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cular and pituitary hormone production in these

workers.The 2 women workers not currently using oral con-

traceptives had normal F.S.H. and L.H. results.Preliminary evaluation of the testicular-biopsy results

of the severely affected men indicated loss of spermato-gonia, with no evidence of inflammation or severe

fibrous.The 3 men not included in the comparison who had

sperm-counts of 10 million-30 million had exposuresbetween one and three years-an observation that sup-ports the notion of a direct relationship between lengthof exposure and degree of oligospermia.

DISCUSSION

Chemically reduced male infertility related to occupa-tion has seldom been reported. Lancranjan et al.3reported that lead-poisoned workers had lowered sperm-counts, decreased sperm motility, and a higher propor-tion of abnormal forms. Diminished libido and difficultyin erection and- ejaculation were also found. Kepone, anorganochlorine insecticide, severely poisoned workers inVirginia in 1975. Most of the affected workers hadsevere neurological abnormalities, and some were alsoreported to be infertile.4The chemical suspected in the present investigation to

be the cause of infertility had previously been shown toproduce sterility in animals. D.B.C.P. was shown by Tor-kelson et al. to be toxic to the testes of rats, guineapigs,and rabbits. In the rat testis it caused degeneration ofthe seminiferous tubules, increase in Sertoli cells,reduced sperm-count, and abnormal sperm morphology.Rats with these effects also showed hepatic and renaldegeneration. D.B.C.P. was found to produce these

changes through skin absorption as well as ingestion orinhalation. Faidysh et al.6 showed that D.B.c.p. damagedthe testes, liver, and kidneys of rats, but these organsregenerated in the survivors.Airborne concentrations of D.B.C.P. in the factory we

investigated are believed to be lower than the 1 p.p.m.limit recommended by Torkelson et al.5 D.B.C.P. levelsmeasured in early 1977 in the A.C.D. were 0-4 p.p.m.(averaged for an eight-hour day). These measurementswere made with personal air-sampling devices. 7Research is being continued at this plant, together

with studies in other areas. Follow-up studies of theaffected workers are being planned. Our findings haveraised a number of important issues. One is the signifi-cance of duration and intensity of exposure. Althoughall severely affected workers (group A) were, or hadbeen, production workers for at least three years. theshortest time of exposure associated with oligospermiawas only one year. Another question is whether theobserved sterility is reversible in man as it has beenshown to be in animals. Finally, since D.B.C.P. is carcino-genic in animals8 and mutagenic in bacterial systems,9the possibility of such damage in man must also be con-sidered seriously.How big a problem D.B.c.p.-induced infertility is we

do not yet know, but our communications with medicalofficers of other companies manufacturing D.B.C.P.

clearly indicate that it extends beyond the formulatingplant described here.This study would not have been possible without the support and

cooperation of the Occidental Chemical Company, Western Division,

and the Oil, Chemical, and Atomic Workers Union, Local 1-5. Wethank Dr William Palmer, Dr Louis Brahen, and Dr EdwardSmuckler for advice on pathology, Dr John Linfoot for assistance withendocrine assays, and Dr Ken Dod, Claire Lalor, and Mary Ann Gus-tavson for administrative support.

Requests for reprints should be addressed to D. W., 2521 ChanningWay, University of California, Berkeley, California 94720, U.S.A.

REFERENCES

1. Amelar, R. D., Dubin, L., Walsh, P. C. Male Infertility. Philadelphia, 1977.2. Odell, W. D., Swerdloff, R. S. West. J. Med. 1976, 124, 446.3. Lancranjan, I., Popescu, H. I., Gavanescu, O., Klepsch, I., Servanescu, M.

Archs envir. Hlth, 1975, 30, 396.4. Zavon, M. Personal communication.5. Iorkelson, T. R., Sadek, S. E., Rowe, V. K., Kodama, J. K., Anderson,

H. H., Loquvam, G. S., Hine, C. H. Toxicol. appl. Pharmac. 1961, 3, 545.6. Faidysh, E. V., Rakhmatullaev, N. N., Varshavskii, V. A. Medskii Zh.

Uzbek. 1970, 1, 64.7. Rappaport, S., Spear, R. Personal communication.9. Olson, W. A., Habermann, R. T., Weisburger, E. K., Ward, J. M., Weis-

burger, J. H. J. natn. Cancer Inst. 1973, 51, 1993.9. Rosenkranz, H. S. Bull envir. Contam. Toxicol. 1975, 14, 18.

10. Scharnweber, C., Joyner, R. Personal communication.

Hypothesis

IS PRIMARY BILIARY CIRRHOSIS AN IMMUNECOMPLEX DISEASE?

H.C. THOMAS B. J. POTTERSHEILA SHERLOCK

Department of Medicine, Royal Free Hospital, London

Summary Large immune complexes are present inthe circulation of patients with primary

biliary cirrhosis and result in the activation of comple-ment by the classical pathway. Such large complexes arecapable of producing tissue damage. The granulomatouslesions surrounding the small bile-ducts within the liverof patients with primary biliary cirrhosis and the vascu-litis, rheumatoid arthritis, and associated lesions are allcompatible with immune complex injury. It is postulatedthat such large complexes could be formed in the

vicinity of the bile-ducts by an antigen absorbed fromthe bile or biliary epithelium. Complexes reaching thesystemic circulation might be responsible for the asso-ciated extra-hepatic diseases.

INTRODUCTION

PRIMARY biliary cirrhosis is a disease of unknown

aetiology, which largely affects middle-aged women.Insidious cholestasis, usually presenting as pruritus,continues slowly to deep jaundice and ultimately liverfailure. 1-4 The disease may remain in an asymptomaticstage for many years. In the liver small bile-ducts aredestroyed and surrounded by granulomas.3 Associateddiseases include rheumatoid arthritis, arteritis, glomeru-litis, and sicca syndrome.6-9 There is a familial cluster-ing of cases 11 Serum-immunoglobulin-M (IgM) israised and over 90% of patients have a serum mitochon-drial antibody.l2 We think that primary biliary cirrhosismight be related to immune complex liver injury and weconsider how many of the features described above couldbe explained by this hypothesis.

EVIDENCE FOR THE PRESENCE OF IMMUNE COMPLEXES

The Clq-binding assays3 detected immune complexesin the serum of most patients with primary biliary cirr-

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hosis irrespective of the stage of the histological lesion.’4The complexes were both small and large, having sedi-mentation coefficients-of 8-11S and greater than 20S.The large complexes are characteristic of primary bil-iary cirrhosis; the smaller ones are also found in hepati-tis-B positive and negative chronic active hepatitis andalcohol-induced hepatitis. These small complexes are

probably related to food and commensal bacterial

antigens which are absorbed from the gut and whichaccumulate because of the liver’s phagocytic function isimpaired in various diseases.’S These small complexesare probably formed in the presence of an antigenexcess, do not fix complement, and do not thereforecause important tissue damage. We suggest that thelarge complexes, which are found in primary biliary cirr-hosis, fix complement and are responsible for tissue

damage. Large complexes of this type when injected intothe tissues of animals result in granuloma formation,16which is the characteristic lesion in the early stages ofprimary biliary cirrhosis.

There is a positive correlation between serum-IgMconcentration and the level of Clq binding of the

patient’s serum.14 This suggests that the larger com-plexes may contain antigen complexed with an IgM anti-body and raises the possibility that the macroglobulina;-mia which is characteristic of primary biliary cirrhosis"may represent a specific response to the antigen involvedin the complex formation. A response which predo-minantly involves the IgM class indicates that the

antigen is a lipopolysaccharide. The relation betweenthe serum mitochondrial antibody and the complexeshas not been determined. However, this antibody doesexist in IgM, IgG, and IgA classes. 18

It has been more difficult to demonstrate immune

complexes in the liver parenchyma. However, in the1960s Popper and his group demonstrated extracellularaggregates of immunoglobulin and complement in thelesions of patients with primary biliary cirrhosis, 19

Fig. 1--- Complement changes in primary biliary cirrhosis.

IMMUNE COMPLEXES (dq BINDING) AND COMPLEMENTCATABOLISM (dq, c3) IN CHRONIC LIVER DISEASE

*r<001.tData of Potter et al. 20

I I

P.B.C. = primary biliary cirrhosis.C.A.L.D. = chronic active liver disease.A.L.D. = alcohol-induced liver disease.

findings compatible with the deposition of immune com-plexes.

DO THESE COMPLEXES ACTIVATE COMPLEMENT?

The damaging effects of immune complexes in livertissue are mediated through the activation products ofthe third component of complement (C3) and the ter-minal components (fig. 1). Patients with primary biliarycirrhosis show a markedly increased catabolism of thethird component of complement,20 strongly suggestingcomplement activation (see accompanying table). Thedemonstration of cleavage products (C3b)21 and im-munoconglutinins (antibodies to C3b)z2 in the patient’ssera is further evidence of the activation of C3. The

markedly increased catabolism of C3 is peculiar to prim-ary biliary cirrhosis, since patients with chronic activehepatitis (hepatitis-B antigen positive and negative) andalcohol-induced liver disease have either normal or onlyslightly increased catabolism.23C3 is activated by a C3 convertase generated by either

the classical or alternative pathways of complement acti-vation. In primary biliary cirrhosis C3 is probably acti-vated by the classical pathway, since our studies showthat the catabolism of Clq, a component exclusive to theclassical pathway, is 5 times greater than normal in

primary biliary cirrhosis and either normal or onlyslightly increased in other forms of chronic liver dis-ease.23 Endotoxsemia is well recognised in patients withcirrhosis24 and might be postulated as being responsiblefor the C3 activation demonstrated in primary biliarycirrhosis. However, endotoxins activate C3 primarily bythe alternative pathway and would not lead to the in-creased Clq catabolism that we have demonstrated.

TISSUE LOCALISATION

Why do the granulomas form predominantly,although not exclusively, in the portal tracts and how dothey relate to the btle-duct damage? Immune complexesinjected into the systemic circulation result in mononuc-lear-cell infiltration of the portal tracts but not granu-loma formation.25 Furthermore, patients with systemiclupus erythematosus26 and polyarteritis nodosa,27 inwhom immune complexes are also present, have thesame mononuclear-cell infiltrate but do not show granu-lomas or bile-duct damage. Therefore it is unlikely thatthe granuloma-inducing complexes produce biliarydamage via the systemic circulation. Complexes injectedinto the biliary tree produce epithelial damage and anacute exudative lesion.28 If this insult were prolonged it

1263

might produce a lesion comparable to that found inprimary biliary cirrhosis. Immune complexes are unlike-ly to be formed within the bile and it seems more prob-able that they are produced in the wall of the bile-duc-tule or the surrounding tissue-a reaction in many waysanalogous to an Arthus reaction. An antigen absorbedfrom the bile may combine with antibody derived fromthe portal circulation and result in the formation ofcomplexes in the bile-ductular wall and interstitial spaceof the portal tracts (fig. 2). The complexes must be in

Fig. 2-Possible mechanism of bile-ductular injury in primarybiliary cirrhosis.

"optimal proportions" (equivalent proportions of

antigen and antibody) to induce granuloma formation.16The presence of the spleen as a major antibody-produc-ing organ appended to the portal circulation wouldresult in a relatively high concentration of antibody inthe portal tracts and would favour the formation of

large complexes. Another possibility is that the antibodyis formed by plasma-cells in the periportal area, thisaccords with the large numbers of IgM plasma-cells inthis area.29 Whatever the site of production of antibody,it is the formation of large complexes in the tissueswhich results in granuloma formation.

Spillover of complexes into the systemic circulation isincidental to the primary pathogenetic process but mayexplain the association of primary biliary cirrhosis withextra-hepatic conditions such as arthritis, vasculitis, andglomerulonephritis. Furthermore, a serum factor whichinhibits the mitogen responsiveness of lymphocytes ofpatients with primary biliary cirrhosis has been demon-strated3o 31 and could be attributed to circulating im-mune complexes. Such immune complexes might alsocontribute to the state of anergy which has been demon-strated in patients with primary biliary cirrhosis.32Although this hypothesis describes a possible

mechanism of bile-duct damage and granuloma forma-tion in primary biliary cirrhosis, the antigen involvedand the way in which it enters the tissues of the portalzone of the liver are unknown. The influence of geneticfactors on the handling of the antigen or the productionof antibody is also uncertain and the predilection forfemales is unexplained.Requests for reprints should be addressed to S. S.

1. Ahrens, E. H. Jr., Payne, M. A., Kunkel, H. G., Eisenmenger, W. J., Blond-heim, S. H. Medicine, Baltimore, 1950, 29, 299.

2. Sherlock, S. Gastroenterology, 1959, 31, 574.3. Rubin, E., Schaffner, F., Popper, H. Am. J. Path. 1965, 46, 387.4. Sherlock, S., Scheuer, P. J. New Engl. J. Med. 1973, 289, 674.5. Long, R. G., Scheuer, P. J., Sherlock, S. Gastroenterology, 1977, 72, 1204.6. Golding, P. L., Smith, M., Williams, R. Am. J. Med. 1973, 55, 772.7. Alarcon-Segovia, D., Diaz-Jouanen, E., Fishbein, E. Ann. intern. Med.

1973, 79, 31.8. Rai, G. S., Hamlyn, A. N., Dahl, M. G. C., Morley, A. R., Wilkinson, R.

Br. med. J. 1977, i, 817.9. Child, D. L., Mathews, J. A., Thompson, R. P. H. ibid. 1977, ii, 557.

10. Feizi, T., Naccarato, R., Sherlock, S., Doniach, D. Clin. exp. Immun. 1972,10, 609.

11. Galbraith, R. M., Smith, M., Mackenzie, R. M., Tee, D. E., Doniach, D.,Williams, R. New Engl. J. Med. 1974, 290, 63.

12. Doniach, D., Walker, G. Gut, 1974, 15, 664.13. Nydegger, U. E., Lambert, P. H., Gerber, H., Miescher, P. A. J. clin. Invest.

1974, 54, 297.14. Thomas, H. C., De Villiers, D., Potter, B., Hodgson, H., Jain, S., Jewell,

D. P., Sherlock, S. Clin. exp. Immun. (in the press).15. Thomas, H. C., MacSween, R. N. M., White, R. G. Lancet, 1973, i, 128.16. Spector, W. G., Heeson, N. J. Path. 1969, 98, 31.17. Feizi, T. Gut, 1968, 9, 193.18. Walker, J. G., Doniach, D., Roitt, I. M., Sherlock, S. Lancet, 1965, i, 827.19. Paronetto, F., Schaffner, F., Popper, H. J. Lab. clin. Med. 1967, 69, 979.20. Potter, B. J., Elias, E., Jones, E. A. ibid. 1976, 88, 427.21. Teisberg, P. Gjone, E. Clin. exp. Immun. 1973, 14, 509.22. Thomas, H. C., De Villiers, D., Sherlock, S. Unpublished.23. Thomas, H. C., Potter, B. J., Elias, E., Sherlock, S. Gut, (in the press).24. Liehr, H., Gr&uuml;n, M., Brunswig, D., Soulter, Th. Lancet, 1975, i, 810.25. Paronetto, F., Popper, H. Am. J. Path. 1966, 49, 1087.26. MacKay, I. R., Weiden, S., Hasker, J. Ann. N.Y. Acad. Sci. 1965, 124, 767.27. Gocke, D. J., Hsu, K., Morgan, C., Bombardieri, S1., Lockshin, M., Chris-

tian, C. L. Lancet, 1970, ii, 1149.28. Paronetto, F., Woolf, N., Koffler, D., Popper, H. Gastroenterology, 1962, 43,

539.29. Hadziyannis, S., Feizi, T., Scheuer, P. J., Sherlock, S. Clin. exp. Immun.

1969, 5, 499.30. Fox, R. A., Dudley, F. J., Samuels, M., Milligan, J., Sherlock, S. Gut, 1973,

14, 89.31. MacSween, R. N. M., Thomas, M. A. Clin. exp. Immun. 1973, 15, 523.32. Fox, R. A., James, D. G., Scheuer, P. J., Sharma, O., Sherlock, S. Lancet,

1969, i, 959.

Reviews of Books

Connective Tissue Diseases

GRAHAM R. V. HUGHES. Oxford: Blackwell. 1977. Pp. 226. 9.Dr Hughes, head of the department of rheumatology at Ham-

mersmith Hospital, has written a book which emphasises thehigh standard and experience of that department, attributablein no small part to his predecessor, Prof. Eric Bywaters. Thefourteen chapters on systemic lupus erythematosus, rheuma-toid arthritis, Sjogren’s syndrome, scleroderma, polymyositis,mixed connective-tissue disease, as well as vasculitic disordersincluding polyarteritis nodosa and polymyalgia rheumatica,

) are written concisely with an emphasis on clinical features anddiagnosis. In the chapter on rheumatoid arthritis for example,the reader is taken through the well established format of epi-demiology, pathology, aetiology, clinical features, systemicmanifestations, laboratory tests, differential diagnosis, and

management. One can criticise only the section on manage-ment which is dealt with sketchily and in which there is nomention of the management of joint infection in rheumatoidarthritis, a not uncommon problem after surgery or in patientsreceiving corticosteroids. However, these defects are minor

compared with the clear, factual way in which the chapters areset out. The text is liberally illustrated with clear reproduc-tions of X-rays and histopathological slides. There are no col-our plates. Some may find the price expensive for a book thissize. The last two chapters give brief details on immune com-plexes and complement as well as immunological tests in rheu-matic diseases. Here, too, one can make minor criticisms. Thealternative pathway of activation of complement and its rele-vance might have been given more space although the readeris referred to articles on the subject. Dr Hughes has supplied