Immunology Today, vol. 4, No. 10, 1983
274 et al., unpublished observations). At the
time of clinical onset of disease, there was a marked increase in the a m o u n t of antiacetylcholine receptor antibodies. T h e production of autoantibodies is certainly not equivalent to having an a u t o i m m u n e disease. Thus, all individuals carry low amounts of different autoantibodies 6'7, possibly due to polyclonal B-lymphocyte activation (including self-reactive cells) primarily by bacterial products 8. Furthermore, increased amounts of autoantibodies directed against islet cells~ and acetylcholine receptor protein 9 have been observed in healthy relatives of patients with insulin-dependent diabetes mellitus and myasthenia gravis, respectively. T h e frequencies of relatives having autoantibodies were far too high to imply that all affected individuals would later develop a clinically overt a u t o i m m u n e disease. Although the role of different autoantibodies is still a matter of debate in a n u m b e r of a u t o i m m u n e disorders, there is strong evidence that immunoglobulins directed against acetylcholine receptor protein have pathogenic importance in myasthenia gravis ~°. T h e above data are thus compatible with the view that at least some of the etiological steps in the a u t o i m m u n e disease process take place several years before the disease becomes clinically manifest. T w o observations argue in favour of an even longer time interval between the initial phase and the overt disease. O n e concerns the finding of anti-islet cell antibodies in individuals later developing insulin-dependent diabetes mellitus. In these individuals the autoantibodies were already present in the first serum sample tested ~'2 and it may well be that they had appeared much earlier. T h e other concerns the cell interactions in the a u t o i m m u n e process. It is our belief that in the majority of autoi m m u n e diseases, the autoantibody production is T-cell dependent. Thus, it is possible that the activation of autoreactive T lymphocytes precedes that of B cells. However, when T- and B-lymphocyte reactivity is studied after immunizations, in the majority of cases they parallel each other, and there is no obvious reason to believe that the kinetics of a u t o i m m u n e reactions would differ. T h e idea that there is a long time inter-
val between the initial etiological steps and the manifest autoimmune disease certainly raises the question W h a t takes place in the interval? However, irrespective of the answer to that question, the mere possibility per se namely, that the autoimmune reaction started several years before the disease became clinically manifest - at least seems intriguing. C. I. EDVARDSMITH LENNARTHAMMARSTROM Department of Clinical Immunology, Huddinge Hospital, and Department of Immunobiology, Wallenberglaborato~y, Karolinska Institute, 104 05 Stockholm, Sweden.
References 1 Gorsuch, A. N., Lister, J., Dean, B. M. et al. (1981) Lancet ii, 1363-1365
M o r e o n rat m o n o c l o n a l antibodies SIR, I perfectly agree with D r Clark and his colleagues that rat hybridomas have advantages over their mouse counterparts (Immunol. Today, 1983, Vol. 4, pp. 100-101), at least in some cases. However, they do not mention the L O U ( L O U for L O U V A I N ) rat model, which is at the basis of this technology. The $210 tumour (the original name of the tumour from which the cell lines 210 R C Y 3Agl and then Y3 Ag 1, 2, 3 were selected by C. Milstein and colleagues) has been characterized as a Bence-Jones producer ~ and adapted to in-vitro culture (quoted in Ref. 1 and described in Ref. 2) and was given to C. Milstein, free of charge, by my colleagues and myself in 1972. The L O U rat model has made the study of rat immunoglobulin easier. It allowed the characterization of the rat IgG2c subclass and two out of the four known rat immunoglobulin allotypes (those of the IgA and IgG2b classes), and it provided the first IgE- and IgDsecreting plasmacytomas in any animal species. It also provided the first rat fusion line (Y3 A g 1,2,3) ~ and, afterwards, the first rat non-secreting fusion line (IR983F) 45 ' which is histocompatible with one rat inbred strain [the Y3 line is a r-secreting cell line and the nonsecreting Y2B is histocompatible only with ( A O x LOU)F1 animals]. It has
2 Asplin, C. M., Cooney, M. K., Crossley, J. R. et al. (1982)J. Pediatr. 101,398-400 3 Doniach, D. and Bottazzo, G. F. (1981) in Clinical Immunology Update (Franklin, E. C., ed.), pp. 95-121, Elsevier, New York 4 Gorsuch, A. N. and Cudworth, A. G. in Paediatric Immunology (Soothhill, J. F., Greenwood, H., Hayword, A. R. and Wood, C. B. S., eds), Blackwell Scientific Publications, Oxford (in press) 5 Smith, C. I. E., Hammarstr6m, L. and Matell, G. Stand. J. Immunol. (in press) (Abstract) 6 Asherson, G. L. and Dumondc, D. C. (1963) Immu~log~ 6, 19-24 7 Raft, M. C. (1971)/sr.J. Med. Sci. 7,724-727 8 Hammarstr6m, L., Smith, C. I. E., Primi, D. and M611er,G. (1976) Nature (London) 263, 60-61 9 Pirskanen, R., Bergstr6m, K., Hammarstr6m, L. et aL (1981)Ann. NYAcad. Sci. 377, 606-613 10 Grob (ed.) (1981) Ann. NYAcad. Sd. 377
already provided m e and my colleagues with hundreds of interesting rat-rat hybridomas 5-a. T h e IR983F cell line is also the first non-patented rat fusion line. Success in making rat-rat hybridomas presently means a rational use of the L O U rat model. A n u m b e r of papers have been published on rat immunoglobulins and on rat polyclonal or monoclonal antibodies by many authors and by ourselves (a list of references from the Experimental Immunology U n i t is available) and these, for example, include data on the rat IgG isotypes which fix h u m a n complement 9'1°. H. BAZIN Experimental Immunology Unit, University of Louvain, 1200 Brussels, Belgium.
References 1 Bazin, H., Deckers, C., Beckers, A. and Hermans, J. F. (1972) Int. J. Cancer 10, 568-580 2 Burtonboy, G., Bazin, H., Deckers, G. et aL (1973) Eur. J. Cancer9, 259-262 3 Galfre, G., Milstein, C. and Wright, B. (1979) Nature(London) 277, 131-133 4 Bazin, H., Grzych, C., Verwaerde, C. and Capron, A. (1980)Ann. Immu.n~l.(Paris) 131D, 359 5 Bazin, H. (1982) Protides Biol. Fluids, Proc. Colloq. 29,615-618 6 Burtonboy, G., Bazin, H. and Delferri~re, N. (1982)Arch. ViroL 71,291-302 7 Crzych, J. M., Capron, M., Bazin, H. and Capron, A. (1982)J. Immunol. 129, 2739-2743 8 Lebacq, A. M. and Bazin, H. Bull. Cancer(in press) 9 Medgyesi, G. A., Ffist, G., Gerfely, J. and Bazin, H. (1978) Immunochemisto, 15, 125-129 10 Ffist, G., Medgyesi, G., Bazin, H. and Gergely, J. (1980) Immunol. Lett. 1,249-253
274 et al., unpublished observations). At the
time of clinical onset of disease, there was a marked increase in the a m o u n t of antiacetylcholine receptor antibodies. T h e production of autoantibodies is certainly not equivalent to having an a u t o i m m u n e disease. Thus, all individuals carry low amounts of different autoantibodies 6'7, possibly due to polyclonal B-lymphocyte activation (including self-reactive cells) primarily by bacterial products 8. Furthermore, increased amounts of autoantibodies directed against islet cells~ and acetylcholine receptor protein 9 have been observed in healthy relatives of patients with insulin-dependent diabetes mellitus and myasthenia gravis, respectively. T h e frequencies of relatives having autoantibodies were far too high to imply that all affected individuals would later develop a clinically overt a u t o i m m u n e disease. Although the role of different autoantibodies is still a matter of debate in a n u m b e r of a u t o i m m u n e disorders, there is strong evidence that immunoglobulins directed against acetylcholine receptor protein have pathogenic importance in myasthenia gravis ~°. T h e above data are thus compatible with the view that at least some of the etiological steps in the a u t o i m m u n e disease process take place several years before the disease becomes clinically manifest. T w o observations argue in favour of an even longer time interval between the initial phase and the overt disease. O n e concerns the finding of anti-islet cell antibodies in individuals later developing insulin-dependent diabetes mellitus. In these individuals the autoantibodies were already present in the first serum sample tested ~'2 and it may well be that they had appeared much earlier. T h e other concerns the cell interactions in the a u t o i m m u n e process. It is our belief that in the majority of autoi m m u n e diseases, the autoantibody production is T-cell dependent. Thus, it is possible that the activation of autoreactive T lymphocytes precedes that of B cells. However, when T- and B-lymphocyte reactivity is studied after immunizations, in the majority of cases they parallel each other, and there is no obvious reason to believe that the kinetics of a u t o i m m u n e reactions would differ. T h e idea that there is a long time inter-
val between the initial etiological steps and the manifest autoimmune disease certainly raises the question W h a t takes place in the interval? However, irrespective of the answer to that question, the mere possibility per se namely, that the autoimmune reaction started several years before the disease became clinically manifest - at least seems intriguing. C. I. EDVARDSMITH LENNARTHAMMARSTROM Department of Clinical Immunology, Huddinge Hospital, and Department of Immunobiology, Wallenberglaborato~y, Karolinska Institute, 104 05 Stockholm, Sweden.
References 1 Gorsuch, A. N., Lister, J., Dean, B. M. et al. (1981) Lancet ii, 1363-1365
M o r e o n rat m o n o c l o n a l antibodies SIR, I perfectly agree with D r Clark and his colleagues that rat hybridomas have advantages over their mouse counterparts (Immunol. Today, 1983, Vol. 4, pp. 100-101), at least in some cases. However, they do not mention the L O U ( L O U for L O U V A I N ) rat model, which is at the basis of this technology. The $210 tumour (the original name of the tumour from which the cell lines 210 R C Y 3Agl and then Y3 Ag 1, 2, 3 were selected by C. Milstein and colleagues) has been characterized as a Bence-Jones producer ~ and adapted to in-vitro culture (quoted in Ref. 1 and described in Ref. 2) and was given to C. Milstein, free of charge, by my colleagues and myself in 1972. The L O U rat model has made the study of rat immunoglobulin easier. It allowed the characterization of the rat IgG2c subclass and two out of the four known rat immunoglobulin allotypes (those of the IgA and IgG2b classes), and it provided the first IgE- and IgDsecreting plasmacytomas in any animal species. It also provided the first rat fusion line (Y3 A g 1,2,3) ~ and, afterwards, the first rat non-secreting fusion line (IR983F) 45 ' which is histocompatible with one rat inbred strain [the Y3 line is a r-secreting cell line and the nonsecreting Y2B is histocompatible only with ( A O x LOU)F1 animals]. It has
2 Asplin, C. M., Cooney, M. K., Crossley, J. R. et al. (1982)J. Pediatr. 101,398-400 3 Doniach, D. and Bottazzo, G. F. (1981) in Clinical Immunology Update (Franklin, E. C., ed.), pp. 95-121, Elsevier, New York 4 Gorsuch, A. N. and Cudworth, A. G. in Paediatric Immunology (Soothhill, J. F., Greenwood, H., Hayword, A. R. and Wood, C. B. S., eds), Blackwell Scientific Publications, Oxford (in press) 5 Smith, C. I. E., Hammarstr6m, L. and Matell, G. Stand. J. Immunol. (in press) (Abstract) 6 Asherson, G. L. and Dumondc, D. C. (1963) Immu~log~ 6, 19-24 7 Raft, M. C. (1971)/sr.J. Med. Sci. 7,724-727 8 Hammarstr6m, L., Smith, C. I. E., Primi, D. and M611er,G. (1976) Nature (London) 263, 60-61 9 Pirskanen, R., Bergstr6m, K., Hammarstr6m, L. et aL (1981)Ann. NYAcad. Sci. 377, 606-613 10 Grob (ed.) (1981) Ann. NYAcad. Sd. 377
already provided m e and my colleagues with hundreds of interesting rat-rat hybridomas 5-a. T h e IR983F cell line is also the first non-patented rat fusion line. Success in making rat-rat hybridomas presently means a rational use of the L O U rat model. A n u m b e r of papers have been published on rat immunoglobulins and on rat polyclonal or monoclonal antibodies by many authors and by ourselves (a list of references from the Experimental Immunology U n i t is available) and these, for example, include data on the rat IgG isotypes which fix h u m a n complement 9'1°. H. BAZIN Experimental Immunology Unit, University of Louvain, 1200 Brussels, Belgium.
References 1 Bazin, H., Deckers, C., Beckers, A. and Hermans, J. F. (1972) Int. J. Cancer 10, 568-580 2 Burtonboy, G., Bazin, H., Deckers, G. et aL (1973) Eur. J. Cancer9, 259-262 3 Galfre, G., Milstein, C. and Wright, B. (1979) Nature(London) 277, 131-133 4 Bazin, H., Grzych, C., Verwaerde, C. and Capron, A. (1980)Ann. Immu.n~l.(Paris) 131D, 359 5 Bazin, H. (1982) Protides Biol. Fluids, Proc. Colloq. 29,615-618 6 Burtonboy, G., Bazin, H. and Delferri~re, N. (1982)Arch. ViroL 71,291-302 7 Crzych, J. M., Capron, M., Bazin, H. and Capron, A. (1982)J. Immunol. 129, 2739-2743 8 Lebacq, A. M. and Bazin, H. Bull. Cancer(in press) 9 Medgyesi, G. A., Ffist, G., Gerfely, J. and Bazin, H. (1978) Immunochemisto, 15, 125-129 10 Ffist, G., Medgyesi, G., Bazin, H. and Gergely, J. (1980) Immunol. Lett. 1,249-253
