the lymphocyte transformation. This indicates that even small differences in the molecular formula of penicillins are of great importance for their immunopharma- cological effects. It has to be emphasized that mezlocillin significantly reduced spleen weight and evoked in treated animals a loss of hair which may also be related to the antiproliferative proper ty of this antibiotic.

Suppression of cellular and humoral immunity was also observed after 7 days ' t reatment with cefotaxime and amikacin. However, the degree of inhibition was not as strong as after the application of mezlocillin and piperacillin. Moreover, the normaliza- tion of the immune reactivity was faster. Gillissen [6] observed that cephalosporins en- hanced the IgM response to SRBC when up to 30 mg/kg was injected in a single dose. In our studies cefotaxime was also given in a dose of 30 mg/kg but this dose was repeat- ed twice a day for 7 consecutive days. There is no discrepancy between our results and those obtained by Gillissen. It is well known that single and multiple injections of the same drug can even induce opposite pharmacological effects, as was found with ampho- tericin B [2, 8, 12].

Our aim in this s tudy was to evaluate the immunopharmacological effects of drugs in condit ions similar to those in chemotherapy. Nevertheless, our results cannot be re- garded as final clinical conclusions due to the animal and experimental models. Further studies are planned on human volunteers.

References

1. Banck G, Forsgren A (1979) Antibiotics and suppression of lymphocyte function in vitro. Antimicrob Agents Chemother 1 6 : 5 5 4 - 5 6 0

2. Blanke TJ, Little JR, Shirley SF, Lynch RG (1977) Augmentat ion of murine im- mune responses by amphotericin B. Cell lmmunol 3 3 : 1 8 0 - 1 9 0

3. Dam WC, Malkinson FD, Gewurtz H (1975) The effect of common antibiotics on lymphocyte transformation. Experientia 31 : 375--376

4. Finch R (1980) Immunomodulat ing effects of antimicrobial agents. J Antimicrob Chemother 6:691--699

5. Forsgren A, 8chmeling D, Quie PG (1974) Effects of tetracyclines on phagocytic function of human leukocytes. J Infect Dis 130:422

6. Gillissen GJ (1982) Influence of cephalosporins on humoral immune response. In: Eickenberg HL, Hahn H, Opferkuch W (eds) The influence of antibiotics on the host-parasite relationship. Springer-Verlag, Berlin, Heidelberg, New York, pp 5 - 1 1

7. Hauser WE, Remington JS (1982) Effect of antibiotics on the immune response. Am J Med 7 2 : 7 1 1 - 7 1 6

Antibiotics and immunomodulation 289

8. Little JR, Blanke TJ, Valeriote F, Madolff G (1978). Immunoadjuvant and anti- tumor properties of amphotericin B. In : Chirigos MA (ed) Immune modulation and control of neoplasia by adjuvant therapy. Raven Press, New York, pp 381-387

9. Milatovic D (1983) Antibiotics and phagocytosis. Eur J Clin Microbiol 2:414-425 10. Paunescu E (1970) In vivo and in vitro suppression of humoral and cellular im-

munological response by rifampicin. Nature 228:1188-1190 11. Peterson PK (1982) How antibiotics augment host defenses. Eur J Clin Microbiol 1:

335-337 12. Roselle GA, Kauffman CA (1980) Amphotericin B and 5-fluorocytosine effect on

cell-mediated immunity. Clin Exp Immunol 40:186--192 13. Roszkowski K, Ko HL, Roszkowski W, Jeljaszewicz J, Pulverer G (1984) Effect

of some antibiotics on sarcoma L-1 tumor growth in mice. Zentralbl Bakteriol Mikrobiol Hyg [A] (in press)

14. Roszkowski W, Lipinska R, Roszkowski K, Jeljaszewicz J, Pulverer G (1984) Rifampicin induced suppression of antitumor immunity. Med Microbiol Immunol 172:197--205

15. Thong YH, Ferrante A (1979) Inhibition ofmitogen-induced human lymphocyte proliferative response to tetracycline analogues. Clin Exp lmmunol 35:443--446

16. Thong YH, Ferrante A (1980) Effects of tetracycline treatment on immunological responses in mice. Clin Exp lmmunol 39:728--732

Received June 22, 1984