A solid-phase enzyme immunoassay for the common and subtypic determinants of hepatitis B surface antigen with monoclonal antibodies

Monoclonal antibodies were raised against the common (a) as well as subtypic determinants (d, y, w and r) of hepatitis B surface antigen (HBsAg). They were applied to subtyping HBsAg by sandwiching it between antibody against a fixed on a solid-phase support and antibody against one or other of d, y, w and r, linked to horseradish peroxidase. The assay was applied to evaluate antigenic specificities of the NIH and Japanese panels composed of 44 sera containing HBsAg particles of various subtypes. HBsAg particles of a hybrid subtype, adyr, were sandwiched between monoclonal antibody against d and that against y, thereby indicating that they possessed both d and y determinants on the selfsame particle. The expression of d and y determinants on hybrid HBsAg particles was much less than that on ordinary particles of adw, adr, ayw or ayr subtype.

A radioimmunoassay that sandwiches human interleukin-2 between radiolabeled monoclonal antibody and the receptor on a hematopoietic cell line

Two monoclonal antibodies were raised against human interleukin-2 (IL-2) produced by E. coli harboring recombinant complemental DNA. Both antibodies did not neutralize its activity, nor did they inhibit the binding of IL-2 to the receptor on target cells. Taking advantage of the ability of monoclonal antibodies to detect IL-2 that had bound to the receptor, a radioimmunoassay was developed that sandwiched IL-2 between the radiolabeled monoclonal antibody and the receptor on a hematopoietic cell line infected with human T cell leukemia virus Type I. The assay had the advantage of detecting only IL-2 with the ability to bind to the receptor, and displayed a linear dose-response relationship over concentrations ranging from 5 to 100 ng/ml.

Large hepatitis B surface antigen polypeptides of Dane particles with the receptor for polymerized human serum albumin

Large hepatitis B surface antigen polypeptides with apparent molecular sizes of 39,000 and 43,000 daltons (P39 and P43) were liberated from a purified preparation of Dane particles of subtype adr. They were tested for reactivity with monoclonal antibodies raised against three synthetic oligopeptides representing fundamental sequences of the pre-S region in deoxyribonucleic acid of hepatitis B virus (subtype adr), as well as with monoclonal antibody against the major surface antigen polypeptide (P22) coded for by the S gene. Both P39 and its glycosylated form P43 bound to all four monoclonal antibodies, thereby indicating that they were coded for by the sequence of 1200 nucleotides, from the second ATG codon in the pre-S region to the stop codon of the S gene. Both P39 and P43 bound to polymerized human and chimpanzee albumins, but not to polymerized albumin from species without susceptibility to hepatitis B virus. Due to their presence in Dane particles and the expression of a polyalbumin receptor, the immune responses against P39 and P43 may have significance in infection with hepatitis B virus and its immunoprophylaxis.

Selective absence of immunoglobulin A1 or A2 among blood donors and hospital patients

A hemagglutination inhibition assay was developed for the determination of immunoglobulin A1 and A2 (IgA1 and IgA2) with subclass-specific rabbit antiserums. Among 93,020 apparently healthy blood donors, selective absence of IgA1 was found in six and that of IgA2 in 15, at a prevalence much higher than the absence of total IgA that was revealed by only one donor. Among 6800 hospital patients with various disorders, the absence of IgA1 was found in one with breast cancer and that of IgA2 in two with rheumatoid arthritis.

Correlative expression of C3b receptors in the glomerulus and on erythrocytes

The reactivity of glomerular C3b receptors (CR1) measured by the number of sheep erythrocytes bearing C3b (EAC) that adhered to glomeruli in frozen sections, was compared with the reactivity of erythrocyte CR1, which was determined by immune adherence hemagglutination (IAHA), in 22 patients with renal and non-renal diseases. Among seven patients with primary glomerulonephritis whose erythrocytes were positive for IAHA, the reactivity of glomerular CR1 was high in five. In the remaining two, the reactivity of glomerular CR1 was low, accompanied by severe sclerotic glomerular changes. Erythrocytes from five of six patients with systemic lupus erythematosus were IAHA negative, and their glomeruli failed to produce adherence of EAC, even in three cases in which there were no detectable C3 deposits or histopathological changes. In the other nine patients without appreciable glomerular changes, the reactivity of glomerular CR1 was low in three along with negative erythrocyte IAHA, whereas the remaining six exhibited high CR1 reactivity both in glomeruli and on erythrocytes. The results indicate a close correlation between the expression of CR1 in the glomerulus and on erythrocytes.

Immunoglobulin A antibody against hepatitis B core antigen in the acute and persistent infection with hepatitis B virus

Antibody to hepatitis B core antigen of immunoglobulin A class was determined in the serum of patients infected with hepatitis B virus by a sandwich-type solid-phase radioimmunoassay with monoclonal antibodies. The antibody, as defined by a sample to normal ratio greater than 2.1, was detected in all of 39 patients with acute hepatitis, with titers varying widely depending on the time of blood sampling. In persons with persistent infection, the antibody was detected in only 2 (4%) of 46 asymptomatic carriers of the virus, contrasting with the positivity in as many as 15 (41%) of 37 patients with chronic persistent hepatitis, in 45 (94%) of 48 patients with chronic active hepatitis, and in 40 (87%) of 46 patients with liver cirrhosis with or without hepatocellular carcinoma. The mean +/- SE titer of antibody in chronic persistent hepatitis (3.8 +/- 0.9) was significantly lower than those in chronic active hepatitis (13.8 +/- 3.2) and cirrhosis with or without carcinoma (25.6 +/- 6.1) (p less than 0.001). Based on the results obtained, the antibody may reflect hepatic injury in the persistent hepatitis B virus infection.

Characterization of pathogenic constituents of Cryptococcus neoformans strains

We examined seven strains, comprising five serotypes, of Cryptococcus neoformans to determine what constituents of the organisms are responsible for pathogenicity and virulence in BALB/c mice. C. neoformans strains were divided into three virulence classes by survival rates after intravenous inoculation of 1 X 10(5) or 1 X 10(7) viable cells, and virulence was found not to be correlated with serotype or capsular size. C. neoformans cells resisted phagocytosis in different degrees in the presence of normal serum. Sensitivity of the C. neoformans strains to singlet oxygen ranged from resistance to susceptibility. Histological examination revealed that a weakly encapsulated virulent strain induced inflammatory responses with granuloma formation in the liver, lung, and kidney in addition to formation of cystic foci in the brain. In contrast, although the heavily encapsulated virulent strain produced granulomatous lesions in the liver, this strain preferably produced mucinous cystic foci in the lung, kidney, and brain. Correlation between virulence, and biological, histopathological and physiological evidence suggests that C. neoformans strains are endowed with the implicated multiple pathogenic constituents in various degrees and proportions. The following are suggested as the most important pathogenic constituents: a polysaccharide capsule responsible for resistance to phagocytosis and formation of cystic foci; a cell surface structure for responsible for resistance to intra- or extracellular killing and induction of the granulomatous lesion; a growth rate suitable for interacting with phagocytic elimination.

Mercuric reductase enzymes from Streptomyces species and group B Streptococcus

Mercury volatilization (Hg2+ reductase) activity has been found with Hg2+-resistant isolates of three Streptomyces species and with three Hg2+-resistant strains of group B Streptococcus from clinical sources in Japan. Hg2+ reductase activities in crude cell extracts showed the temperature sensitivity, the requirement for an added thiol compound and the characteristic dependence on NAD(P)H cofactors of similar enzymes isolated from other bacteria.

A two-site sandwich radioimmunoassay of human gamma interferon with monoclonal antibodies

Two monoclonal antibodies (nos. 6008 and 6016) were raised against human gamma interferon (IFN-gamma) derived from E. coli harboring the recombinant cDNA for IFN-gamma, and one (3710) against a synthetic peptide representing its C-terminus amino acid sequence of 20 residues. The monoclonal antibody against the synthetic peptide (3710) reacted either with IFN-gamma or the synthetic peptide. One monoclonal anti-IFN-gamma (6008) did not react with the synthetic peptide, while the other (6016) showed a weak binding with the peptide. The binding of the monoclonal antibody against the synthetic peptide (3710) with IFN-gamma was not inhibited by 6008, but to a certain extent by 6016. A 2-site '1-step' radioimmunoassay was developed in which 6008 was fixed on a solid-phase support, and the test sample together with radiolabeled 3710 was added for the binding with it. The assay was rapid with a sensitivity capable of detecting a few ng/ml of IFN-gamma.

Electrophoretic patterns of extracellular deoxyribonuclease (DNase) and their correlation with T-type in group A streptococci

Molecular heterogeneity of the extracellular deoxyribonuclease (DNase) in group A streptococci was demonstrated in 42 clinical isolates. Although polyacrylamide gel electrophoretic patterns of the extracellular DNase of all the isolates were heterogeneous, they could be divided into five main patterns with respect to the presence or absence of three DNase components including DNase B. By comparing the electrophoretic patterns of DNase in all the isolates with their T-types, we found that the patterns were quite characteristic for their T-types, especially in the prevalent T-types 12 and 1, and that the isolates of T-types 12 and 1 produced DNase B as their major extracellular DNase. Relative DNase B activity in the total extracellular DNase activity of group A, B, and G isolates was determined by the rapid method of neutralization with anti-DNase B antibody. The results showed neutralization of DNase activity in all the isolates of group A streptococci, largely corresponding to their T-types, but not of the isolates of groups B and G. These results indicate that the electrophoretic patterns of the extracellular DNase of group A streptococci are closely correlated with their T-types, suggesting the physicochemical taxonomic value of these properties.

Hemagglutination assay of polypeptide coded by the pre-S region of hepatitis B virus DNA with monoclonal antibody: correlation of pre-S polypeptide with the receptor for polymerized human serum albumin in serums containing hepatitis B antigens

The receptor for polymerized human as well as chimpanzee serum albumins has been identified on the 55-amino acid polypeptide coded by the pre-S region of hepatitis B virus DNA. Monoclonal antibodies were raised against a synthetic polypeptide of 19 amino acid residues representing a hydrophilic region of the pre-S amino acid sequence deduced from hepatitis B virus DNA. Sheep erythrocytes fixed with glutaraldehyde were coated with monoclonal antibody against the synthetic polypeptide to develop a hemagglutination assay for pre-S polypeptide. The pre-S polypeptide was detected in the serum containing hepatitis B surface antigen particles along with hepatitis B e antigen, with titers in parallel with those of the receptor for polymerized human serum albumin.

Hemagglutination assay of polypeptide coded by the pre-S region of hepatitis B virus DNA with monoclonal antibody: correlation of pre-S polypeptide with the receptor for polymerized human serum albumin in serums containing hepatitis B antigens

The receptor for polymerized human as well as chimpanzee serum albumins has been identified on the 55-amino acid polypeptide coded by the pre-S region of hepatitis B virus DNA. Monoclonal antibodies were raised against a synthetic polypeptide of 19 amino acid residues representing a hydrophilic region of the pre-S amino acid sequence deduced from hepatitis B virus DNA. Sheep erythrocytes fixed with glutaraldehyde were coated with monoclonal antibody against the synthetic polypeptide to develop a hemagglutination assay for pre-S polypeptide. The pre-S polypeptide was detected in the serum containing hepatitis B surface antigen particles along with hepatitis B e antigen, with titers in parallel with those of the receptor for polymerized human serum albumin.

Low capacity of erythrocytes to bind with immune complexes via C3b receptor in patients with systemic lupus erythematosus: correlation with pathological proteinuria

Erythrocytes from 51 patients with systemic lupus erythematosus and 75 controls were tested for the capacity to bind aggregated human gamma-globulin labeled with radioiodine in the presence of complement. Both in patients and controls, a trimodal distribution of binding capacity was observed. Low (less than 9% of the added radioactivity), intermediate (9-17%), and high binding (more than 17%) were observed in 13, 58, and 29% in controls and in 49, 43 and 8% in lupus patients. The low binding capacity of erythrocytes persisted even after patients entered remission following steroid therapy. A genetic control of binding capacity was supported by familial surveys. Prevalence of pathological proteinuria was significantly higher in patients with low binding capacity than those with intermediate or high binding capacity (16/25 vs 7/26, P less than 0.01). These results indicate that an impaired physiological disposal of immune complexes via the erythrocyte C3b receptor in lupus patients may contribute to the development of renal involvement.

Factors influencing postexposure immunoprophylaxis of hepatitis B virus infection with hepatitis B immune globulin. High deoxyribonucleic acid polymerase activity in the inocula of unsuccessful cases

Hepatitis B immune globulin was given intramuscularly to 102 staff members of a dialysis unit within 48 h after the accidental needlestick exposure to blood containing hepatitis B surface antigen (HBsAg). Hepatitis B virus (HBV) infection developed in 11 of 56 persons (20%) who had been exposed to blood containing hepatitis B e antigen (HBeAg). Among 56 HBeAg-positive inocula, HBsAg-associated deoxyribonucleic acid polymerase activity in the 11 inocula that transmitted HBV infection was significantly higher than that in the remaining 45 inocula that did not (log counts per minute 3.27 +/- 0.57 vs. 2.09 +/- 1.19, p less than 0.001). These 11 HBeAg-positive inocula revealed higher hemagglutination titers of HBsAg (geometric mean 13.5 +/- 1.4 vs. 11.2 +/- 3.2, p less than 0.001). The receptor for polymerized human serum albumin was detected significantly more often in the inocula that transmitted HBV infection than those that did not (10/11 vs. 24/45, p less than 0.05). Based on the results obtained, the failure in protecting all of those exposed to HBeAg-positive blood would be attributable to a high concentration of HBV in some HBeAg-positive inocula and the inability of intramuscular injection to raise a protective level of antibody in the circulation immediately.

A two-site sandwich radioimmunoassay of beta 2-microglobulin with monoclonal antibodies

Among 21 batches of monoclonal antibodies raised against beta 2-microglobulin (anti-beta 2m), 6 reacted with soluble beta 2m, as well as with beta 2m present in association with HLA heavy chains on the surface of leukocytes. The remaining 15 anti-beta 2m antibodies bound with soluble beta 2m, but failed to react with beta 2m on the cell surface. No monoclonal anti-beta 2m antibodies revealed precipitin lines when they were tested against beta 2m in immunodiffusion. When 2 anti-beta 2m antibodies with different specificities were mixed together, however, they developed a precipitin line against beta 2m. Based on these observations, there was only 1 epitope on beta 2m that was available for the binding with a monoclonal anti-beta 2m antibody with either specificity. This allowed the development of a solid-phase radioimmunoassay in which beta 2m in test specimens was sandwiched between immobilized anti-beta 2m of 1 specificity and radiolabeled anti-beta 2m of a heterologous specificity in a single step. Monoclonal antibodies with at least 2 different specificities would be required for developing a sandwich-type immunoassay of polypeptides, such as beta 2m, that do not display 2 or more epitopes of the same specificity.

Low C3b receptor reactivity on erythrocytes from patients with systemic lupus erythematosus detected by immune adherence hemagglutination and radioimmunoassays with monoclonal antibody

C3b receptor (CR1) on erythrocytes from 23 patients with systemic lupus erythematosus (SLE) and 124 normal controls was determined by immune adherence hemagglutination (IAHA) and radioimmunoassay. The binding of radiolabeled monoclonal anti-CR1 to erythrocytes and their lysate was distributed continuously in a wide range. The majority of SLE patients showed low binding by both assays. CR1 sites on erythrocytes were determined also by Scatchard plot analysis and standardized by the number of similarly determined lectin-binding sites that served as a measure of erythrocyte surface. The numbers of standardized CR1 sites were classified as high, intermediate, and low. Thirty-six percent of control subjects had high numbers of CR1 sites, 53% had intermediate numbers, and 11% had low numbers. Of SLE patients, the numbers of CR1 sites were high in 0%, medium in 52%, and low in 48%. Negative IAHA was found in 10 controls (8%), all of whom had low numbers of standardized CR1 sites. Among 13 SLE patients with negative IAHA, 11 had low numbers of CR1 sites and the remaining 2 had low intermediate numbers. IAHA, therefore, was particularly efficient in detecting the low numbers of CR1 sites in SLE, which would impair the disposal of circulating immune complexes and accelerate the development of tissue injuries.

Comparative study of streptococcal DNase by rapid and quantitative assay systems

Clinical isolates of group A, B, and G streptococci were compared in regard to their extracellular deoxyribonuclease (DNase) activities by the modified assay system for DNase using DNA-methyl green complex as a substrate. DNase activity in a culture supernatant of each strain was measured as a percent decrease in the substrate-specific absorbance at 640 nm. After 1 hr incubation, DNase activities in all the strains of group A streptococci were found to be markedly higher than those of any strain in the other groups, although the DNase activities in groups B and G were considerably heterogeneous. These findings were also seen when commercially available DNA-dye complex reagent for the determination of anti-DNase B antibody titer was used as a substrate in the assay system. Our results suggest that this newly established assay system could be applicable for the rapid measurement of DNase activity to distinguish group A streptococci from the other groups.

Deposition of hepatitis B e antigen in membranous glomerulonephritis: identification by F(ab')2 fragments of monoclonal antibody

The pathogenic ability of hepatitis B e antigen (HBeAg) to induce membranous glomerulonephritis was evaluated by the most specific method presently available. Monoclonal antibody was raised against HBeAg, and F(ab')2 fragments were obtained and labeled with fluorescence. By this reagent, 10 out of 16 patients with membranous glomerulonephritis with hepatitis B surface antigen in the serum revealed granular deposition of HBeAg along glomerular capillary walls. Among the cases with glomerular HBeAg deposits, nine had detectable HBeAg in the serum and one had antibody to HBeAg (anti-HBe). The specificity of HBeAg staining was ascertained by blocking and inhibition tests, and the fluoresceinated anti-HBe F(ab')2 reagent did not stain the glomerular immune deposits in the patients with membranous glomerulonephritis who did not carry hepatitis B virus (HBV). None of the studied patients showed deposition of hepatitis B surface or core antigens in the glomerulus. On the basis of these results, immune complexes involving HBeAg may induce membranous glomerulonephritis in persons who carry HBV.

Low molecular weight (7s) immunoglobulin M antibody against hepatitis B core antigen in the serum for differentiating acute from persistent hepatitis B virus infection

Sera from persons infected with hepatitis B virus were fractionated into 19s and 7s moieties by high performance liquid chromatography and then tested for the antibody to hepatitis B core antigen (anti-HBc) of immunoglobulin M (IgM) class by radioimmunoassay. Sera from 17 patients with acute or fulminant hepatitis invariably showed a high activity of 19s IgM anti-HBc (sample/normal ratio 30.6 +/- 13.6). In addition, they all revealed a much lower activity of 7s IgM anti-HBc (4.1 +/- 3.4). In remarkable contrast, 7s IgM anti-HBc activity was higher than 19s IgM anti-HBc activity in the sera from 5 asymptomatic carriers (10.4 +/- 2.4 vs. 1.0 +/- 0.1), 4 patients with chronic persistent hepatitis (11.7 +/- 1.4 vs. 2.1 +/- 1.4), 13 with chronic active hepatitis (13.6 +/- 3.0 vs. 6.0 +/- 5.6), and 10 with liver cirrhosis (8.9 +/- 3.4 vs. 5.4 +/- 2.4). Among these 32 cases of persistent hepatitis B virus infection, there were only 2 (6.3%) in which the 7s IgM anti-HBc was lower than the 19s IgM anti-HBc. The proportion of patients who showed the value of 7s IgM anti-HBc exceeding that of 19s IgM anti-HBc was significantly higher for persistent (30 of 32) than for acute (0 of 17) hepatitis B virus infection (p less than 0.001). On the basis of these results, the determination of IgM anti-HBc in terms of 19s and 7s subpopulations would be useful for differentiating acute from chronic hepatitis B virus infection, especially when the titer of IgM anti-HBc is not high enough to exclude a persistent hepatitis B virus infection.

Three-dimensional morphological study of rat gastric lesions induced by N-methyl-N'-nitro-N-nitrosoguanidine. Structural atypia in carcinoma and non-carcinomatous lesions

Lesions of the rat glandular stomach induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) were classified into 4 categories: intramucosal lesions; polypous lesion; downward-growth lesions, and unequivocal adenocarcinomas. Each lesion was examined by three-dimensional reconstruction from serial sections to study the spacial arrangement of the glandular tubules. In the intramucosal lesions, the tubules showed tree-like branchings. In the polypous lesions and downward-growth lesions, the tubules were interconnected to form a three-dimensional network. In unequivocal adenocarcinomas, the tubules appeared separated and were dispersed into nests. These findings indicate that interruption of continuity of the epithelium in proliferated tubules is a possible sign of malignant transformation. Erosions were always observed in the intramucosal, the polypous and the downward-growth lesions. There were locations in the tubular system where the tubules became so attenuated as to resemble cord like structures. Inflammatory reactions were always demonstrable in the intertubular spaces in such lesions. These findings indicate that MNNG-induced anatomical changes may participate in the formation of erosions by causing local obstruction of the ductules.

Beta-propiolactone for the inactivation of non-A/non-B type 1 hepatitis virus capable of inducing cytoplasmic tubular ultrastructures in chimpanzees

Non-A/Non-B type 1 hepatitis virus may be recognized because it induces characteristic tubular ultrastructures in the hepatocyte cytoplasm of chimpanzees. 3 chimps received 0.1 ml of a chimp serum containing more than 100 chimp infecting units of non-A/non-B type 1 hepatitis virus after it had been treated with beta-propiolactone with or without combined ultraviolet irradiation. All of the chimps escaped infection throughout the observation period of 23 weeks. The treatment of the serum with beta-propiolactone at the mildest condition employed (0.05%, 4 degrees C, 20 min) was still effective in inactivating the virus. The susceptibility of the chimps was ascertained by the subsequent challenge with 0.1 ml of the untreated serum which invariably induced non-A/non-B type 1 hepatitis in them. On the basis of these results, beta-propiolactone was extremely efficacious for the cold sterilization of non-A/non-B type 1 hepatitis virus.

A two-site sandwich radioimmunoassay of human fibroblast (beta-) interferon with monoclonal antibodies

Monoclonal antibodies were produced against human fibroblast (beta-)interferon (IFN-beta). Four of them were directed to the determinant designated a, while the remaining 3 to another determinant named b. An IFN molecule was found to bear one each of a and b determinants arranged in such a manner that the occupation of a with the corresponding antibody did not interfere with the binding of b to its corresponding antibody, and vice versa. This allowed the development of a 2-site sandwich radioimmunoassay in which antibody to b was immobilized on wells of a microtiter plate and the bound antigen was detected by the radiolabeled antibody to a. The 2-site sandwich radioimmunoassay detected, with a high sensitivity, IFN-beta either induced from fibroblast or produced by Escherichia coli harboring the gene of IFN-beta.

Long-term in vivo carcinogenicity test of fish meal pyrolysate in Syrian golden hamsters

The carcinogenicity of fish meal pyrolysate was examined in noninbred Syrian golden hamsters of both sexes. Hamsters were given a diet containing 5%, 10%, 20% or 40% fish meal pyrolysate for 102 weeks in Experiment 1, and 10% or 20% fish meal pyrolysate for 112 weeks in Experiment 2. Hamsters in control groups in both experiments were fed a normal basal diet. Various tumors were found in both experimental and corresponding control groups, but there was no significant difference in the incidence of any tumors between the experimental and control groups. Thus, the fish meal pyrolysate tested was not carcinogenic to Syrian golden hamsters under these conditions. In male hamsters the severity and incidence of fatty degeneration of the liver and chronic nephropathy tended to correlate with the concentration of fish meal pyrolysate in the diet. With females, however, the correlation was not so clear. In neither sex did the presence of atrial thrombosis or systemic amyloidosis appear to be dependent on the dietary concentration of fish meal pyrolysate.

A hepatitis B surface antigen polypeptide (P31) with the receptor for polymerized human as well as chimpanzee albumins

Hepatitis B virus, and hepatitis B surface antigen particles co-occurring with hepatitis B e antigen, have the receptor for polymerized human and chimpanzee albumins that may be involved in the hepatotropism of hepatitis B virus. We identified the receptor on a hepatitis B surface antigen polypeptide with a molecular size of 31,000 daltons (P31). P31 bound to polymerized albumins from human and chimpanzee, but did not react with polymerized albumins from the experimental animals without susceptibility to hepatitis B virus. P31 was composed of the major polypeptide of hepatitis B surface antigen with a molecular size of approximately 22,000 daltons (P22) and additional 55 amino acid residues coded by the pre-S region in the hepatitis B virus-specific deoxyribonucleic acid. Because P22 did not react with polymerized albumin, the sequence of 55 amino acid residues in the pre-S region appeared to bear the receptor. Polypeptides with the receptor for polymerized albumin may make an efficacious hepatitis B vaccine, because they could raise antibodies against the putative site on hepatitis B virus capable of binding with hepatocytes to initiate the infection.

Immunochemical structure of hepatitis B e antigen in the serum

Hepatitis B e antigen (HBeAg) constitutes the nucleocapsid of hepatitis B virus (HBV) and occurs in association with plasma proteins, particularly with IgG, in the serum of persons infected with the virus. A polypeptide with an approximate m.w. of 15,500 (P15.5) is obtained either from HBeAg in the serum or from the nucleocapsid of HBV. P15.5 preparations from serum and virus resembled closely each other in the amino acid composition. The C-terminus amino acid sequence of P15.5 from serum was determined to be -Thr-Thr-Val-Val, whereas that from the virus ended with -Thr-Thr. The same sequence of four amino acid residues was found on the gene coding for the nucleopeptide of hepatitis B virus with a molecular size of 19,000 daltons (P19). P15.5 identified on the nucleotide sequence of P19 was composed of 149 amino acid residues with a calculated molecular size of 16,770 daltons. The gene coding for P19 had two -Asp-Pro-connections. By splitting these connections in P19 and P15.5 preparations with formic acid, smaller polypeptides were obtained with sizes predicted from the nucleotide sequence and with the N-terminus amino acid of proline as expected. One of two monoclonal antibodies raised against the core of Dane particles (HBcAg) bound with P15.5 preparations purified from serum and HBV. The IgG fraction from a human serum containing antibodies to HBcAg but not to HBeAg bound with P15.5 also. On the basis of the results obtained, the IgG molecules associated with P15.5 in the serum of persons infected with HBV may well represent the antibodies against HBcAg with limited specificities.

Immunochemical structure of hepatitis B e antigen in the serum

Hepatitis B e antigen (HBeAg) constitutes the nucleocapsid of hepatitis B virus (HBV) and occurs in association with plasma proteins, particularly with IgG, in the serum of persons infected with the virus. A polypeptide with an approximate m.w. of 15,500 (P15.5) is obtained either from HBeAg in the serum or from the nucleocapsid of HBV. P15.5 preparations from serum and virus resembled closely each other in the amino acid composition. The C-terminus amino acid sequence of P15.5 from serum was determined to be -Thr-Thr-Val-Val, whereas that from the virus ended with -Thr-Thr. The same sequence of four amino acid residues was found on the gene coding for the nucleopeptide of hepatitis B virus with a molecular size of 19,000 daltons (P19). P15.5 identified on the nucleotide sequence of P19 was composed of 149 amino acid residues with a calculated molecular size of 16,770 daltons. The gene coding for P19 had two -Asp-Pro-connections. By splitting these connections in P19 and P15.5 preparations with formic acid, smaller polypeptides were obtained with sizes predicted from the nucleotide sequence and with the N-terminus amino acid of proline as expected. One of two monoclonal antibodies raised against the core of Dane particles (HBcAg) bound with P15.5 preparations purified from serum and HBV. The IgG fraction from a human serum containing antibodies to HBcAg but not to HBeAg bound with P15.5 also. On the basis of the results obtained, the IgG molecules associated with P15.5 in the serum of persons infected with HBV may well represent the antibodies against HBcAg with limited specificities.

Three-site sandwich radioimmunoassay with monoclonal antibodies for a sensitive determination of human alpha-fetoprotein

Utilizing monoclonal antibodies against human alpha-fetoprotein, 3 distinct antigenic determinants were identified. These antigenic determinants, provisionally designated a, b and c, were arranged in such a manner that the binding of one determinant with the corresponding antibody did not inhibit, or only barely inhibited the binding of antibodies directed to the other 2 determinants. Monoclonal antibodies with 3 different specificities were, therefore, applied to develop a sandwich-type solid-phase radioimmunoassay of the antigen in which wells were coated with anti-a, and radiolabeled anti-b together with radiolabeled anti-c was employed to detect the bound antigen. The 3-site sandwich radioimmunoassay involving 3 different determinants gave a higher sensitivity than 2-site assays in which only anti-b or anti-c was employed as a radiolabeled reagent, because the radioactivity of the 2 labeled antibodies was added on the antigen bound to immobilized anti-a.

Immunoglobulin M antibody against hepatitis B core antigen for the diagnosis of fulminant type B hepatitis

We attempted to diagnose fulminant type B hepatitis by the hepatitis B core antibody of the immunoglobulin M class. Of 27 consecutive cases of fulminant hepatitis not due to drug-related causes or type A hepatitis, 11 cases with and 9 without hepatitis B surface antigen in the serum revealed a high activity of immunoglobulin M hepatitis B core antibody by radioimmunoassay (S/N ratio 36.3 +/- 20.3). The remaining 7 cases with presumed non-A, non-B hepatitis, as well as the other 4 cases with drug-related causes, did not show any detectable activity (0.99 +/- 0.16). Serums from 30 asymptomatic carriers did not reveal a high activity of immunoglobulin M hepatitis B core antibody (2.1 +/- 1.2), although titers of non-class-specific hepatitis B core antibody were invariably high. On the basis of the results obtained, immunoglobulin M hepatitis B core antibody may be applied for the diagnosis of type B etiology in cases of fulminant hepatitis with or without hepatitis B surface antigen in the serum.

A pitfall in two-site sandwich 'one-step' immunoassay with monoclonal antibodies for the determination of human alpha-fetoprotein

Utilizing monoclonal antibodies directed to 2 distinct antigenic determinants of the human alpha-fetoprotein (AFP), Uotila, Ruoslahti and Engvall developed the 2-site sandwich immunoassay. They found that due to the different specificities of monoclonal antibodies, 2 antigen-antibody reactions, AFP with immobilized antibody and AFP with labeled antibody, could be accomplished in a single step. We have found, however, that above a certain concentration, AFP detectable by their method decreased because the labeled antibody tended to bind with AFP that failed to react with the immobilized antibody. Consequently, 2 different AFP concentrations produced the same result, and an extremely high, still clinically expectable concentration gave a false negative result. Such an inhibition in high AFP concentrations was not observed in the conventional '2-step' immunoassay within the range of concentrations tested (0.1 ng-3 mg/ml). On the basis of these observations, the 2-site '1-step' immunoassay for AFP would have to be applied on multiple dilutions of the serum to avoid an erroneous interpretation of the results.

Entrapment of anti-DNA antibodies in the kidney of patients with systemic lupus erythematosus

Antibodies to single-stranded DNA (anti-ssDNA) and double-stranded DNA (anti-dsDNA) were determined in serum and urine of nine patients with systemic lupus erythematosus (SLE) presenting with heavy proteinuria (greater than 300 mg/dl), and the activity of anti-DNA antibodies was compared between paired serum and urine samples in each patient. The results were expressed by the anti-DNA activity (radioimmunoassay units per milliliter) divided by the concentration of IgG (milligrams per milliliter), so as to correct for the difference of IgG concentration. Anti-DNA was detected invariably in the serum of these patients (anti-ssDNA/IgG 4.8 to 27.2, anti-dsDNA 5.6 to 107.8). In contrast, anti-DNA activity was not detectable in urine samples from any of the nine patients. The urine samples from these patients, as well as those from normal individuals, were found to contain ssDNA at levels not significantly different from each other (0.25 +/- 0.15 vs. 0.19 +/- 0.07 microgram/mg creatinine, P greater than 0.1). The failure to detect anti-DNA in the urine of SLE patients, however, was not due to the ssDNA contained in the urine, because no anti-DNA activity was detected even after their urine samples had been digested with deoxyribonuclease. On the basis of these results, anti-DNA in the serum of SLE patients was considered to be entrapped in the kidney, probably owing to its binding with DNA deposited in their glomeruli.

Demonstration of two distinct antigenic determinants on human alpha-foetoprotein by monoclonal antibodies

Mice were immunized with a purified preparation of human alpha-foetoprotein (AFP) and their spleen cells were hybridized with mouse myeloma cells. Eleven hybridoma cell lines secreting antibody to AFP were obtained. These antibodies were classified into two groups on the basis of different antigenic determinants they recognized. Seven cell lines produced antibodies directed to one determinant of AFP (determinant a), while the remaining 4 produced antibodies to another determinant (determinant b). A native AFP molecule bore one each of a and b determinants which were accessible by monoclonal antibodies; it was detected by a sandwich-type solid-phase radioimmunoassay only when antibody to a was used for coating wells of the microtitre plate and antibody to b as radiolabelled reagent, or vice versa. The presence of two different antigenic determinants on AFP was further confirmed by a chemical modification. When AFP was reduced in the presence of 2 mM dithiothreitol and then alkylated, determinant b was completely destroyed, but the determinant a remained unaffected. Furthermore, reduced and alkylated AFP was detected by the radioimmunoassay employing antibody to a both for coating wells and as radiolabelled reagent, thereby indicating that it bore two determinant as, one of which had been unaccessible in the native AFP.

An extensive primary myocardial fibrosis in progressive systemic sclerosis--a case report with autopsy findings

An extensive myocardial fibrosis due to progressive systemic sclerosis (PSS) was described in a 36-year-old normotensive woman without pulmonary hypertension. An electrocardiogram showed low voltage and a pseudo-infarctional pattern in leads V1 through V3. Right ventricular dilatation and generalized left ventricular hypokinesis were present, but her pulmonary artery pressure was normal. Serum creatine kinase (CK) was elevated to 2305 U/L and CK-MB isoenzyme was as high as 7.1%. Simultaneously performed isoenzyme analysis of CK from the homogenate of the skeletal muscle of the patient showed a similar pattern, thus confirming that serum CK originated mainly from the skeletal muscle lesions. Autopsy findings demonstrated diffuse myocardial fibrosis and relatively unremarkable changes in the lungs and the kidneys. Our case serves as a warning that primary myocardial fibrosis could be, in some cases, so extensive that it might lead to a rapidly aggravated myocardial dysfunction and eventual death.

Membranous glomerulonephritis associated with eosinophilic lymphfolliculosis of the skin (Kimura's disease): report of a case and review of the literature

A 48-year-old male, who had been suffering from eosinophilic lymphfolliculosis of the skin (Kimura's disease) for six years, developed the nephrotic syndrome. Renal biopsy revealed immunopathological and electron microscopic changes characteristic of membranous glomerulonephritis. A review of the literature disclosed a high frequency of renal involvement in Kimura's disease. Out of 175 reported cases of the disease, 21 (12%) were found to have proteinuria including 13 who had the nephrotic syndrome. Some of the patients were noticed to have proteinuria before the onset of the skin lesions, suggesting the existence of common etiological factor(s) capable of inducing both skin and kidney lesions.

Combined passive and active immunization for preventing perinatal transmission of hepatitis B virus carrier state

Prevention of perinatal transmission of hepatitis B virus carrier state in neonates at high risk was attempted by a combined passive and active immunization. Immediately after delivery, ten babies born to mothers who were asymptomatic carriers of hepatitis B surface antigen (HBsAg) and seropositive for hepatitis B e antigen received an intravenous injection of F(ab')2 fragments (200 IU) derived from hepatitis B immune globulin (HBIG). On the following day, none of them revealed detectable levels of the antibody to HBsAg in their sera, and received an intramuscular injection of HBIG (200 IU) which was repeated at 2 and 4 months of age. Vaccination with 40 micrograms of purified, formalin-inactivated HBsAg particles was given to the nine babies at three months and repeated at 4, 5, and 7 months after birth. All of them maintained detectable levels of the antibody and escaped infection throughout the first 12 months of their lives. The one baby who did not have detectable F(ab')2 in serum for 24 hours developed persistent HBs antigenemia which was noticed as early as seven days after birth.

A glycopeptide containing 15 amino acid residues derived from hepatitis B surface antigen particles: demonstration of immunogenicity to raise anti-HBs in mice

The major polypeptides composing hepatitis B surface antigen (HBsAg) particles are P-I and P-II. P-II shares the same amino acid sequence as P-I and contains an additional carbohydrate moiety of mol. wt approximately 5000. When a purified preparation of P-II was digested with Nagarse and then with Pronase P, it gave rise to a glycopeptide containing 15 amino acid residues and the carbohydrate moiety of P-II. The N-terminal amino acid sequence of the glycopeptide was determined to be Lys-Pro-Thr-Asp-Gly-Asn-. The polysaccharide moiety contained 5 moles of N-acetylglucosamine and was connected with Asn at the sixth position from the N-terminus. When mice were immunized against this HBsAg glycopeptide, they raised humoral antibodies which bound to each of three preparations of P-I derived from HGsAg particles of subtypes adw, adr and ayw, thereby indicating that the sequence of 15 amino acids in the glycopeptide would constitute a common antigenic structure of HBsAg.

High titre of antibody to hepatitis B core antigen detected by immune adherence haemagglutination in HBsAg-positive acute hepatitis

Nine patients with HBsAg-positive acute hepatitis were tested for antibody to hepatitis B core antigen (anti-HBc) by the immune adherence haemagglutination method. A high anti-HBc titre (2(15) or more) was found in three, while anti-HBc was not detectable in the remaining six. All of them recovered from hepatitis with the return of hepatic function tests to normal, but HBsAg persisted in the three patients whose acute-phase serum had revealed high anti-HBc titres. On the basis of these observations, the three patients were thought to be persistent HBsAg carriers who had contracted opportunistic acute hepatitis of non-B aetiology. Titration of anti-HBc may be indicated in patients with HBsAg-positive acute hepatitis, because it helps distinguish persistent HBsAg carriers with non-B hepatitis from patients with hepatitis B at the outset, during the episode of acute hepatitis.

Maternofetal transmission of IgG-bound hepatitis B e antigen

Utilizing a highly sensitive radioimmunoassay, hepatitis B e antigen (HBeAg) was detected in the cord serum of eight out of nine babies born to mothers who carried hepatitis B surface antigen together with HBeAg. The titer of HBeAg in the cord serum was much lower than that in the corresponding maternal serum, and escaped the detection by the conventional micro-Ouchterlony immunodiffusion. HBeAg in maternal and cord sera was fractionated into free and IgG-bound moieties by salt precipitation, and their proportion was compared in four pairs. In every pair tested, both free and IgG-bound HBeAg were found in the maternal serum, but only IgG-bound HBeAg was detected in the corresponding cord serum. Based on these results, IgG-bound HBeAg can be transmitted through the placenta, but free HBeAg may barely pass the placenta despite its much smaller size.

Non-A, non-B (type 1) hepatitis agent capable of inducing tubular ultrastructures in the hepatocyte cytoplasm of chimpanzees: inactivation by formalin and heat

We have reported two kinds of viruslike particles derived from human sera that induced morphologically and serologically different types of non-A, non-B hepatitis in chimpanzees. A chimp serum containing one such agent capable of inducing a type of hepatitis with cytoplasmic tubular ultrastructures (non-A, non-B, type 1) was titrated for its infectivity in chimps. Two chimps who received 1 ml of a 10(-2) dilution of the original serum developed the characteristic morphological changes in the liver together with elevated serum transaminase levels, while the other two who received 1 ml of a 10(-4) dilution failed to show such changes. The two who escaped the infection were proven to be susceptible to the agent, because they developed non-A, non-B, type 1 hepatitis when they were challenged by 1 ml of a 10(-1) dilution of the same serum on the 23rd week after the first inoculation. One milliliter of a 10(-1) dilution containing more than 10 chimp infecting units were inactivated in the presence of 1/2000 formalin or by heating at 100 degrees C for 5 min and then given to four other chimps. None of them developed clinical or histologic evidence of non-A, non-B, type 1 hepatitis, thereby indicating that both formalin and heat could destroy the ability of the agent to induce this type of hepatitis.

Timed action of the gene products required for septum formation in the cell cycle of Bacillus subtilis

Four isogenic strains of temperature-sensitive septationless mutants, whose mutations are located on different genes, were used to study the periods of action of the gene products required for the initiation of septum formation during the cell cycle of Bacillus subtilis. The shift-up experiments, in which portions of a synchronous culture of each mutant were transferred to the nonpermissive temperature, showed that the transition point, at which cells attained the ability to divide at the nonpermissive temperature in the cell cycle, was strain specific. Furthermore, the heat shock experiments, in which portions of a synchronous culture were subjected to the nonpermissive temperature before the transition point for a fixed period and shifted back to the permissive temperature, showed that the time interval between the shift-back and the subsequent cell division was specific to each strain but was independent of the age of heat shock. These results led us to the idea that the initiation of septum formation in B. subtilis requires the timed action of the four gene products, each of which functions at a specific stage in the cell cycle. In addition, the result with DNA elongation mutant MK-526, which is also septation defective, supported our previous findings that the initiation of septum formation requires the termination of DNA replication in the previous cell cycle.

Determination of the antibody to hepatitis B e antigen by the inhibition on electrophoresis of free e antigen

A new method is described for the rapid and sensitive detection of the antibody to hepatitis B e antigen (anti-HBe) in serum. Twenty-five microliters of the test serum were incubated with 10 microliter of the purified small 'free' e antigen, and then the consumption of the added antigen was detected by the failure to precipitate with standard anti-HBe in counter-electrophoresis. When a total of 444 serums from asymptomatic carriers of hepatitis B surface antigen was tested for anti-HBe by this method, 348 (78.4%) were found to be positive with a detectability much higher than that of the passive hemagglutination method which detected the antibody in only 264 (59.5%) of the same serums.

Demonstration of two distinct antigenic determinants on hepatitis B e antigen by monoclonal antibodies

Mice were immunized against hepatitis B e antigen (HBeAg) isolated from sera of asymptomatic carriers of hepatitis B virus. Their spleen cells were fused with mouse myeloma (NS-1) cells, and 5 clones of hybridoma cells secreting antibody against HBeAg (anti-HBe) were isolated. For the production of anti-HBe in large scale, cells were cultivated both in vitro and in the peritoneal cavity of ascitic mice. Although monoclonal antibodies produced by these clones showed a strong reactivity of anti-HBe in hemagglutination tests, individual monoclonal anti-HBe did not reveal any precipitin line in immunodiffusion. When 2 of the 5 monoclonal antibodies were mixed together, however, some combinations showed a precipitin line against HBeAg, whereas others did not. Utilizing solid-phase radioimmunoassay involving a number of combinations of monoclonal antibodies used for solid-phase and radiolabeling, the 5 antibodies were classified into 2 groups. Three of the anti-HBe antibodies were found to be directed to 1 determinant of HBeAg (determinant a); the remaining 2 to the other determinant (determinant b). Determinants a and b were detected on HBeAg in the serum, as well as on the polypeptide of 19,000 daltons (P19) derived from the nucleocapsid of hepatitis B virus. Monoclonal anti-HBe antibodies with different specificities may provide useful tools in delineating the antigenic structure of HBeAg and also in evaluating immune responses of the host directed to its subdeterminants.

Demonstration of two distinct antigenic determinants on hepatitis B e antigen by monoclonal antibodies

Mice were immunized against hepatitis B e antigen (HBeAg) isolated from sera of asymptomatic carriers of hepatitis B virus. Their spleen cells were fused with mouse myeloma (NS-1) cells, and 5 clones of hybridoma cells secreting antibody against HBeAg (anti-HBe) were isolated. For the production of anti-HBe in large scale, cells were cultivated both in vitro and in the peritoneal cavity of ascitic mice. Although monoclonal antibodies produced by these clones showed a strong reactivity of anti-HBe in hemagglutination tests, individual monoclonal anti-HBe did not reveal any precipitin line in immunodiffusion. When 2 of the 5 monoclonal antibodies were mixed together, however, some combinations showed a precipitin line against HBeAg, whereas others did not. Utilizing solid-phase radioimmunoassay involving a number of combinations of monoclonal antibodies used for solid-phase and radiolabeling, the 5 antibodies were classified into 2 groups. Three of the anti-HBe antibodies were found to be directed to 1 determinant of HBeAg (determinant a); the remaining 2 to the other determinant (determinant b). Determinants a and b were detected on HBeAg in the serum, as well as on the polypeptide of 19,000 daltons (P19) derived from the nucleocapsid of hepatitis B virus. Monoclonal anti-HBe antibodies with different specificities may provide useful tools in delineating the antigenic structure of HBeAg and also in evaluating immune responses of the host directed to its subdeterminants.

Demonstration of the immunogenicity of hepatitis B core antigen in a hepatitis B e antigen polypeptide (P19)

The core of Dane particles, the presently accepted hepatitis B virus nucleocapsid, contains two polypeptides (P19 and P45) with the antigenicity of hepatitis B e antigen (HBeAg). The antigenicity of hepatitis B core antigen (HBcAg) was not detectable in either of them by the conventional in vitro assay methods, despite the fact that both of these polypeptides were derived from the core of Dane particles. When a rabbit had been immunized with the purified preparation of P19 emulsified in complete Freund's adjuvant, however, humoral antibody against HBcAg was produced in addition to the antibody against HBeAg. Amino acid analysis of P19 disclosed a high content of arginine (12.9%), leucine (11.9%), serine (10.3%) and proline (10.2%). The amino acid composition of P19 was found to be strikingly similar to the composition of the 183 amino acid sequence deduced from the sequence of hepatitis B virus DNA which has been presumed to be encoding HBcAg. We conclude that both HBeAg and HBcAg are antigenic determinants borne by the major polypeptide (P19) constituting the core of Dane particles.

Defective immune-adherence (C3b) receptor on erythrocytes from patients with systemic lupus erythematosus

Erythrocytes from 56 patients with systemic lupus erythematosus (SLE) were tested for the immune-adherence (C3b) receptor reactivity for incubation with aggregated human gamma-globulin (AHG) in the presence of complement. The reactivity of the C3b receptors was expressed as the highest two-fold dilution of AHG that induced haemagglutination. Erythrocytes from 37 (66%) of the SLE patients failed to show any detectable reactivity with AHG, whereas the erythrocytes of only 1 of 51 normal controls matched for age and sex were found to be unreactive. The defect of the C3b receptor reactivity was persistent and could not be restored even after SLE patients had gone into remission with steroid therapy. Moreover, the defect was found frequently in the relatives of patients without detectable immune-adherence reactivity. Owing to its high prevalence and persistence in SLE, the defective erythrocyte C3b receptor may be a useful marker for identifying SLE patients and those predisposed to the disease.

Demonstration of two different types of non-A, non-B hepatitis by reinjection and cross-challenge studies in chimpanzees

Utilizing immune electron microscopy, viruslike particles were identified in the serums of three apparently healthy, HBsAg-negative blood donors. The serum from one of the donors, when injected into two susceptible chimpanzees, induced non-A, non-B hepatitis with an increase in SGPT level and pathological changes in the liver compatible with acute hepatitis but none of the cytoplasmic ultrastructures previously noted by electron microscopy in non-A, non-B hepatitis. These two chimps did not contract hepatitis when the same inoculum was given again 17 wk after the first injection. When they were subsequently challenged, however, by a chimp inoculum containing viruslike particles known to induce non-A, non-B hepatitis with cytoplasmic tubular ultrastructures, they developed high SGPT levels and these characteristic ultrastructures in their hepatocytes. A third chimp was initially injected with the chimp inoculum containing viruslike particles known to induce hepatitis with tubular ultrastructures, reinjected with the same agent, and then challenged by the human serum containing viruslike particles capable of inducing non-A, non-B hepatitis without tubular ultrastructures. He developed biochemical and pathological evidence of acute hepatitis after the first and the third, but not after the second inoculations. There are at least two kinds of viruslike particles which are associated with infectivity for two different types of non-A, non-B hepatitis; these have been tentatively designated NANB-1 and NANB-2.