A radioimmunoassay for ng quantities of DNA was developed. [125l]lododeoxyuridine-labeled DNA was used as the antigen, and the serum of a lupus erythematosus patient served as the source of antibody. The level of free DNA in the serum of 173 patients with various types of cancer and in 55 healthy individuals was determined by this radioimmunoassay. DNA concentration in the normal controls had a range of 0 to 100 ng/ml with a mean of 13 +/- 3 ng/ml (S.E.). For comparison purposes, the range of 0 to 50 ng/ml was designated as normal, and 93% of controls were found in this range. In the cancer patients, the DNA concentration ranged from zero to mug levels with a mean of 180 +/- 38 ng/ml. Fifty % of the patients values were found in the range of 0 to 50 ng/ml; the other 50% were between 50 and 5000 ng/ml. No correlation could be seen between DNA levels and the size or location of the primary tumor. Significantly higher DNA levels, however, were found in the serum of patients with metastatic disease (mean of 209 +/- 39 ng/ml), as compared to nonmetastatic patients (mean 100 +/- 30, p less than 0.02). After radiation therapy in lymphoma, lung, ovary, uterus, and cervical tumors, the levels decreased in 66 to 90% of the patients, whereas in glioma, breast, colon, and rectal tumors, the DNA levels decreased only in 16 to 33% of the patients. Generally, the decrease in DNA concene of tumor size and reduction of pain. Conversely, when DNA levels either increased or remained unchanged, a lack of response to the treatment was noted. Of 17 patients who died within a year, 13 showed DNA levels that remained high or unchanged, whereas only 4 showed lower levels during treatment. Persistent high or increasing DNA levels in the circulation, therefore, may signal a relapse and are probably a poor prognostic sign. The relatively high percentage (50%) of cancer patients with apparently normal DNA levels would suggest that this test may have low diagnostic value. It should be pointed out, however, that all these patients represent a selected group considered for radiation therapy, usually after surgery and/or chemotherapy. It is possible that a better correlation between DNA levels and cancer will be obtained prior to the initiation of treatment. On the other hand, DNA in the serum may be an important tool for the evaluation of therapy or the comparison of different regimens.

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Free DNA in the Serum of Cancer Patients and the Effect of Therapy

Biologic and clinical significance of cryoglobulins. A report of 86 cases.

Cancer is associated with mutated genes, and analysis of tumour-linked genetic alterations is increasingly used for diagnostic, prognostic and treatment purposes. The genetic profile of solid tumours is currently obtained from surgical or biopsy specimens; however, the latter procedure cannot always be performed routinely owing to its invasive nature. Information acquired from a single biopsy provides a spatially and temporally limited snap-shot of a tumour and might fail to reflect its heterogeneity. Tumour cells release circulating free DNA (cfDNA) into the blood, but the majority of circulating DNA is often not of cancerous origin, and detection of cancer-associated alleles in the blood has long been impossible to achieve. Technological advances have overcome these restrictions, making it possible to identify both genetic and epigenetic aberrations. A liquid biopsy, or blood sample, can provide the genetic landscape of all cancerous lesions (primary and metastases) as well as offering the opportunity to systematically track genomic evolution. This Review will explore how tumour-associated mutations detectable in the blood can be used in the clinic after diagnosis, including the assessment of prognosis, early detection of disease recurrence, and as surrogates for traditional biopsies with the purpose of predicting response to treatments and the development of acquired resistance.

Liquid biopsy: monitoring cancer-genetics in the blood.

Background. Type II cryoglobulinemia is a vasculitis characterized by cryoglobulins consisting of complexes of polyclonal IgG and monoclonal IgM rheumatoid factors, the cause of these immune complexes is unknown, though both the hepatitis B (HBV) and C (HCV) viruses have been suspected. Methods. We studied 19 patients with Type II cryoglobulinemia for markers of HCV and HBV infection. Quantitative HCV antibody and RNA studies were performed on whole serum, cryoprecipitates, and supernatants. Results. Eight patients (42 percent) had HCV antibodies, and 16 (84 percent) had HCV RNA. Of the 19 patients, 5 (26 percent) had HBV markers, but only 1 had evidence of active HBV infection. Control serum samples from nine patients with Type I cryoglobulinemia were negative for HCV antibody and HCV RNA. There was a close, although not exclusive, association of one type of rheumatoid factor (WA) with HCV RNA. HCV antibody and HCV RNA were concentrated approximately 10-fold and 1000-fold, respectively, in the T...

A role for hepatitis C virus infection in type II cryoglobulinemia.

Publisher Summary Autoantibodies to nuclear antigens (ANAs) have assumed an important place in the diagnostic armamentarium of the clinician because of distinct profiles of ANAs in different diseases. Profiles of ANAs have, therefore, been extremely useful in differential diagnosis, where the disease does not have classical or full-blown manifestations.. Immune complexes formed in the circulation or in situ mediate tissue injury by the activation of complement and other inflammatory mediators. Not only do these antibodies precipitate their respective antigens but also other proteins or nuclear RNAs that might be associated with them in special ways. The reasons for these special associations of protein antigens with specific sets of nuclear RNAs is unknown, but the possibility that there might be functional relationships in these complexed particles is not unreasonable. The key question that pervades the minds of many investigators in this field is the reason for the appearance of ANAs in certain individuals. It is highly improbable that the phenomenon is a random immune response to nuclear breakdown products, because the types of ANAs in different diseases are strikingly different. Some known environmental agents are drugs, such as hydralazine and procainamide, that together with lower levels of hepatic acetyltransferase enzyme predispose the host to the development of ANAs. Another agent may be the Epstein–Barr virus that is a ubiquitous environmental agent.

Autoantibodies to nuclear antigens (ANA): their immunobiology and medicine.

The specificities of anti-polynucleotide antibodies found in human sera were studied using several immunological procedures. Anti-native DNA (NDNA) antibodies and certain anti-double-stranded RNA (DSRNA) antibodies were found to react with single-stranded DNA (SDNA), and anti-NDNA antibodies were observed to react more avidly with SDNA than with NDNA in most sera tested. Antibodies to NDNA showed no preferential reactivity with NDNA or SDNA derived from mammalian tissue, bacterial, or viral sources. Precipitating antibodies reactive with individual bases, with common determinants of bases, and with common determinants of SDNA and NDNA were detected utilizing synthetic polydeoxyribonucleotides. Antibodies to DSRNA were also heterogeneous and reactive with both Poly A · Poly U and Poly I · Poly C in addition to reactivity with Poly A and SDNA. In contrast, antibodies to a ribonucleo-protein determined by hemagglutination and by precipitation showed no reaction with NDNA, SDNA, or DSRNA. Serial studies of serum specimens from patients with systemic lupus erythematosus (SLE) indicated that anti-NDNA antibodies were closely associated with disease activity. Titers of antibodies to SDNA or DSRNA were also frequently increased during these periods but in addition showed peaks during quiescent periods. Anti-NDNA antibodies were detected in most patients' sera at sometime during the course of the disease. Three patients were observed with active SLE, who did not develop anti-NDNA antibodies, even in the presence of severe renal disease. Evidence that other antigen-antibody systems may also play a role in the pathogenesis of the renal disease was particularly apparent in these patients. Anti-ribonucleoprotein antibodies were not well correlated with the peaks of antibody activity of other polynucleotide antibodies, suggesting that an independent immunogen was responsible for induction of these antibodies. The close association of certain populations of anti-polynucleotide antibodies during the course of active SLE, the presence of cross-reacting antigenic determinants of SDNA, NDNA, and DSRNA, the preferential avidity of anti-NDNA antibodies for SDNA, and the frequent increase of anti-SDNA antibodies in SLE and other diseases associated with active tissue destruction suggest that SDNA is a ubiquitous antigen that may stimulate the formation of antibodies reactive with a variety of polynucleotides.

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Antibodies to polynucleotides in human sera: antigenic specificity and relation to disease

Serological studies, immunofluorescence studies, and immunochemical assays of glomerular eluates indicate that several antigen-antibody systems may be involved in the pathogenesis of the tissue lesions of SLE. The NDNA-anti-NDNA system appears to be operative in most patients with active SLE. In addition, antibodies to SDNA are found with considerable frequency in SLE sera and glomerular eluates. It is not known if these antibodies fix to NDNA which has been denatured after deposition in glomeruli or if SDNA-anti-DNA complexes are deposited initially. NDNA antigen has been demonstrated in both serum and glomerular deposits, and SDNA determinants have also been found in glomerular deposits. In addition, there is evidence that rheumatoid factor contributes to the immune complex deposition in certain patients either by fixing to preformed immune complexes or as part of an independent gamma-globulin-anti-gamma-globulin system. It is anticipated that the definition of these immune systems, and the assessment of their relative toxicity will provide insight into underlying etiologic factors as well as provide a sound basis for therapy in this form of glomerulonephritis.

Systemic lupus erythematosus: prototype of immune complex nephritis in man

Precipitin reactions of C1q in gel diffusion proved useful in detecting unknown complexes containing γ-globulin in the sera of patients with SLE. Using this method low molecular weight C1q reactants also have been detected in a number of sera from patients with SLE as well as other diseases. Both the circulating complexes and the unidentified low molecular weight reactants are associated with disease activity and in vivo complement depression. In some sera from patients with SLE, circulating complexes as detectable by C1q precipitation were closely associated with cryoprecipitins and an active nephritic process. Evidence is presented that both rheumatoid factors and C1q interact with circulating complexes in these patients and that the interaction is related to cryoprecipitation. The demonstration of the same rheumatoid factors in the cryoprecipitates and in the renal glomerular deposits suggests that rheumatoid factors have a special significance in the presence of circulating complexes.

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C1q PRECIPITINS IN THE SERA OF PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND OTHER HYPOCOMPLEMENTEMIC STATES: CHARACTERIZATION OF HIGH AND LOW MOLECULAR WEIGHT TYPES.

Single-stranded DNA (SDNA) occurs in high incidence and in greatest concentration in the sera of patients with systemic lupus erythematosus (SLE), where levels as high as 250 mug/ml were observed. SDNA appears to be an imunogen for anti-SDNA antibodies and forms complexes in vivo of both anti-SDNA-SDNA and anti-NDNA-SDNA types, which apparently play a role in the pathogenesis of the glomerulonephritis found in patients with SLE, SDNA is also found in high incidence but at lower levels in the sera of patients with rheumatoid arthritis. Lesser amounts of SDNA are found in several other diseases in which a low incidence of anti-SDNA antibodies is observed.

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The occurrence of single-stranded DNA in the serum of patients with systemic lupus erythematosus and other diseases.

Hemagglutination procedures were used to determine the distribution of antibodies to native DNA, single-stranded DNA, and double-stranded RNA. Antibodies to all three polynucleotides were found in a high percentage of the serums of patients with systemic lupus erythematosus. Antibodies to native DNA occurred almost exclusively in serums of patients in the active stages of systemic lupus erythematosus, whereas antibodies to single-stranded DNA were observed in the serums of patients with several diseases and of some normal individuals.

https://science.sciencemag.org/content/sci/166/3913/1648.full.pdf

V. Agnello

Papers

Antibodies to polynucleotides in human sera: antigenic specificity and relation to disease

Systemic lupus erythematosus: prototype of immune complex nephritis in man

C1q PRECIPITINS IN THE SERA OF PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS AND OTHER HYPOCOMPLEMENTEMIC STATES: CHARACTERIZATION OF HIGH AND LOW MOLECULAR WEIGHT TYPES.

The occurrence of single-stranded DNA in the serum of patients with systemic lupus erythematosus and other diseases.

Antibodies to polynucleotides: distribution in human serums.