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J. gen. Virol. (1988), 69, 1735-1739. Printedin Great Britain 1735 Key words: LFV/PV/arenavirus Immune Serum Increases Arenavirus Replication in Monocytes By R I C H A R D M. L E W I S , * T H O M A S M. C O S G R I F F , B E V E R L Y Y. G R I F F I N , J O A N R H O D E R I C K AND P E T E R B. J A H R L I N G Medical Division and Disease Assessment Division, United States Army Medical Research Institute o f Infectious Diseases, Fort Derrick, Frederick, Maryland 21701, U.S.A. (Accepted 20 April 1988) SUMMARY The U937 monocytic cell line was used to determine whether antibodies could facilitate infection and replication of the arenaviruses, Pichinde virus (PV) and Lassa fever virus (LFV). When high dilutions of PV-immune serum were added to cultures simultaneously with PV inoculum, virus replication was dramatically (1000-fold) increased. Low dilutions of this antiserum neutralized the virus. LFV also replicated in U937 cells. The presence of LFV-specific immune serum in the growth medium increased the viral titre as much as 10000-fold. Addition of heat-aggregated IgG partially inhibited antibody-mediated enhancement, probably by inhibiting the binding of immune complexes to the monocytic cells. The arenaviruses Junin virus, Machupo virus and Lassa fever virus (LFV) are major human pathogens in South America and Africa and cause diseases characterized by haemorrhagic phenomena and high rates of mortality (White, 1972; Walker et al., 1982; Peters, 1984). The ability of immune serum to enhance the infectivity of many viruses has been welt established (Porterfield, 1986); however, this phenomenon has not been studied for arenavirus infection. Antibody-induced enhancement of viral disease was initially proposed in dengue virus infection. Halstead et al. (1973) suggested that cross-reacting antibodies might predispose individuals to the more severe forms of infection, dengue haemorrhagic fever and dengue shock syndrome. In vitro studies of this disease showed that the target cell of antibody-enhanced dengue proliferation was the mononuclear phagocyte (Halstead & O'Rourke, 1977a, b). Enhanced viral infectivity for mononuclear cells in the presence of specific antibody has also been demonstrated for other viruses (Porterfield, 1986; Cardosa et al., 1986; King et al., 1984; Burstin et al., 1983; Peiris et al., 1982; Peiris & Porterfield, 1979). Also the presence of immune serum can increase viral infectivity in monocytic cell lines (Peiris & Porterfield, 1979; Brandt et al., 1982; Peiris et al., 1982; Burstin et al., 1983; Hotta et al., 1984; King et al., 1984). The cell lines employed have been well characterized, including demonstration of Fc receptors (Peiris & Porterfield, 1979; Snyderman et al., 1977; Unkeless & Eisen, 1975; Schlesinger & Brandriss, 1981). Monocytic cells are central in the immune response to viral infection (Mims, 1986; Morahan et al., 1985 ; Mogensen, 1979) and possess important haemostatic functions (Edwards & Rickles, 1980; Levy et al., 1981; Helin, 1986). Viral interaction with monocytes might therefore be important in the pathogenesis of some of the viral haemorrhagic fevers. We have determined whether immune serum affects arenavirus infection, using the U937 cell line, the arenaviruses Pichinde virus (PV) and LFV and specific monkey immune serum. U937 cells were grown in RPMI medium (Gibco) supplemented with 10~ heat-inactivated foetal calf serum (Gibco) and 1~ each of sodium pyruvate (M.A. Bioproducts, Hagerstown, Md., U.S.A.), non-essential amino acids (Gibco), and antibiotics. The cells were cultured at 37 °C in humidified air containing 5 ~ CO2, with serial passage twice weekly. The strain of PV used in these studies was the An 4763 strain originally isolated from its natural host, Oryzomys 0000-8120 © 1988 SGM Downloaded from www.microbiologyresearch.org by IP: 88.99.165.207 On: Wed, 10 May 2017 21:25:50 Short communication 1736 Table 1. Effect of antiserum on virus titre Experiment 1 M.o.i. 1 O.l Anti-PV serum* loglo P.f.u.t J' 72 h c 48 b~ - 0 (0) + 2.72 (0.09) - 0 (0) 0 (0) + 1.03 (0"21) 1"33 (0"39) 96 h 0.8 (1.13) 5.8 (0) 0 (0) 4.47 (0.47) 1.23 (0) 4.4 (0.16) log10 P.f.u.1Experiment 2 M.o.i. 1 Heat-aggregated IgG + + Anti-PV serum* + + - r 48 h:~ 1.52 (1.09) 2.97 (0.34) 1-30 (0.92) o.oo (o) A 96 h 3.20 (0.65) 4.07 (0.09) 1.13 (1.60) 3.07 (0-12) * 1:5000 dilution. 1"Values represent average of triplicate experiments; standard deviation is shown in parentheses. Incubation time. albigularis, passaged once through hamster brain and then repeatedly through strain 13 guineapig spleens (Jahrling et al., 1981). LFV was the reference Josiah strain initially isolated from a patient and subsequently passaged four times in Vero cells. PV antiserum was obtained from a rhesus m o n k e y inoculated with virus. The monkey demonstrated no illness but developed an 80 % plaque reduction neutralization titre (PRN80) of 1:128. LFV antiserum was obtained from a rhesus monkey inoculated with LFV. This monkey recovered from a Lassa fever-like illness and developed a PRN80 titre of 1:200. Both antisera were used at a final dilution of 1:5000. For infectivity studies U937 cells were washed and pelleted in 50 ml conical tubes at 1600 g for 15 min at 23 °C. Antiserum (or normal monkey serum) and virus were diluted in cell medium, and 100 ~tl of each was added to the cell pellet. Cells, virus and antiserum were incubated at 37 °C for 60 min, washed twice in medium and resuspended in 1.5 ml at a cell concentration of 5 × 105/ml before addition to individual wells of six-well tissue culture plates. Antiserum or normal serum was again added to a final dilution of 1 : 5000. Cultures were maintained at 37 °C in air containing 5 % CO2. Samples were removed at various times and infectious virus was measured as p.f.u, on Vero cell monolayers. Samples for assay were serially diluted and added to cells, after which virus was allowed to adsorb for 60 min at 37 °C. Monolayers were overlaid with 1% agarose containing Eagle's basal medium supplemented with Earle's salts and H E P E S buffer. They were incubated at 37 °C in humidified air containing 5% CO2 for 5 days (4 days when assaying for LFV p.f.u.). At this time, 2 ml of Puck's saline A containing 1:6000 neutral red was added to the cultures. Plaques were counted after an additional incubation of 18 to 24 h. PRN80 titres were determined by both the constant serum-virus dilution method and the serum dilution, plaque reduction method (Jahrling, 1983). To determine whether immune serum would increase the production of PV in U937 cells, PVimmune serum and two concentrations of virus inoculum were added to U937 cells and the cultures were incubated and then washed to remove residual virus. The cells were resuspended in medium containing antiserum and samples were removed for virus titration after incubation at 48, 72 and 96 h (experiment 1, Table 1). After 48 h, cultures inoculated with an m.o.i, of 1 to which normal serum had been added contained no infectious virus while antiserum-treated cultures had supernatant titres greater than 102"5. The increase in virus titre in the presence of specific antiserum was noted at multiplicities of 1 and 0.1 and at all sampling times. To test the possibility that increased virus production was mediated by the binding of viral immune complexes to cellular Fc receptors, heat-aggregated IgG was used to block immune complex binding (experiment 2, Table 1). Cultures containing antiserum again showed significantly higher virus titres but addition of the IgG reduced virus titres when measured at 48 and 96 h. Downloaded from www.microbiologyresearch.org by IP: 88.99.165.207 On: Wed, 10 May 2017 21:25:50 Short communication I I I a I ~ 1737 d, "= 2 0:_~ 10 I t 100 1000 Reciprocal of antiserum dilution I I 10000 Fig. 1. U937 cells were infected with PV in the presence of antiserum. The virus titres are shown in comparisonwith the dilution of antiserum added to the respective cultures. Sampleswere taken at 96 h p.i. PV antiserum (O); normal serum (A). Fig. 1 shows that U937 cells were infected in the presence of various dilutions of PV antiserum. Serum dilutions were added to a constant number of U937 cells and virus. At the 1:10 antiserum dilution, the viral titre was less in those cultures containing normal serum, suggesting neutralization. At higher dilutions, the virus titre increased and remained at about 104. The possibility of antibody-enhanced infectivity of LFV was also tested. As shown in Fig. 2, U937 cells were capable of supporting virus replication. In the presence of antiserum, the growth of virus was dramatically increased, resulting in titres of virus increased by as much as 10000-fold. In these studies, monkey antiserum against PV markedly increased viral replication in U937 cells and heat-aggregated IgG inhibited the antibody-induced increase. Other studies of antibody enhancement in U937 cells have implicated Fc receptors in the mechanism of enhancement: only Fc receptor-bearing cells showed enhancement (Unkeless et al., 1975); F(ab')2 did not mediate increases in viral titre, and monoclonal antibody to Fc receptors blocked the antibody-induced increase (Peiris et al., 1981). Some enhancement studies have characterized individual sera for both the ability to neutralize virus at one concentration and to enhance infectivity at another lower concentration (King et aL, 1984; Hotta et al., 1984; Peiris et al., 1982; Peiris & Porterfield, 1979; Brandt et al., 1982). Replication of PV in U937 cells was diminished at high antiserum concentrations. At low antiserum concentrations, virus titres were significantly increased. This effect might have been the result of dilution of populations of neutralizing antibodies beyond their effectiveness with unmasking of populations of enhancing antibodies. Alternatively, the concentration of a single antibody population, with both neutralizing and enhancing properties, might have been the determining factor. Studies using monoclonal antibodies (MAbs) against West Nile virus showed that one of three MAbs could both neutralize virus and enhance infectivity (Peiris et al., 1982). Downloaded from www.microbiologyresearch.org by IP: 88.99.165.207 On: Wed, 10 May 2017 21:25:50 1738 Short communication a) I I I (b) I j I 0 // 0 I 48 1 72 I t 1 96 0 Time after infection (h) 1 48 I 72 1 96 Fig. 2. Cultures of U937 cells were infected with LFV at an m.o.i, of 0.1 (a) and 1 (b). Half of the cultures contained antiserum (It) and the other half contained normal serum (lq). Studies in rico have corroborated the evidence in vitro for antibody enhancement of virus replication for a number of viruses. Passive immunization of rhesus monkeys with dengue antiserum resulted in increased virus titres in transfused animals (Halstead, 1979). Mice injected simultaneously with MAb and yellow fever virus exhibited a decrease in mean time to death which was dependent on the virus strain, the particular antibody and its concentration (Barrett & Gould, 1986). In contrast, studies using antiserum to treat monkeys and guinea-pigs infected with LFV have shown a beneficial effect, with no antibody-associated increase in viraemia or decrease in survival time in either species (Jahrling, 1983; Jahrling & Peters, 1984). The present studies clearly demonstrate antibody-mediated enhancement of virus infection of U937 cells for two arenaviruses, PV and LFV. These studies tested only a single PV antiserum and a single LFV antiserum, but comparisons between sera of different titres and differences in strain specificity might help to define this phenomenon further. As with other viral infections in which immune enhancement has been demonstrated, the implications for human disease are uncertain. We thank Willis Ennis for invaluable suggestions and Molly Shepley-Stone for typing the manuscript. REFERENCES BARRETT, A. D. T. & GOULD, E. A. (1986). Antibody-mediated early death in vivo after infection with yellow fever virus. Journal of General Virology 67, 2539-2542. BRANDT,W. E., McCOWN,J. M., GENTRY, M. K. & RUSSELL,P. K. (1982). Infection e n h a n c e m e n t of dengue type 2 virus in the U-937 cell line antibodies to flavivirus cross-reactive determinants. Infection and Immunity 36, 1036-1041. Downloaded from www.microbiologyresearch.org by IP: 88.99.165.207 On: Wed, 10 May 2017 21:25:50 Short communication 1739 BURSTIN, S. J., BRANDRISS,M. W. & SCHLESlNGER, J. J. (1983). Infection of a macrophage-like cell line, P388D, with reovirus; effects of i m m u n e ascitic fluids and monoclonal antibodies on neutralization and on e n h a n c e m e n t of viral growth. Journal of Immunology 130, 2915-2919. CARDOSA,M. J., GORDON, S., HIRSCH, S., SPRINGER, T. A. & PORTERFIELD, J. S. (1986). Interaction of West Nile virus with primary murine macrophages: role o f cell activation and receptors for antibody and complement. Journal of Virology 57, 952-959. EDWARDS, R. L. & RICKLES, F. R. (1980). The role of h u m a n T cells (and T cell products) for monocyte tissue factor generation. Journal of Immunology 125, 606~609. HALSTEAD,S. B. (1979). In vivo e n h a n c e m e n t of dengue virus infection in rhesus monkeys by passively transferred antibody. Journal of Infectious Diseases 140, 537 543. HALSTEAD,S. B. & O'ROURKE, E. J. (1977a). Dengue viruses and mononuclear phagocytes. I. Infection e n h a n c e m e n t by non-neutralizing antibody. Journal of Experimental Medicine 146, 201-217. HALSTEAD, S. B. & O'ROURKE, E. J. (1977b). Antibody-enhanced dengue virus infection in primate leukocytes. Nature, London 265, 739-741. HALSTEAD,S. B., SHOTWELL,H. & CASALS,J. (1973). Studies on the pathogenesis of dengue infection in monkeys. II. Clinical laboratory responses in heterologous infection. Journal of Infectious Diseases 128, 15-22. HELIN, H. (1986). Macrophage procoagulant factors - mediators of inflammatory and neoplastin tissue lesions. Medical Biology 64, 167-176. HOTTA,H., WlLHARTA,A. S. & HOT]A, S. (1984). Antibody-mediated e n h a n c e m e n t of dengue virus infection in mouse macrophage cell lines, M k l and M m l (41802). Proceedings of the Society for Experimental Biology and Medicine 175, 320-327. JAHRLING, P. B. (1983). Protection of Lassa virus-infected guinea pigs with Lassa-immune plasma of guinea pig, primate, and h u m a n origin. Journal of Medical Virology 12, 93-102. JAHRLING, P. B. & PETERS, C. J. (1984). Passive antibody therapy of Lassa fever in cynomolgous monkeys: importance of neutralizing antibody and Lassa virus strain. Infection and Immunity 44, 528-533. JAHRLING, P. B., HESSE, R. A., RHODERICK, J. B., ELWELL, M. A. & MOE, J. B. (1981). Pathogenesis o f a Pichinde virus strain adapted to produce lethal infections in guinea pigs. Infection and Immunity 32, 771-778. KING, A. A., SANDS,J. J. & PORTERFIELD, J. S. (1984). Antibody-mediated e n h a n c e m e n t of rabies virus infection in a mouse macrophage cell line (P388D1). Journal of Generul Virology 65, 1091-1093. LEVY, G. A., SCHWART, B. S. & EDGINGTON, T. S. (1981). The kinetics and metabolic requirements for direct lymphocyte induction of h u m a n procoagulant monokines by bacterial lipopolysaccharide. Journal of Immunology 127, 357-363. MIMS, C. A. (1986). Interactions of viruses with the i m m u n e system. Clinicaland Experimental Immunology 66, 1-16. MOGENSEN, S. C. (1979). Role of macrophages in natural resistance to virus infections. MicrobiologicalReviews43, 1-26. MORAHAN,P. S., CONNOR,J. R. & LEARY,K. R. (1985). Viruses and the versatile macrophage. British Medical Bulletin 41, 15-21. PEIRIS, J. S. U. & PORTERFIELD, J. S. (1979). Antibody-mediated e n h a n c e m e n t of flavivirus replication in macrophage-like cell lines. Nature, London 282, 509-511. PEIRIS, I. S. M., GORDON, S., UNI(ELESS,J. C. & PORTERF/ELD, J. S. (1981). Monoclonal anti-Fc receptor IgG blocks antibody e n h a n c e m e n t of viral replication in macrophages. Nature, London 289, 189-191. PEIRIS, J. S. M., PORTERHELD, J. S. & ROEHRIG, J. T. (1982). Monoclonal antibodies against the flavivirus West Nile. Journal of General Virology 58, 283-289. PETERS, ¢. J. (1984). Arenaviruses. In Textbook of Human Virology,pp. 513-545. Edited by R. B. Belshe. Littleton: PSG Publishing Co. PORTERFIELD, L S. (1986). Antibody-dependent e n h a n c e m e n t of viral infectivity. Advances in Virus Research 31, 335-355. SCHLESINGER,I. J. & BRANDRISS,M. W. (1981). Growth of 17D yellow fever virus in macrophage-like line, U937: role of Fc and viral receptors in antibody-mediated infection. Journal of Immunology 127, 659-665. SNYDERMAN,R., PIKE, M. C., FISCHER, D. G. & KOREN, H. S. (1977). Biologic and biochemical activities of continuous macrophage cell lines P388D1 and J774. ]. Journal of Immunology 119, 2060-2066. UNKELESS, J. C. & EISEN, H. N. (1975). Binding of monomeric immunoglobulins to Fc receptors of mouse macrophages. Journal of Experimental Medicine 142, 1520-1533. WALKER,D. H., McCORMICK,J. B., JOHNSON,K. i . , WEBB, P. A., KOMBA-KONO,G., ELIOTT,L. H. & GARDNER, J. J. (1982). Pathologic and virologic study of fatal Lassa fever in man. American Journal of Pathology 107, 349-356. WHITE, H. A. (1972). Lassa fever - a study of 23 hospital cases. Transactionsof the Royal Society of Tropical Medicine and Hygiene 66, 390-398. (Received 27 October 1987) Downloaded from www.microbiologyresearch.org by IP: 88.99.165.207 On: Wed, 10 May 2017 21:25:50