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The "LipoGen RheumaStrip ANA Profile" test method (LipoGen, Inc.) is a new assay format for autoantibody detection in which recombinant autoantigens are used. This enzyme immunoassay, in test-strip format, detects antibodies to autoantigens U1-ribonucleoprotein (U1-RNP), Sm, SS-A/Ro, SS-B/La, and to native DNA (nDNA). We evaluated 200 antinuclear antibody (ANA)-positive and 100 ANA-negative sera for the presence of antibodies to U1-RNP, Sm, SS-A/Ro, SS-B/La, and nDNA by the new test-strip procedure. These data correlated well with those obtained with either Ouchterlony double immunodiffusion for U1-RNP, Sm, SS-A/Ro, and SS-B/La or with Crithidia luciliae indirect immunofluorescence for anti-nDNA. Assay sensitivity and assay specificity of the ANA Profile method as compared with those of established procedures were respectively as follows: 89.8% and 98.8% for U1-RNP, 86.4% and 95.3% for Sm, 97.9% and 89.3% for SS-A/Ro, 98.3% and 86.3% for SS-B/La, and 97.5% and 93.1% for nDNA. Agreement between the ANA Profile test and these other test methodologies ranged from 88.7% for the SS-B/La test to 97.3% for the U1-RNP test. This new test procedure substantially decreases the time and effort required to perform these assays. Total hands-on time and overall assay time were decreased by 72% and 97%, respectively.

University of California, Davis line 200 White Leghorn chickens develop an inherited progressive fibrotic disease that includes the appearance of antinuclear antibodies (ANA). To further characterize these ANA, serial aged line 200 birds were studied. Greater than 50% of line 200 birds develop antinuclear and anticytoplasmic antibodies; fluorescent staining patterns included cytoplasmic spider web, most prevalent at 1 mo of age, and fine speckled patterns, characteristic of chickens 6 mo and older. By enzyme-linked immunosorbent assay, 40.4% of line 200 birds were found to have antibodies to single-stranded DNA (ssDNA). In contrast, antibodies to histones, RNA, or poly A . poly U were not detected. Precipitating antibodies to saline extracts from chicken liver were noted in 33.3% of line 200 birds. Saline extracts from turkey, pheasant, and partridge liver but not rat, rabbit, or mouse tissues were also positive in immunodiffusion testing with these line 200 birds. The antigenicity of chicken liver extracts was sensitive to pronase, protease K. and pH variations greater than 10 and less than 5; however, they were resistant to trypsin. DNase. RNase, and incubation at 37 degrees C and 56 degrees C for 1 h. Cell fractionation in conjunction with column chromatographic techniques revealed that several protein antigens with apparent molecular weights in the range of 62,000-290,000 were present in cytoplasm but not in isolated nuclei. Line 200 sera were not reactive against nuclear ribonucleoprotein, Sm, Scl-70, or SS-B/La antigens. Thus, line 200 chickens develop antinuclear and anticytoplasmic antibodies at an early age, which recognize a unique group of protein antigenic determinants found only in avian species. Moreover, and of particular interest, the presence of autoantibodies to saline-extractable antigens correlated with positive ANA, antibodies in ssDNA, and to the clinical expression of disease.

Adult nonpregnant female rhesus monkeys fed purified diets containing 100 or 4 ppm zinc for 1 yr were mated then studied through midgestation. At mating, zinc-deprived (ZD) monkeys showed maternal lymphocyte response to mitogens concanavalin A (Con A) and phytohemagglutinin (PHA), serum uric acid and carbon dioxide, and WBC lower than in control (C) monkeys. There was a significant positive association between plasma zinc and PHA response. At midgestation, discriminant analysis revealed that maternal lymphocyte response to Con A, fetal abdominal circumference (by ultrasound), plasma fibrinogen, serum IgM, and amniotic fluid iron level were discriminators for diet group, all lower in ZD than in C monkeys. Maternal plasma and RBC zinc at midgestation were positively associated with fetal growth and plasma uric acid. These observations suggest that immune function (ie, mitogen response and serum immunoglobulin level) is a strong discriminator of dietary zinc deprivation in rhesus monkeys, both before and during pregnancy.

To assess long-term effects of marginal zinc deprivation on pregnancy, adult non-pregnant female rhesus monkeys were fed diets containing 100 or 4 ppm zinc for 1 yr. then mated; effects on pregnancy and its outcome are under study. During this year, food intake was not depressed in zinc-deprived (ZD) monkeys, and there were relatively few effects on biochemical or hematological indices. By the end of the year, plasma zinc concentration was somewhat lower in ZD monkeys than in controls. Several immune variables, including serum IgM and IgG levels and polymorphonuclear leukocyte (PMN) function, were depressed in the ZD group, changes closely reflecting circannual fluctuations in plasma zinc levels in both diet groups. Endotoxin-activated plasma from ZD monkeys had less potential to promote chemotaxis than that from control monkeys, suggesting that defective PMN function may relate to a plasma effect. Marginal zinc deprivation may thus influence immune function before other variables are affected.

Progressive systemic (sclerosis) is one of the most enigmatic of the rheumatic diseases. It is a connective tissue disorder of unknown etiology characterized by fibrosis in skin and internal organs. Although similar lesions are found with increased prevalence in workers exposed to coal, gold, silica, and polyvinyl chloride, most patients have had no known predisposing factors. Select reports of a familial occurrence of PSS have been observed but a definitive genetic basis is lacking and no clear associations with the major histocompatability complex have been demonstrated. Moreover, although a variety of immunologic abnormalities in patients with PSS have been reported, they are generally diffuse and non-diagnostic. Such abnormalities include defects in cell mediated immunity, increases in sera immunoglobulins, antinuclear antibodies, and cryoglobulins. In contrast to these non-specific findings, there appears to be significant evidence of a relationship between cell mediated immunity to collagen and appearance of scleroderma. For example, peripheral blood lymphocytes in patients with scleroderma undergo lymphocyte transformation when cultured with specific collagen preparations. The pathology of skin and internal organs in PSS generally reflects both collagen deposition and small vessel occlusion. All organ systems may be involved but mortality significantly increases with involvement of heart, kidney, or lung. Unfortunately, at present a reliable experimental model of PSS has not been found although similar immunopathology can be induced in homologous disease of rats and in chronic graft vs host disease of humans.

Serologic and correlational testing was performed in a series of 65 patients diagnosed as having juvenile arthritis (JA) and in 21 age matched controls to detect the presence of antinuclear antibodies (ANA), antibodies to ssDNA, IgM and IgG rheumatoid factor (RF), immune complexes (IC) and antibodies to bovine type I and human type II collagen. ANA were found in 51% of the JA patients; the highest incidence (75%) was noted in the pauciarticular onset disease group. Low levels of anti-ssDNA antibodies were detected in 22% of the patients, all of whom had active disease. IgM RF was detected in 35% of the JA patients but only 6% of patients had IgG RF. Similarly, about one fourth of the JA patients had IC detected by the Clq assay. Antibodies to bovine type I and human type II collagen were noted in about 12% of the JA patients.