Compartmentalisation between gut and lung mucosae in a model of secondary immunodeficiency: effect of thymomodulin.

UNLABELLED: Compartmentalisation of mucosal immune response seems to be the result mainly of the preferential migration of activated cells back to their inductive sites. The aim of this report was to demonstrate, in a model of secondary immunodeficiency in Wistar rats (severely protein deprived at weaning and refed with casein 20%; group R21), that the oral administration of Thymomodulin (group:R21TmB) has different effects on gut and BALT (Bronchus-associated lymphoid tissue). Tissue sections (5 mu) were studied by immunohistochemistry 1). The oral administration of Thymomodulin restores only in gut Lamina propria (LP) the IgA B and CD4 T cell populations to control levels. The CD8a and CD25 subpopulations do not vary in gut as they return to control levels when refed with 20% casein diet. All the populations mentioned above remained decreased even after receiving Thymomodulin by the oral route. However, the same behaviour was observed for the TCR delta T cells that were decreased and return to normal levels in both mucosae by the effect of the immunomodulator; 2) when studying the iIEL (intestinal intraepithelial lymphocytes) CD8 alpha, CD25 and TCR gamma delta T cells, that were increased in R21, return to control levels in R21TmB. In BALT intraepithelium CD8 alpha and CD25 T cells remained decreased, while only TCR gamma delta T cells (increased in R21) return to control values. CONCLUSIONS: 1) there exists a compartmentalisation between both mucosae, as T CD4+ and IgA B+ cells are restored by TmB only in gut; 2) only those iIEL involved in inflammation (CD8 alpha+/CD25+ and TCR gamma delta+/CD25+) are normalised by means of the Thymomodulin 3) however, in BALT,only TCR gamma delta+ T cells are restored 4) the oral administration of the present immunomodulator may be useful as a therapeutic agent, although the preferential survival in the tissue of initial stimulation is the major factor in the preferential distribution of activated cells.

Effect of RN-301 immunomodulator on bronchus-associated lymphoid tissue (BALT) in protein depleted rats at weaning.

It has been previously demonstrated in Wistar rats that severe protein deprivation at weaning, even after refeeding with a 20% casein diet for 21 days, provokes alterations in IgA+ B cell and T cell populations from gut and GALT (gut associated lymphoid tissue) that are reverted by immunomodulator IM-104. In the present report, we investigate the influence of RN-301 (quite similar to IM-104) given by the oral or subcutaneous route during the protein deprivation period, in the seeding of BALT with IgA+ B and CD5+ T cells. The immunomodulator RN-301 contains LPS from E. coli and membrane and ribosomal fractions of P. acne. Tissue sections of the lower respiratory tract were studied by immunohistochemistry. The immunomodulator RN-301 administered by the oral route favours the significant increase in the seeding of the BALT lamina propria with IgA+ B and CD5+ T cells (p < 0.001). However, the RN-301 given by the subcutaneous route does not favour the repopulation of the BALT lamina propria. The ribosomal fractions from P. acne associated with LPS from E. coli contained in the immunomodulator RN-301 administered by the oral route may rescue the small resting lymphocytes in the gut-associated lymphoid tissue (GALT). This event favours their proliferation and migration to the BALT.

Thyroid function and antibody studies in pernicious anaemia.

Thyroid antibodies were demonstrated in 57% of thirty pernicious anaemia patients without overt thyroid disease. Elevated basal thyroid stimulating hormone (TSH) levels and an enhaced TSH response to thyrotrophin releasing hormone (TRH) only occurred in thyroid antibody positive subjects; by contrast the thyroid antibody negative subjects in the older age group frequently and undetecable basal TSH levels and an impaired TRH response. Thyroid hormone concentrations provided no absolute evidence of hypothyroidism in any of the patients.

Classification of smooth muscle autoantibodies detected by immunofluorescence.

Three hundred and twelve sera containing antibodies to smooth muscle (SMA) wer analysed for the immunofluorescence patterns they produced in various tissues. A classification is described based on the three main appearances in rat kidney. Some sera, mainly of low titre, reacted only with vessel walls (SMA-V), some stained vessels and renal glomeruli (SMA-G) and high titre sera, mainly from patients with chronic active hepatitis stained vessels, glomeruli, and intracellular fibrils in renal tubules (SMA-T). Peripheral staining in hepatocytes or thyroid cells was not a regular feature. 41/43 polyclonal SMA-T and -G sera were absorbed out completely by actin, and this also removed the pericullular staining in liver and thyroid when present. High titre SMA-V antibodies could not be absorbed by actin, and the antigen remains to be identified.

Autoantibodies to prolactin-secreting cells of human pituitary.

A new autoantibody which reacted with anterior-pituitary tissue was deteected by immunofluorescent staining. Of 287 patients having one or more autoimmune endocrine diseases, sera from 19 reacted with pituitary glands obtained at hypophysectomy for breast cancer. Using specific rabbit antibodies to each of the six pituitary hormones and rhodamine-labelled goat-anti-rabbit-immunoglobulin (Ig) followed on the same unfixed cryostat section by a patients's serum counterstained with fluorescein-conjugated sheep-anti-human-Ig, it was posssible to show that the autoantibodies reacted specifically with the hypertrophied prolactin cells in these glands. The antibodies, belonging to the 3 main Ig classes, were complement fixing, with titres varying from 1 to 80. Double staining of prolactin cells and analogy with other autoimmune systems suggested that the antigen is in cytoplasmic organelles involved in the synthesis or delivery of the hormone. No pituitary antibodies were found in panhypopituitary cases, but there are indications that antibodies to other pituitary cells exist in some sera and that an autoimmune process may account for some cases of isolated pituitary hormone defects occurring in adult life.

Paraproteins with antibody activity in acute viral hepatitis and chronic autoimmune liver diseases.

Of 27 patients with liver disease and cryoglobulinaemia 18 proved to have paraproteins. Six of these monoclonal immunoglobulins were shown to have antibody activity, directed to human gamma globulin, alpha(1)-fetoprotein, smooth muscle, and mitochondria.Eight of the patients suffered from acute viral hepatitis, five of whom were HB Ag positive; in all these cases the monoclonal spikes were transient and their antibody activities were directed against IgG in two cases and alpha(1)-fetoprotein in one.Seven of the patients had active chronic hepatitis and in these the paraproteinaemia persisted, though remaining quantitatively unchanged over several years. One of them had a cryoprecipitable monoclonal smooth muscle antibody. Three patients had primary biliary cirrhosis and in two of them monoclonal IgM mitochondrial antibodies were demonstrated.In three out of the 18 cases there was a double M-component.Since these monoclonal antibodies are directed to autoantigens not unlike the polyclonal ones usually seen in autoimmune hepatic diseases, it is suggested that the factor which triggers the uncontrolled plasma cell proliferation to produce paraproteins must meet cells from an already expanding clone.