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are still unknown, further trials are required toestablish the minimum effective dose of chlorambu-cil for maintaining remission.

It is difficult to apply the same critical standardsof appraisal when treatment success is based on

retrospective uncontrolled surveys. EHRENREICHand colleagues,10 in a retrospective survey of pa-tients with idiopathic membranous nephropathy,claim that the corticosteroid-treated group haveless renal failure, less proteinuria, and less morta-lity than untreated patients. The patients wereidentified from renal-biopsy material obtained over17 years. Although EHRENREICH et al. stress thatthe treated and control groups were comparable inage, sex, race, and duration of disease, it is immedi-ately apparent that this is not so. The control

group contained a greater proportion of elderly pa-tients and when 3 patients, diagnosed at necropsy,are assigned to the control group, the analysisbecomes distorted. Length of follow-up varied

enormously as did duration of treatment in thesteroid group. Furthermore, it was impossible to as-sess the role of cytotoxic drugs which many pa-tients received in addition to steroids. These pointsdo not undermine the possible place of corticoster-oids in membranous nephropathy, but this type ofstudy confuses rather than clarifies the issues.

However, a preliminary report of a prospectivetrial now in progress suggests that steroids maybenefit patients with membranous nephropathy.11Also, LAGRUE and his colleagues12 have shown that,in a series of patients with membranous nephro-pathy, the proportion which lost their proteinuriawas significantly higher in the chlorambucil groupthan in the placebo or azathioprine groups.The aim of any therapy is to do more good than

harm. It is important to ascertain the lowest effec-tive dose and the likely side-effects of each drug.The short-term toxic effects-opportunistic infec-tions, bone-marrow suppression, gastrointestinaldisturbances, alopecia--differ with different drugs.The possible long-term effects are more disturbing.Cyclophosphamide can cause sterility in both malesand females (the risk seems less in females).13Chromosomal abnormalities may be induced,14 andthe precise risks of mutagenesis are not known. Itis impossible, from existing data, to say whetherchlorambucil will have similar long-term effects.Certain forms of immunodeficiency are associatedwith an increase in neoplasia and, during immuno-suppression, deficient immune surveillance mayallow a malignant clone of cells to proliferate. Inrenal-transplant patients immunosuppression may

10. Ehrenreich, T., Parush, J. G., Churg, J., Garfinkel, L., Glabman, S., Gold-stein, M. H., Grishman, E., Yunis, S. L. New Engl. J. Med. 1976, 295,741.

11. Coggins, C. H. Kidney int. 1975, 8, 408.12. Lagrue, G., Bernard, D., Bariety, J., Druet, P., Guenel, J. ibid. p. 274.13. Kumar, R., Biggart, J. D., McEvoy, J., McGeown, M. G. Lancet, 1972. i,

1212.14. Nankin, H. R. Arthritis Rheum. 1974, 17, 375.

increase the incidence of lymphomas and epidermalneoplasms.15 One report strongly suggests that cv-clophosphamide may have caused acute leukæmiain 3 patients with glomerulonephritis,16 and car-cinoma of the bladder has followed cyclophospha-mide therapy for myeloma.17 Quite possibly, post-immunosuppression neoplasia is dose-related, sinceall the patients had been treated for years and thetotal dose of cyclophosphamide had been 100 g ormore.

With clearer understanding of drug actions anddisease mechanisms, it may become possible to

secure selective rather than non-specific suppres-sion of the immune system. Clearance of particu-late antigens and antigen/antibody complexes iseffected primarily by the fixed macrophages of thereticuloendothelial system, especially Kupfer cellsof the liver. These cells are probably regeneratedby monocyte precursors after phagocytosis. Certaincytotoxic drugs such as 5-fluorouracil suppressmonocyte precursors whereas others such as aza-thioprine do not.18 Conceivably, treatment with theformer type of immunosuppressant may enhancerather than suppress the disease process. However,until better treatments emerge, we should be tryingto find out which patients are likely to respond toimmunosuppressant agents. Relapse after cyclo-phosphamide therapy in S.R.N.S. is strongly associ-ated with the presence of HLA type B12: perhapsHLA typing will prove similarly predictive withother drugs. Carefully controlled trials are stillneeded to show the lowest effective dose and thebest drug for each disease. Chlorambucil looks pro-mising, but in the long-run it may prove to be nobetter than cyclophosphamide.

Interferon Therapy in ChronicHepatitis B

MANY somatic cells produce interferon as a

defence mechanism against further spread of viralinfection.19 The stimulus seems to be double-stranded R.N.A., released during replication of mostR.N.A. and D.N.A. viruses.2° Interferon does not pre-vent penetration of virus into the cell but specifi-cally inhibits translation of viral messenger p.x.Awhile host proteins continue to be manufacturednormally.21 Quite how this discrimination isachieved is unknown. Messenger R.N.A.S synthe-sised by cells exposed to interferon do move moreslowly than normal on gel electrophoresis,12 and

15. Penn, I., Halgrimson, C. G., Starzl, T. E. Transplant Proc. 1971, 3, 77316. Roberts, M. M., Bell, R. Lancet, Oct. 9, 1976, p. 768.17. Wall, R. L., Clausen, K. P. New Engl. J. Med. 1975, 293, 271.18. Souhami, R. L. Unpublished.19. Ho, M., Armstrong, J. A. A. Rev. Microbiol. 1975, 29, 13120. Carter, W. A., De Clercq, E. Science, 1974, 186, 1172.21. Falcoff, E., Falcoff, R., Leblen, B., Revel, M. Nature New Biol. 1972, 240.

145.22. Levy, H. B., Riley, F. L. Proc. natn. Acad. Sci, U.S.A. 1973, 70, 3815

1123

perhaps this represents alteration of the hostmaterial to ensure its continued translation whileextraneous, viral messenger R.N.A. is ignored. Wheninterferon was discovered in 1957,23 therapeutichopes were high; but they were dashed by the spe-cies-specificity, which limited its production for usein man, and by the fact that very large doses werenecessary to produce measurable protectiveeffects. 24 Two research teams have, however,managed to prepare quite large quantities for ther-apeutic purposes. CANTELL and his team in Finlandhave used peripheral-blood leucocytes from blood-donors, stimulated to produce interferon in vitrowith Sendai virus.25 In Belgium, DE SoMER and hiscolleagues have used a synthetic double-strandedR.N.A. to induce interferon production in culturesof human diploid fibroblasts.26 Both these prepa-rations have now been used in man and it is clearthat they can modify replication of the hepatitis-Bvirus in patients with chronic hepatitis.

In the first of these studies, leucocyte interferonwas given to four patients with HBsAg-positivechronic active hepatitis in Stanford.27 There was arapid and reproducible fall in the serum levels ofDane-particle-associated D.N.A., D.N.A. polymerase,and core antigen, all of which are thought to becomponents of the complete hepatitis-B virus parti-cle. In two cases there was disappearance of eantigen-another Dane-particle-associated productfound free in the serum of many patients withHBsAg-positive chronic hepatitis but which mayalso be a structural component of the virion.28There was a rapid return of all these markers ofviral replication to pretreatment levels after inter-feron courses of 7 and 10 days’ duration, but aftercontinuous treatment for longer than one monththe changes had persisted for at least 9 weeks inone patient and 15 weeks in another. The serumtitre of HBsAg, the outer protein coat of the virus,decreased in only two of the patients (16-fold and4-fold). In the other study,29 DESMYTER and hiscolleagues in Leuven gave a two-week course ofhuman-fibroblast interferon to one patient with

HBsAg-positive chronic active hepatitis and to twochimpanzee carriers. The most striking changeswere again found in the hepatitis-B core-antigensystem. In the patient and in one of the chimpan-zees there was a fall in the percentage of HBcAg-positive nuclei in liver biopsy specimens (asassessed by immunofluorescence), starting justafter the end of the treatment and greatest five

23 Isaacs, A., Lindenmann, J. Proc. R. Soc. B, 1957, 147, 258.24 Merigan, T. C., Reed, S. E., Hall, T. S., Tyrrell, D. A. J. Lancet, 1973, i,

56325 Jordan, G. W., Fried, R. P., Merigan, T. C. J. inf. Dis. 1974, 130, 56.26 Billiau, A., Joniau, M., De Somer, P.J. gen. Virol. 1973, 19, 1.27 Greenberg, H. B, Pollard, R. B., Lutwick, L. I., Gregory, P. B., Robinson,

W S., Merigan, T. C. New Engl.J. Med. 1976, 295, 517.28 Neuroth, A R., Trepo, C., Chen, M., Prince, A. M. J. gen. Virol. 1976, 30,

277.29 Desmyter, J., Ray, M. B., De Groote, J., Bradburne, A. F., Desmet, V. J.,

Edy, V. G., Billian, A., De Somer, P., Mortelmans, J. Lancet, 1976, ii,645.

weeks later. In the chimpanzee, whose liver tissuewas examined up to 4 months after treatment,there was then a rapid increase in the number ofpositive nuclei.An alternative to administration of interferon is

to give an interferon inducer, and PURCELL and hiscolleagues have reported their experience with onesuch compound, polyriboinosinic-polyribocytidylicacid, in two HBsAg-positive chimpanzees.3° Thechanges closely resembled those obtained with exo-genous interferon. D.N.A.-polymerase and e-antigenlevels fell sharply in both animals within 10 daysof administration of the inducer, and in one therewas a reduction in the number of core-antigen-con-taining nuclei in liver-biopsy specimens. The inten-sity of staining of HBsAg in hepatocytes also de-creased and this was associated with a slight to

moderate decline in HBsAg levels in the serum.

However, even with long-term treatment of up toseven weeks, there was no permanent depression ofviral replication: all the viral components returnedto pretreatment levels within a month of the end of

therapy.The similarity of the findings with interferon

from different sources and even with an interferoninducer suggests that the changes observed wererelated to a rise in interferon concentrations: pro-bably interferon was acting directly to prevent viralreplication. There is, however, a very close inter-relationship between interferon and the immuneresponse. Lymphocytes can produce interferon inresponse to antigenic stimulation31 and interferon,in turn, can modulate lymphocyte function andantibody production.32 The central role of immunereactivity in determining the outcome of hepati-tis-B virus infection has been stressed by severalworkers33-35 and it is possible that interferon mayhave acted by modulating antiviral immune re-

sponses. However, other attempts to use an im-munostimulant such as transfer factor have not ledto comparable changes in the pattern of expressionof the viral antigen.36 Since interferon exerts itsclearest direct antiviral effects by protecting unin-fected cells, HO37 has suggested that maintenanceof hepatitis-B virus infection in chronic active

hepatitis might require a steady stream of newly in-fected cells and that interferon, by preventing suchnew infections, suppresses total virus replication.Such a "recirculation" of virus within the liver wasa prominent feature of the EDDLESTON/WILLIAMShypothesis,38 which proposed that a defect in pro-

30. Purcell, R. H., Gerin, J. L., London, W. T., Wagner, J., McAuliffe, V. J.,Popper, H., Palmer, A. E., Lvovsky, E., Kaplan, P. M., Wong, D. C.,

31. Levy, H. B. ibid. p. 757.32. Green, J. A., Cooperband, S. R., Kilbrick, S. Science, 1969, 164, 1415.33. Braun, W., Levy, H. B. Proc. Soc. exp. Biol. Med. 1972, 141, 769.34. Dudley, F. J., Fox, R. A., Sherlock, S. Lancet, 1972, i, 723.35. Eddleston, A. L. W. F., Williams, R. ibid. 1974, ii, 1543.36. Edgington, T. S., Chisari, F. V. Am. J med. Sci. 1975, 270, 213.37. Tong, M. J., Nystrom, J. S., Redeker, A. G., Marshall, G. J. New Engl. J.

Med. 1976, 295, 209.38 Ho, M. ibid. p. 562.

1124

duction of neutralising antibody is the essentialreason for failure of viral elimination in HBsAg-positive chronic active hepatitis. Although no dra-matic clinical effects have been observed in the stu-dies reported so far-perhaps because the dose ofinterferon was too small or the period of treatmenttoo short-there are clearly other areas of interestin relation to hepatitis-B virus infection. An imme-diate practical benefit may be the reduction in in-fectivity which should parallel the fall in produc-tion of Dane particles.

Diabetes Mellitus and AutoimmunityFOR several years circumstantial evidence has

been accumulating that insulin-dependent diabetesis associated with disorders of the immune mechan-isms. A statistical association between insulin-

dependent diabetes and the organ-specific "autoim-mune" diseases, Hashimoto’s disease, perniciousanaemia, and idiopathic adrenal atrophy, has beendetected,I-4 and serological work has revealed highprevalence of humoral, organ-specific autoantibo-dies in insulin-dependent diabetes. These includeantibodies to thyroid and gastric parietal-cellcytoplasm, to intrinsic factor, and to adrenal corti-cal tissue.2-4 Schmidt’s syndrome, a combinationof adrenalitis and thyroiditis, has been reported as-sociated with insulin-dependent diabetes in nearly200 cases.5 There are also accounts of families with

multiple disorders affecting the immune mechan-isms and associated with insulin-dependent dia-betes.6 Insulitis, described by SCHMIDT in 1902,’has been reported several times in acute, rapidlyfatal cases of juvenile diabetes.8 The intensity anddistribution of the insulitis is variable and the isletsare infiltrated predominantly with lymphocytes.This insulitis has been invoked to support theautoimmune concept of diabetes, by analogy withthyroiditis and adrenalitis; but, as DoNIACH

pointed out,9 plasma cells are absent from the isletinfiltrate and there is no lymphoid-follicle forma-tion, these being features of the accepted organ-specific disorders. Cell-mediated immunity to pan-creatic elements other than insulin has been

1. Ungar, B., Stocks, A. E., Martin, F. I. R., Whittingham, S., MacKay, I. R.Lancet, 1968, ii, 415.

2. Irvine, W J., Clarke, B. F., Scarth, L., Cullen, D. R., Duncan, L. J. P. ibid.1970, ii, 163.

3. Whittingham, S., Mathews, J. D., MacKay, I. R., Stocks, A. E., Ungar, B.,Martin, F. I. R. ibid. 1971, i, 763.

4. Nerup, J. in Immunity and Autoimmunity in Diabetes Mellitus (edited byP. A. Basteme and W. Gepts); p. 149. Amsterdam, 1974.

5. Carpenter, C. C. J., Solomon, N., Silverberg, S. G., Bledsoe, T., Northcutt,R. C., Klinenberg, J. R., Bennett, I. L., Harvey, A. M. Medicine, 1964,43, 153

6. Blizzard, R. M. in Textbook of Immunopathology (edited by P. A. Miescherand H. J. Müller-Eberhard), p. 547 New York, 1969.

7. Schmidt, M. B. Munch. med. Wschr. 1902, 49, 51.8 Gepts, W. Diabetes, 1965, 14, 619.9 Doniach, I. in Immunity and Autoimmunity in Diabetes Mellitus (edited by

P. A. Bastenie and W. Gepts); p. 175. Amsterdam, 1974.

displayed by the leucocyte-migration technique inabout a third of diabetics-mainly, but not en-tirely, those with insulin-dependent diabetes.10 11

Earlier reports of humoral antibodies in dia-betics were discounted as artefacts. In 1974, how-ever, two groups reported the occurrence of islet-cell antibodies (I.C.A.) in insulin-dependentdiabetics with coexistent autoimmune disease." 13

Both groups felt it necessary to state that I.C.A.

were likely to be uncommon in diabetics, occurringonly in patients with overt autoimmunity. But thisview was soon overtaken by events. i.c.A. are nowknown to be common in newly diagnosed juvenilediabetics,14 15 their prevalence and titre fallingwith duration of the disease.15 Indeed, on p. 1097this week, Dr IRVINE and his colleagues claim thatI.C.A. can be detected in 05% of the general popu-lation. Like LENDRUM et aI.,15 the Edinburghworkers find that I.C.A. may precede the onset ofdiabetes by several years. Whether the I.C.A. are

concerned in the genesis of the diabetes andwhether they can be regarded as a marker for thecondition, remains speculative at present. TheI.C.A. reported to date are non-specific and mayreact with any or all of the islet-cell types-not justthe insulin-producing -cells. BoTTAZzo andLENDRUM16 have lately reported specific islet anti-bodies, so more precise answers may be in the off-ing. Meanwhile, BoTTAZZo and DONIACH17 havepresented an attractive hypothesis. Adopting theterminology suggested by CUDWORTH18 of types Iand II diabetes (I=juvenile-onset or insulin-depen-dent diabetes; Immaturity-onset diabetes) theyhave divided type I into IA, associated with tempor-ary I.C.A. positivity perhaps secondary to viral dis-ease of the islets, and IB associated with greaterpermanence of I.C.A. and with other, organ-specificautoimmune disorders.The discovery of the relationship between insu-

lin-dependent diabetes and certain histocompatibi-lity antigens,19 20 together with the possibility ofviral21 and immunological factors in the setioiogy,has stimulated a great deal of interest and research.In the excitement we must not forget the 3-cellitself and its apparent vulnerability. As GEPTS andhis colleagues22 have shown, at a time when the

10. Nerup, J., Andersen, O. O., Bendixen, G., Egeberg, J., Gunnarsson, R.,Kromann, H., Poulsen, J. Proc. R. Soc. Med. 1974, 67, 506.

11. MacCuish, A. C., Jordan, J., Campbell, C. J., Duncan, L J. P., Irvine.W. J. Diabetes, 1974, 23, 693.

12. Bottazzo, G. F., Florin-Christensen, A., Doniach, D. Lancet, 1974, ii, 127913. MacCuish, A. C., Barnes, E. W., Irvine, W. J., Duncan, L. J. P. ibid.

p. 1529.14. Lendrum, R., Walker, G., Gamble, D. R. ibid. 1975, i, 880.15. Lendrum, R., Nelson, P. G., Pyke, D. A., Walker, G., Gamble, D R Br.

med. J. 1976, i, 553.16. Bottazzo, G. F., Lendrum, R. Lancet, Oct. 23, 1976, p. 873.17. Bottazzo, G F., Doniach, D. ibid. Oct. 9,1976, p. 800.18. Cudworth, A. G. Br. J. Hosp. Med. 1976, 16, 207.19. Nerup, J., Platz, P., Andersen, O. O., Christy, M., Lyngsoe, J. Poulsen

J. E., Ryder, L. P., Staub Nielsen, L., Thomsen, M., Svejgaard. A. Lancet,1974, ii, 864.

20. Cudworth, A. G., Woodrow, J. C. Diabetes, 1975, 24, 345.21. Steinke, J., Taylor, K. W. ibid. 1974, 23, 631.22. Gepts, W., de Mey, J., Marichal-Pipeleers, M. Diabetologia (in the press).