Ernest Witebsky

Hereditary Autoimmune Thyroiditis in the Fowl

In the Cornell C strain of White Leghorn chickens, thyroiditis appeared spontaneously. It was characterized by phenotypic changes due to a decrease of thyroxine, histological damage to the thyroid gland, and the presence in the seruim of antibodies to thyroglobulin. Susceptibility to the disease is genetically inherited. Hormonal bursectomy (androgen given to the embryo) suppresses the development of thyroiditis.

Studies on experimental thyroiditis.

The increasing attention directed to the role of autoimmunity in the pathogenesis of various diseases requires tha t efforts be intensified to elucidate the biological mechanisms underlying the phenomenon. For this purpose, studies of human disease are profitably coupled with investigations using experimental animals, where the immunological and pathological consequences of autosensitization can be observed under controlled conditions. Because of its resemblance to human chronic thyroiditis, experimental thyroiditis represents a particularly significant model. This autoimmune disease can be produced in several animal species including the rabbit, guinea pig, dog, rat, and mouse by injection of autologous, homologous or even heterologous thyroid protein, usually with Freund adjuvant. I t is characterized by formation of circulating autoantibodies and of delayed hypersensitivity to thyroglobulin, and by development of inflammatory changes in the animals own thyroid gland. Major problems exist in our understanding of the induction of this disease, its transfer from one animal to another, and the mechanisms actually responsible for cellular damage. The purpose of this paper is to survey briefly some current investigations underway in our laboratory on these topics.

Potent Typing Sera Produced by Treatment of Donors with Isolated Blood Group Specific Substances.

Conclusions The intravenous treatment of donors with purified A and B specific substances isolated from animal sources leads to a considerable increase in isoantibody titer. The substances used were highly purified and did not contain any demonstrable hog or horse protein. The administration of even small amounts is effective and results in the production of sera which are characterized by high titer, speed and specificity. The procedure described easily permits the production of large quantities of very potent typing serum.

Localization of Thyroid and Spinal Cord Autoantibodies by Fluorescent Antibody Technic

Summary (1) Sections of normal spinal cords of rabbits were treated with rabbit antisera produced by immunization of rabbits with rabbit spinal cord suspensions; the treated sections were stained with fluorescein conjugated goat antiserum to rabbit immune globulin. Selected areas stained suggest the myelin sheath as at least one of the antibody combining sites, though further histological studies are needed. No staining was obtained with normal sera or with rabbit sera containing thyroid autoantibodies. (2) In the same manner sections of thyroid glands of normal rabbits were exposed to the action of rabbit sera containing rabbit thyroid autoantibodies and stained with fluorescein conjugated goat antiserum to rabbit immune globulin. Positive staining reactions were obtained in the colloid extending into adjoining epithelial layer. Interstitial tissue remained basically unstained. No positive staining reactions were obtained using normal rabbit serum or rabbit serum containing brain autoantibodies. (3) With thyroid autoantibodies, the positive staining reactions and antibody titers seemed to run roughly parallel. However, rabbit autoantisera failed to give staining reactions when diluted above ninefold. On the basis of limited experience with spinal cord autoantisera, it is not possible to make a statement regarding appearance of positive staining reactions and presence of demonstrable circulating antibodies, though the data obtained are suggestive of a correlation.

Demonstration of Rh antibody in breast milk.

Conclusion The occurrence of an Rh antibody in the breast milk of a woman with an erythroblastotic child is described. The patients serum, too, contained a very potent antibody against Rh blood cells.

Serologic Studies of Rabbit Antibodies to Rabbit Submaxillary Glands.

Summary Sera of rabbits immunized with pooled rabbit submaxillary gland suspensions were studied by complement fixation and tanned cell hemagglutination technics. 1. Some of these antisera (3 out of 7) fixed complement in presence of rabbit submaxillary gland extracts. 2. Complement fixing activity of 2 of the 3 sera studied in detail was specific for submaxillary gland extracts within the limits of antigens tested. One of 3 serologically active sera (#1565) cross reacted with parotid gland extracts. 3. The globulin fraction of submaxillary gland extracts contained virtually all the material in the extract which was reactive with rabbit submaxillary gland antibodies. Some activity was also found in the microsome fraction. 4. Extracts of the submaxillary glands of the antibody-producing animals themselves reacted just as strongly as those of other rabbits, indicating the autoantibody nature of the antibodies elicited by isoimmunization. 5. Most of the rabbit antisera (6 out of 7) agglutinated tanned red cells coated with rabbit submaxillary globulin. 6. By hemagglutination inhibition tests, one antiserum (#1565) was found to be inhibited by submaxillary and parotid extracts. The other antisera tested were specific for submaxillary gland antigens. These results agree with those obtained by complement fixation.

THE THYROID GLAND AS SOURCE AND TARGET IN AUTOSENSITIZATION

The proteins of the thyroid gland have been studied for several reasons. In addition to their attractiveness to endocrinologists and biochemists, they possess unusually high interest for immunologists. These antigens were first studied because they exhibited in an unambiguous fashion the phenomenon of organ specificity.*pz For example, if extracts of various hog organs are tested with rabbit antiserum elicited by thyroid extract, it is found with many of these antisera that thyroid extract gives a positive result at a much greater dilution than do other organ preparation^.^ More recently, the thyroid has acquired even greater interest with the discovery of its role in thyroiditis, and its capability of actually eliciting autountibodies. From experimental studies of animals it was established that circulating antibodies could be demonstrated by several techniques after suitable injection of thyroid extract from within the species or even from the same animal.4 This condition was frequently accompanied or followed by extensive degenerative changes in the thyroid tissuechanges that, in fact, resembled human thyroiditis.6 Subsequent studies on a large number of human sera revealed a very high degree of correlation between the occurrence of thyroid antibodies in people with chronic nonspecific thyroiditis and its absence in other conditions or in normal serum.6,7 To learn more about the character of this autosensitization response and the nature of the autoantibody, we have again immunized a group of rabbits and followed the serum changes with time. We present some of the results in this report. At the same time it has also seemed to be of importance to learn more about the antigen or antigens involved, and for this and other reasons we have been studying newer methods of purification, using hog thyroid extract as test material. Some of these results are also presented.

Experimental autoallergic orchitis in rhesus monkeys.

Summary Rhesus monkeys were injected with monkey testicular extract incorporated into Freund adjuvant. All six monkeys developed a histological picture of orchitis. The testicular lesions consisted of congestion and serous edema, with sloughing of germinal cells from the tubules; these cells appeared to fill the epididymis ducts. Lesions were more pronounced between 10 and 13 weeks after immunization. Lymphocytic infiltration was present in moderate intensity in only one animal. Circulating antibodies were detected in a few animals at very low titer; however, following castration the titers increased. The organ specificity of the antibody response could be well documented by means of immunofluorescence. According to the results obtained, auto- as well as isosensitization of rhesus monkeys with monkey testicular material incorporated into complete Freund adjuvant produces histological and serological changes very similar to those seen in human experimental orchitis.

Thyroid-Specific Autoantibodies Studied by Passive Cutaneous Anaphylaxis of Guinea Pig

Summary 1. Passive cutaneous anaphylaxis of the guinea pig has been successfully used to study thyroid autoantibodies of rabbit, guinea pig, and man. 2. The thyroid autoantibody proved to be specific for the homologous antigen (thyroid extract and purified derivative) and did not give cross reactions with thyroid extracts of other species. 3. Five human sera with high titer of thyroid autoantibody were studied. The antibody was completely neutralized by human thyroid extract or human thyroglobulin, but was not significantly affected by any of a variety of other organ extracts or of iodinated amino acids, again indicating the specificity of this type of antibody.

Virological investigations of chickens with spontaneous autoimmune thyroiditis. I. Isolation and transmission studies.

The autoimmune nature of spontaneous chronic thyroiditis in the Obese Strain (OS) of White Leghorn chickens has been reported previously (2). Additional documentation of these findings has included studies on the nature of the antibodies (8), the spontaneous development of the disease (3), and the consequences of bursectomy (6) and thymectomy (7). The potential usefulness of this model in studies of autoimmune processes has been emphasized. An important aspect of the problem concerns the possible role that a virus may play in the pathogenesis of this disease. In the studies reported in this and a following paper (9), no evidence was obtained of viral infection in spontaneous autoimmune thyroiditis. Four strains of chickens were used. The OS chickens were derived from the Cornell C-strain during 1955-1958 (1) and bred as a closed flock for more than eight generations (The historical data on the OS and C-strains were supplied by Dr. R. K. Cole, Cornell