Antibodies to nucleic acids in juvenile-onset diabetes

Antibodies to single stranded (SS-) and double stranded (DS-) DNA and RNA were determined by a passive microhemagglutination assay in sera from 80 children with juvenile-onset diabetes mellitus (JDM) and 129 children with asthma. The latter group was chosen for comparison with the JDM group because of their increased susceptibility to viral infection and the nonautoimmune nature of the disease. We found that JDM patients had increased titers of antibodies to SS-DNA (61.3%), synthetic polyadenylicpolyuridylic acid (Poly A-U) (78.8%), synthetic polyinosinicpolycytidylic acid (Poly I-C) (62.5%), and DS-RNA of statolon virus (51.3%) and reovirus (27.3%), respectively, in contrast to asthmatics (15.5, 34.9, 3.9, 20.2, and 2.3%, respectively) or to healthy controls. The difference of the incidence of antibodies among the groups is statistically significant (P less than 0.001). Presence of SS-DNA antibody found in two thirds of cases of JDM further support the increased prevalence of autoimmune phenomenon in that disease. Furthermore, the increased prevalence of DS-RNA antibodies in patients with JDM, found especially in cases of recent onset, is suggestive of an active immune response against the underlying viral replications that may have led to beta cell injury in islets of pancreas.

Assessment of cellular and humoral immunity of myasthenics

A close association of autoimmune diseases or autoimmune phenomena in myasthenia gravis is well known. A comprehensive immunological study of 22 patients with myasthenia gravis showed that changes in the immune system mainly involve the thymus-derived lymphocytes (T cells). Anti-thymus antibody was present in 90% of the patients, and it paralleled the frequency of thymic abnormality in myasthenia gravis. It is postulated that in myasthenia gravis the altered T cell functions caused by anti-thymus antibody result in the formation of an array of autoantibodies including the factor which blocks the neuromuscular transmission.

Defective phagocyte adherence in acute poststreptococcal glomerulonephritis: clinical and laboratory observations

The adherence of circulating phagocytes to glass was studied in 15 children with acute poststreptococcal glomerulonephritis and in 27 healthy adults, 21 healthy children, and 14 children with normocomplementemic renal disease. The phagocytic adherence to glass in the patients with hypocomplementemic PSGN differed significantly from that of the control groups (p=less than 0.001). There was a positive correlation of phagocyte adherence with plasma C3 but not with plasma C4, C3, properdin factor B, severity of illness, or drugs administered. In addition, the adherence defect was present in two normocomplementemic PSGN patients. The defect gradually resolved in all patients with clinical improvement: it was useful as an index of recovery. The in vitro addition of functional C3 to whole blood produced the adherence defect in normal subjects and failed to correct the defect in patients with PSGN. It was postulated that a fragment of activated complement may have blocked a membrane receptor on these phagocytes and interfered with their adherence to glass.

Insulin-dependent diabetes: a disease of autoaggression

Lymphocytes from patients with insulin-dependent diabetes demonstrated significant cytoadherence and cytotoxicity against human insulinoma cells in vitro as compared to lymphocytes from normals. Complement was not involved in insulinoma cell destruction. The findings suggest that insulin-dependent diabetes may be a disease of autoaggression.

Synthesis of secretory component by human colon cancer cells

Colon carcinoma, established in long-term tissue culture, has been shown to synthesize secretory component (SC). These molecules can be demonstrated both on the cell surface and in the cytoplasm by immunofluorescence. Regeneration of SC was demonstrable after trypsinization of the cells. In culture, two lines of carcinoma epithelium were shown to incorporate (14C) leucine into newly synthesized SC. These cell lines should provide useful preparations for studying the details of immunoglobulin-SC interactions.

Morula forms of E rosettes: distribution, specific inhibition, and enhancement

Rosetts-forming cells (RFC) with more than 10 sheep red blood cells (SRBC's) per cell defined as morula-forming cells (MFC) were studied in human lymphoid organs and in the peripheral blood (PBL). MFC are most common in the thymus (more than 50%) and the frequency is much less in peripheral lymphoid tissues and in the blood (29.8% in those less than 5 years old; 14.9% in adults). There is very slight decrease in total RFC in PBL over age 5, but the changes in MFC are quite striking. Treatment with antihuman thymus antiserum (ATS) and with anti-human lymphoblastic antiserum (ATL) resulted in significant inhibition of total rosette and morula rosette formation. No inhibition was seen using normal brain antiserum, anti-IgM antiserum, or anti-L chain antiserum. In two patients with chronic lymphocytic leukemia and in some cases of thymic deficiency the ratio of MFC to total RFC was unusually high. After culture with phytohemagglutinin (PHA) and conversion to blast forms or after surface peturbation by papain or freeze-thaw treatment, MFC numbers were increased.

Antibody to cultured human insulinoma cells in insulin-dependent diabetes

Circulating antibodies to live tissue-cultured human-insulinoma cells were identified in 34 out of 39 insulin-dependent diabetic patients by an indirect immunofluorescent technique. The antibodies were unrelated to insulin therapy since 8 of 9 sera obtained before insulin-replacement treatment were antibody positive and the test results were not influenced by prior addition of porcine insulin to sera. The antibodies were of the IgM and IgG classes. The findings suggest that autoimmune mechanisms are important in the pathogenesis of most cases of insulin-requiring diabetes.

Beta 2-microglobulin: association with lymphocyte receptors

beta(2)-Microglobulin (beta(2)m) is a low-molecular-weight protein constituent of lymphocyte membranes. Amino acid sequence analysis has revealed a high degree of homology between the beta(2)m and certain regions of immunoglobulin molecules, suggesting a possible recognition function for the beta(2)m, in analogy with the immunoglobulins. The data presented demonstrate that highly specific antiserum against beta(2)m blocks lymphocyte reactivity against allogeneic cells in mixed leukcocyte cultures and against phytohemagglutinin, both of which processes presumably function via a cell surface receptor on thymus-derived (T) lymphocytes. There is very little inhibition of T lymphocyte rosette formation with sheep red blood cells. The findings suggest a possible relation between the beta(2)m and recognition units on the T lymphocyte surface.

Antibody-associated lymphotoxin in acute infection

Five pediatric patients who were known to be previously healthy acutely developed lymphopenia during various viral or mycoplasma infections. In one case, fatal generalized varicella occurred and in another, severe toxic epidermal necrolysis ensued. To further investigate this phenomenon, a study was done to determine the incidence of and elucidate the pathogenesis of lymphopenia occurring during the acute phase of viral or mycoplasma infections. Acute and convalescent sera from patients with viral or mycoplasma infection and children immunized with live measles virus were screened for lymphocytotoxic activity against normal lymphocytes by the microcytotoxicity method of Terasaki and McClelland (1). Sera with lymphocytotoxic activity were found in 15 of 48 cases of viral infections, 4 of 22 mycoplasma infections, and 1 of 11 measles virus immunized persons. All those who had sera which were cytotoxic to lymphocytes in vitro had lymphopenia. The lymphocytotoxic activity resided in 19S fractions in 8 of 11 positive sera while the remaining 3 had activity both in 19S and 7S fractions and could be completely removed by absorption with antilight chain antiserum. The cytotoxic activities were all complement-dependent and were greater at 37 degrees C than at 4 degrees C. The significance of acute acquired immunologic deficiency due to the development of antibody-associated lymphotoxin (AbAL) during acute infections is discussed and five cases having more severe clinical manifestations are presented (Appendix).

Trisomy 18 syndrome in Chinese infants. Clinical findings and incidence

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Trisomy 13 syndrome in Chinese infants. Clinical findings and incidence

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