Search

Lyme borreliosis is a tick-borne infection caused by the spirochete Borrelia burgdorferi, whose discovery in 1982 solved an aetiological mystery involving a variety of dermatological and neurological disorders and explained their association with Lyme disease. Lyme borreliosis occurs frequently and is readily treatable with antibiotics. Along with its discovery, however, came the realization that it is difficult to diagnose accurately, especially antibody diagnosis. False-positive antibody results in particular led to gradual widening of the clinical spectrum, and differential diagnosis became increasingly difficult. This prospective, multicentre study presents a systematic description of Lyme borreliosis in childhood, emphasizing epidemiological and clinical issues. Because, predominantly, inpatients were examined, Lyme neuroborreliosis was the focus of the study, with the chief concern being to minimize false-positive results. To this end, we chose to narrow the diagnostic criteria, using the presence of specific antibodies in the cerebrospinal fluid as the determining factor. The epidemiological investigation was focused on the incidence of Lyme neuroborreliosis in childhood in southern Lower Saxony as well as on the prevalence of Lyme neuroborreliosis among acute-inflammatory neurological illnesses in children. The clinical part of the study aimed at establishing criteria for differential diagnosis in addition to the detection of specific antibodies. The detection of specific IgM antibodies using an IgM capture ELISA confirmed the presence of acute Lyme borreliosis. The study examined 208 children with Lyme borreliosis, of whom 169 had Lyme neuroborreliosis, from mid-1986 until the end of 1989. The yearly incidence of Lyme neuroborreliosis in Lower Saxony was 5.8 cases/100,000 children aged 1 to 13. The manifestation index was 0.16, or one case of Lyme neuroborreliosis per 620 infected children, compared with the presence of specific antibodies against B. burgdorferi for children in the same age group and region. Both the seasonal distribution of Lyme borreliosis, which peaked in summer and autumn, as well as the information about when the tick bites took place point to an incubation period of a few weeks. The most frequent manifestation of Lyme neuroborreliosis in childhood was acute peripheral facial palsy, found in 55% of all cases (n = 93). Lyme borreliosis proved to be the most frequently verifiable cause of acute peripheral facial palsy in children, causing every second case of this disorder in summer and autumn.(ABSTRACT TRUNCATED AT 400 WORDS)

During the assembly of the nucleocapsid of the hepatitis B virus a protein kinase, probably of cellular origin, is encapsidated. This enzyme phosphorylates serine residue(s) localized within the lumen of the particle. By using purified, liver-derived core particles, we characterized the protein kinase activity in the presence of different ions and inhibitors. Controls were performed with cAMP-dependent protein kinase (PKA) and protein kinase C (PKC) and recombinant core particles. We showed that the endogenous protein kinase of the core particles was not inhibited by H89, a specific inhibitor of PKA. Staurosporine, a selective inhibitor of PKC inhibited the endogenous kinase activity only within the first minutes of the reaction. In contrast, quercetine, a selective inhibitor of the protein kinase M (PKM) did not inhibit during the first minutes but inhibited efficiently during later phases of incubation. PKM represents an enzymatically active proteolytic fragment of PKC. These results suggest that PKC is encapsidated into human core particles and is converted to PKM during the in vitro reaction. This conclusion implies the association of a protease activity localized with the HBV nucleocapsid inside liver-derived core particles.

Hepatitis C virus (HCV)-RNA in sera of patients with viral hepatitis C is supposed to be included, at least partially, into HCV particles. We found that the density of HCV-RNA-carrying material was variable, as determined by sucrose gradient density centrifugation (1.03-1.20 g/cm3). In some of the sera examined HCV-RNA was restricted to low densities between 1.03 and 1.08 g/cm3. In other sera additional densities of HCV-RNA were found distributed over the whole gradient with peaks at 1.12 and 1.17 and at 1.19-1.20 g/cm3. HCV-RNA banding at low densities could be completely co-precipitated with anti-beta lipoprotein, whereas HCV-RNA fractions of higher densities were only partially precipitated or not at all. In 8 of 20 sera directly examined, HCV-RNA could be completely and in 9 sera only partially co-precipitated by anti-beta lipoprotein. In 3 sera no significant precipitation could be observed.

Sera from 118 women of 33 to over 90 years of age, with or without a history of cervical squamous-cell carcinoma, were examined for the presence of antibodies to HPV-6b, HPV-16 and HPV-18, L1, L2, E4, and E7 gene products by the use of bacterially derived beta-Gal fusion proteins and Western-blot analysis. Among the cervical cancer patients, 29/46 (63.0%) were positive for antibodies to E4 and/or E7 of HPV-16 and/or E7 of HPV-18. In contrast, only 2 of 31 (6.5%) non-genital cancer patients and 4 of 41 (9.8%) healthy individuals were antibody-positive for HPV-16 E4 or E7, while antibodies to the homologous proteins of HPV-18 could not be detected. Prevalence rates of antibodies to the HPV-16/18 late proteins were 25/46 (54.3%) in the cervical carcinoma group, 13/31 (41.9%) among women with non-genital cancer types, and 18/41 (43.9%) among normal, healthy individuals. Antibodies to HPV-6b late gene products ranged between 6.5% and 12.2% in the different patient groups. Antibodies to HPV-6b E4 and E7 were detected only once. By studying an additional control group of 207 women with a different age distribution, age-dependence of antibodies to HPV gene products could be ruled out. Whereas antibodies to late proteins may indicate that, regardless of clinical stage, HPV infections are wide-spread among the female population, the striking difference between the prevalence rates of antibodies to early proteins of HPV-16 and HPV-18 among cervical cancer patients and controls (p less than 0.001) supports the idea of the involvement of these virus types in carcinogenesis of the cervix.

The hepatitis B virus, although containing a DNA genome, replicates by reverse transcription of an RNA pregenome. The viral Pol gene encodes the reverse transcriptase which catalyzes viral DNA synthesis. To study the interaction of this protein with HBV RNA, the entire Pol gene product was expressed except its eight amino-terminal codons in Escherichia coli as fusion protein with beta-galactosidase. In the absence of competing nucleic acids full-length expression products were able to nonspecifically bind in vitro synthesized HBV RNAs of different polarity and length. However, if competed with an excess of unspecific RNA, only those HBV RNAs were bound which contained besides the direct repeats 1 and 2 nucleotide sequences downstream of direct repeat 1. The corresponding binding site was found to be located within the adjacent 134 nucleotides downstream of DR1. We conclude from our data that this region which is in part homologous to the U5 region of retroviral genomes may be important for the binding of the HBV Pol gene product to the viral pregenome.

We have developed a modified ELISA for the detection of anti-Borrelia burgdorferi (Bb) antibodies based on a peroxidase enzyme labelled antigen (ELAT). Microtiter plates were coated with antigen of Bb. The immunoglobulins of the serum samples were bound to the antigen and specific antibodies were detected by an enzyme labelled antigen. The test principle facilitates the recognition of specific antibodies in different collectives of human and animal sera. We performed epidemiological studies with the ELAT on 231 sera from mothers in maternity wards (9.5% positive), 219 patient sera sent to the Bb routine diagnostics (15% positive) and 230 sera from forestry workers (21.3% positive). We further investigated sera from red deer from South Lower Saxony which remained 55% Bb-antibody positive; deer were 37% and fallow deer were 29% positive.

Investigations of immunoblots using Borrelia burgdorferi antigen demonstrated that a band, migrating faster than the bromophenol blue front in sodium dodecyl sulfate-gel electrophoresis, reacted strongly with sera containing anti-Borrelia burgdorferi antibodies preferentially of the IgG class. Extraction of this antigenic component and chemical analyses showed that the substance was composed mainly of fatty acids and carbohydrates. Typical structures of classical lipooolysaccharides such as 3-deoxy-D-manno-2-octulosonic acid, hydroxy fatty acids or lipid A could not be detected.

Generalized adenopathy and splenomegaly developed in an 18-year-old youth after a severe tonsillitis followed by headache, tiredness and weight loss for several weeks. Infectious mononucleosis (acute Epstein-Barr virus infection) was confirmed by the demonstration of virus-specific antibodies. A reticulocytosis (24%), decreased haptoglobin concentration (0.6 mg/dl) and increased lactate dehydrogenase activity (657 U/l) indicated marked haemolysis. The bone marrow showed increased erythropoiesis with abnormal maturation. Antibodies against triosephosphate isomerase and against blood group marker "i" were demonstrated in the patient's serum. Antibodies against triosephosphate isomerase from the patient's serum were purified by affinity-chromatography. They strongly reacted with the patient's erythrocytes and under complement activation induced an increased 51Cr liberation from marked erythrocytes. No corresponding effect of anti-i-antibodies was noted at 37 degrees C. With the fall in antibodies against triosephosphate isomerase the haemolysis receded and the patient became free of symptoms after 7 weeks.

The current recombinant hepatitis B vaccines are safe and effective. However, the occurrence of non-responders and difficulties in immunizing immunodeficient persons suggest the need for further improvements. Recent data suggest that the pre-S2 and pre-S1 domains of hepatitis B virus induce protective antibodies. The good T-helper cell response against pre-S1 epitopes would also improve the antibody response against the small surface antigen protein. An even better T-cell priming could be achieved by including hepatitis B core (HBc) proteins or peptides. An optimal immunogen would contain all three proteins comprising hepatitis B surface antigen in their natural conformation and glycosylation as well as the major T-cell epitopes of HBc.

The DNA fragment of the human parvovirus B19, with 715 nucleotides between nucleotide positions 3141-3856 was expressed in Escherichia coli as a beta-galactosidase fusion protein. The plasmid vector pSS20d used for this purpose permits cleavage of the viral gene product from the beta-galactosidase moiety by collagenase. After purification by p-aminophenyl-beta-D-thiogalactoside-sepharose and superose, a soluble protein with a molecular mass of 28 kDa was isolated. It represents a common part of the viral capsid proteins VP1 and VP2. This bacterially derived parvoviral gene product can be used for detection of anti-B19 antibodies in human sera.

In the course of infectious mononucleosis, IgM antibodies are formed against 2 proteins present in nucleated and non-nucleated vertebrate cells. Antibodies were found in sera of all patients suffering from acute Epstein-Barr virus infection. In 40% of the cases these antibodies are monoclonal. Persons with former Epstein-Barr virus infection were negative. The antibodies against the 2 proteins were first detected in Raji cells with an IgM-specific immunofluorescence test. The proteins were demonstrated in extracts of different cells and tissues by immunoblot technique. The molecular weight of the proteins measured in SDS polyacrylamide gel electrophoresis was 26 kd and 29 kd, respectively. Their presence in the cells does not depend on the presence of the Epstein-Barr virus genome. The relevance of the new findings concerning diagnostics as well as pathogenetic aspects remains to be established.

The diagnostical significance of the large hepatitis B surface protein with its preS1 attachment site and of anti-preS antibodies are not yet well known. We investigated the epitope of the preS1 attachment site to see whether it is a marker of viremia and whether antibodies against it occur in convalescents and vaccinees. For comparison, sera were also tested for the presence and relative amount of a preS2 epitope. The epitopes were detected by binding to specific monoclonal antibodies (mAb MA18/7 for the preS1 epitope and mAb Q19/10 for the preS2 epitope) at the solid phase of a sandwich enzyme-linked immunosorbent assay. Antibody against the preS1 epitope was detected by inhibition of binding to mAb MA18/7. This mAb inhibits attachment of preS1 antigen to hepatocytes and reacts with a subtype-independent sequential epitope at the surface of hepatitis B virus between amino acid 29-36. This preS1 epitope occurs in most hepatitis B surface antigen (HBsAg) carriers, irrespective of viremia. Free preS2 epitope Q19/10 is present in samples with more than 8 micrograms/ml total HBsAg and it is masked in sera with less HBsAg. Antibodies which compete with mAb MA18/7 for its viral preS1 epitope occur in one third of HBsAg carriers who were negative for hepatitis B e antigen. It also occurs in one third of convalescents and in most good responders to plasma-derived vaccines.

Using direct solid-phase radioimmunoassay (dSP-RIA) which was shown to be specific and about 10000 times more sensitive than immunodiffusion and even 10 times more sensitive than the radioimmunoprecipitation test used by us before, anti-HBs was detected in 90% of hepatitis B convalescents who were followed up for a one year observation period and who had eliminated HBs antigen from their sera (60/68). In 13% of these patients (8/60 anti-HBs was only temporarily detectable. In 50% of all patients who developed antibody within a two to twelve months observation period (n = 151), anti-HBs appeared within three to four months after height of disease. In 16.5% of patients with HBs antigen negative hepatitis (32/193) anti-HBs was observed to develop during convalescence indicating a type B infection despite a negative finding for HBs antigen in the acute stage of disease. Using dSP-RIA anti-HBs was found in 5.5% of voluntary blood donors (n = 1036), in 20.2% of hospitalized patients without clinical hepatitis (n = 252), and in 30.6% of hospital staff (n = 304). Anti-HBs increases with age: in 14 year olds we found 0.5%, in 60 year olds, 14%. The fact that at least 70% of the anti-HBs positive normal persons and medical staff groups had no history of hepatitis illustrates the frequency and importance of subclinical hepatitis B infections.

A method for quantitative standardization of the DNA hybridization assay for hepatitis B virus (HBV) DNA protein complex in serum is described. This method was used to determine the titer of HBV DNA in various groups of subjects with HB surface antigen (HBsAg) in order to ascertain its accuracy as an index of infectivity. The method's detection limit was 10(5) genome equivalents or 0.3 pg DNA per ml. Titers of 5 X 10(7) to 5 X 10(8) genome equivalents per ml were found to be typical for persistent massive viremia, which occurred more frequently in symptomatic (30 of 48) than in asymptomatic (24 of 72) carriers positive for HBe antigen (HBeAg). Moderate viremia (10(5)-5 X 10(7)) was usually found in patients eliminating the virus from the blood. Patients with resolving acute hepatitis B were frequently positive at the onset (18 of 26) with moderate titers, but became negative within several weeks. In 11 patients who developed chronic hepatitis B, titers increased until typical massive viremia was evident. Whereas healthy HBsAg carriers with anti-HBe always had negative genome titers (144 of 144), symptomatic carriers with anti-HBe often had moderate genome titers (9 of 30). It is recommended that genome titers be monitored in HBeAg-positive and in symptomatic anti-HBe positive virus carriers in order to distinguish between virus carriers with high (greater than 5 X 10(7)), moderate (10(5) -5 X 10(7)) and low (less than 10(5)) infectivity.

Stimulated macrophages are known to inhibit the growth of certain tumor cells. Using mouse peritoneal exudates as a source of macrophages and the mastocytoma cell line P815 as the target, the inhibition was found to depend on direct contact between the macrophages and the growing cells. Cytostatic activities were detected in extracts of macrophages as well as in membranes of macrophages bound to substances of low molecular weight. Physical and biochemical characteristics of the cytostatic activity hint toward N-acetylneuraminic acid containing glycosphingolipids (gangliosides). The different macrophage gangliosides were separated by thin-layer chromatography. All types showed cytostatic activity, but the most effective gangliosides were identified as monosialoganglioside GM1 and disialoganglioside GD3.

A specific and sensitive solid-phase radioimmunoassay has been developed for the detection of LCM virus antigens and anti-LCM virus antibodies. The test was performed in a microtiter system using polyvinylcholoride wells coated with anti-LCM virus rabbit hyperimmune serum. LCM virus antigens were allowed to bind to this antibody and afterwards detected by 125J-labeled anti-LCM virus-gamma-globulin. Anti-LCM virus antibodies were assayed by specific inhibition of these bound antigens. Since this technique is rapid and easy to perform the solid-phase radioimmunoassay is a valuable test for detecting LCM virus infections. Selected at random, 208 girls with, and 208 girls without, contact to Syrian hamsters were investigated for anti-LCM virus antibodies. Five (2.4%) of the hamster-exposed girls had anti-LCM virus antibodies (RIA-titer 1:8-1:32) in contrast to none of the control group (P=0.03).

A prospective hospital-based multicentre study in Lower Saxony allowed to investigate the frequency of acute peripheral facial palsy due to Lyme borreliosis and its clinical and laboratory characteristics. Diagnosis of Lyme Borreliosis was based on detection of IgM antibodies against Borrelia burgdorferi in serum and CSF as well, using an IgM capture ELISA. Between June 1986 and October 1987 27 consecutive cases with acute peripheral facial palsy were studied. Lyme borreliosis is the main cause of peripheral facial palsy in childhood. It was verified serologically in two thirds of the cases. All cases with a positive history for a tick bite and/or an erythema migrans in the head-neck region showed ipsilateral neurological affection suggesting a direct invasion via the affected nerve by Borrelia burgdorferi. Peripheral facial palsy due to Lyme borreliosis represents a monosymptomatic meningoradiculitis. All children with Lyme borreliosis revealed a lymphocytic CSF pleocytosis, whereas in cases of unknown etiology CSF findings usually were normal. Therefore, in any case of facial palsy with an inflammatory CSF syndrome Lyme borreliosis has to be suspected unless proven otherwise.

The disc agar-diffusion-test using Bacillus subtilis ATCC 6051 as test organism is a simple and rapid method for routine testing of antibacterial agents in urine specimens. The test records urine levels which are expected under medium dosage, and in many cases even lower concentrations of renal excreted antibiotics. Out of 5655 analysed urine samples 22% contain antibacterial substances. In urine specimens over which information was volunteered that either no chemotherapy had been administered or that more than a three day's interval free of therapy existed, inhibitory substances are found in 8% and 27% respectively. Urine specimens which are supposedly collected from patients under current chemotherapy do not show therapeutic relevant antibiotic levels in 26%. Between urine specimens with and without antibacterial activity there is no significant difference in the incidence of viable counts of 10-4-10-5/ml and 10-5/ml. From urine samples with antibacterial content increases in the numbers of multiple resistant strains of E. coli, Proteus spp., Pseudom. aerug. and Enterobacter spp. together with high numbers of Candida spp. are observed.

Hepatitis B surface antigen (HBsAg) was purified from human plasma by gel chromatography, isopyknic centrifugation, and zonal centrifugation. The final product had about 60% of the original activity and was essentially free from hepatitis B virus particles (HBV) and plasma proteins. Treatment with formaldehyde concentrations up to 0.1% for inactivation of residual infectivity did not significantly reduce antigenicity in vitro and immunogenicity in guinea pigs. Adsorption to aluminum hydroxide resulted in 16-fold higher concentrations of antibody against HBsAg (anti-HBs) than did injection of soluble HBsAg. After two injections of 0.2 microgram HBsAg, which was treated with 0.1% formaldehyde and absorbed to aluminum hydroxide, the median titer of anti-HBs in guinea pigs was 4 IU/ml (normal value in human hepatitis B convalescents: about 0.1) for 1 year without further injections. When guinea pigs received 12 equivalents of homologous anti-HBs serum before the first injection of adsorbed HBsAg, the same anti-HBs titers were found after the booster injection as in animals which had not been passively immunized. A simultaneous application of an experimental HBsAg vaccine and hepatitis B immunoglobulin would probably decrease the potential risk of HBV infections caused by the vaccine itself and also produce rapid protection. To establish absence of HBV as completely as possible, the vaccine should be produced from anti-HBe-positive plasma by efficient purification procedures and it should be inactivated by formalin.

LCM virus, strain WE--grown on L cells--and labeled with 3H-uridine was centrifuged to equilibrium in a sucrose density gradient and examined in fractions for infectivity, incorporated radioactivity, and electron-microscopic features. The peak of infectivity is congruent with the one of radioactivity (density = 1.17 g/ml). LCM virus specificity of the radioactive peak was proved by precipitation of the radioactivity with anti-LCM virus antiserum. The peak fractions showed an abundance of 106 +/- 14 nm (1s) particles. They could be agglutinated with specific anti-LCM virus antiserum but not with antiserum directed against the histocompatibility (H-2) antigens of L cells.

Cell mediated immunity to vaccinia virus in man was studied by lymphocyte transformation. Vaccinia antigen, propagated on BHK-21 and Vero cells, could be used successfully for in-vitro testing after partial purification as well as crude infectious homogenates. Vaccinia antigen preparations were effective both in the infective and the inactivated state. Inactivation was usually accompanied with a certain loss of stimulating activity. Development of cell mediated immune response in-vitro after first vaccination was investigated in 17 adults. Vaccinia virus specific lymphocyte transformation was seen in the second week after vaccination in all cases. Following revaccination no increase of lymphocyte transformation ratio could be observed in 11 persons studied. At the same time the titers of humoral antibodies were elevated.

Starting with 41.5 l of plasma from anti-HBe positive carriers of HBs antigen, 11,400 doses of a hepatitis B vaccine with 42 micrograms HBsAg-protein and 11,300 national units HBsAg activity per dose were obtained. After purification, HBsAg is obtained in 99% purity with a yield of more than 90% protein. A possible residual infectivity was inactivated by a diluted formalin solution. The infectivity test in chimpanzees confirmed the absence of infectious hepatitis viruses (HBV and nonA-nonB). In guinea pigs the immunogenicity of the vaccine was comparable to that of the reference preparation from the U.S. National Institute of Health. The presence of Al(OH)3 in the vaccine increased the anti-HBs titre by factors of 30-50. After vaccination with two doses 41 of 45 persons became anti-HBs positive, with three doses 42 of 45 persons developed anti-HBs. Median anti-HBs titre after the third doses: schedule I (three doses in intervals of 6 weeks) 427 mWHO-U/ml; schedule II (two doses at an interval of 4 weeks, third doses 4 months after the first doses) 1535 mWHO-U/ml. The vaccine was well tolerated. There were minor local reactions only.

Using recombinant DNA methods, many different approaches may be followed to optimize immunoprophylaxis against hepatitis B viruses. Most obviously a future vaccine should contain besides the known major surface protein two further envelope proteins which have recently been identified. All three envelope proteins should be present on the same particle in natural proportion and conformation. Such a vaccine may induce a more reliable and more durable immune protection even in difficult cases. The protective potential of the viral core protein, in particular of HBeAg, ought to be studied further experimentally. Possibly, the core proteins may be helpful in an immune therapy of already infected persons.

No experimental setting is available to exclude residual infectivity in HBsAg vaccines derived from human plasma. Thus, safety can be achieved only by means of their preparation. To reduce infectivity of the starting material, only plasma from healthy anti-HBe positive donors was used. In the FRG, 50% of all healthy HBsAg carriers with anti-HBe have a suitable serum level of 5 to 20 micrograms/ml. The purification procedure removed hepatitis B virus by a factor greater than 10(4). The purified product contained only the HBsAg proteins and no serum protein, as shown by SDS gel electrophoresis. The pure HBsAg was treated with formalin 1:500 at 37 degrees C for 4 days. A loss of 30 to 50% antigenicity was tolerated to achieve the highest possible destruction of known and unknown infectious agents. After inactivation, the HBsAg was bound to aluminium hydroxide gel. The gel was washed repeatedly to remove the formalin. Doses of 40 micrograms or 20 micrograms absorbed HBsAg protein were given to greater than 2500 persons without serious side effects. In greater than 97% anti-HBs was formed with a median titer of 1900 I.U./ml.

Three groups of subjects (58 females, 54 heterosexual males, and 50 homosexual males) received three doses of a recombinant DNA yeast-derived hepatitis B vaccine according to a 0, 1, and 6 month vaccination schedule. Local and general side effects were mild. Seroconversion rates after three injections were not significantly different between the groups. Females showed a significantly higher anti-HBs response than both groups of males, and heterosexual males had higher antibody titres than homosexual males. Among the four homosexual non-responders, three were carriers of the human immunodeficiency virus.

The protective effect of anti-HBs against hepatitis B virus is proven only for the common antibody anti-HBs/a but not for subtype specific antibody. Using subtype specific radioimmunoassays, anti-HBs/a and anti-HBs/d were quantitated in recipients of an HBsAg/ad vaccine. All persons developed anti-HBs/a. The relative proportion of anti-HBs/d was variable and very high at the beginning of the immune response. At this time the anti-HBs was predominantly in the IgM class. IgM-anti-HBs disappeared rapidly after its peak value and was more slowly replaced by IgG-anti-HBs. Persons who had only anti-HBs or anti-HBc as the only antibody did usually not react with an anamnestic booster response and developed IgM- anti-HBs after vaccination. An injection schedule of 0, 1, 4 months produced ten times higher titers than a 0, 1.5, 3 months schedule 4 weeks after the third injection. However, 6 months later titers were essentially identical. Nine of ten "non-responders" became positive after a fourth injection.

Hepatitis B virus (HBV) DNA contains a precore (pre-c) sequence of 29 codons with unknown function upstream of its gene for the major core protein. Its significance was studied by expression of core proteins with and without pre-c in Escherichia coli. Core protein without pre-c, P22c, assembled spontaneously to core particles and formed core antigen. It had the same size and antigenicity as core particles from infected liver. Core protein with pre-c, P25e, instead formed membrane-associated e antigen (HBeAg). The data suggest that pre-c functions as a signal peptide for the attachment of core protein P25e to cellular membranes. This hypothesis can explain the not yet understood relation between viremia and HbeAg and the protective role of anti-HBe antibody.

The frequency of hepatitis B was examined using three serological parameters: HBsAg, antiHBs and antiHBc. All three substances were detected qualitatively by means of sensitive radioimmunological techniques. Of 1216 patients with acute hepatitis, 55 percent were HBsAg and antiHBc positive on admission to hospital. A further 17.8 percent had no HBsAg but were antiHBc positive and also partly antiHBs positive. These cases can be divided into 2 groups: In one group, in 8.6 percent of patients had a high antiHBc concentration during the acute phase. Similar antiHBc concentrations were seldom found (0.04 percent) in HBsAg negative blood donors. AntiHBs in the patients was at first mainly negative and then appeared during reconvalescence. These cases were considered to be acute hepatitis type B, although HBsAg was absent. In the second group, comprising 9.2 percent of the patients, antiHBc was present in low concentrations and in majority of cases antiHBs had been present from the beginning. The same antibody constellation was found in 3.6 percent of 2341 blood donors. In the group of patients it is supposed that the acute hepatitis present is not of type B and has a different aetiology. The low concentration of antibody is interpreted to be a sign of an earlier HBV-infection.

On the occasion of an outbreak of non-A, non-B hepatitis in a plasmapheresis centre (81 cases, incubation period: 3--6 weeks) a pool of 12 plasma samples was obtained in the early phase of increasing transaminases. Two chimpanzees were inoculated, each receiving 12 ml of the pooled plasma. After an incubation period of 10--12 weeks a mild non-A, non-B hepatitis developed. Serum transaminases were slightly elevated. Needle biopsies, taken fortnightly, showed a slight activation of Kupffer cells (6--8 weeks), single cell necroses, and infiltration of the portal tracts (10--13 weeks). Electron microscopically four types of cytoplasmic change, were found in hepatocytes and assumed to be specific for the infection, Type I: Sponge-like inclusion (6 weeks after inoculation) composed of a dense matrix and irregularly arranged membranes. Type II: Attaching curved membranes (8 weeks), developing by close apposition of two cisternae of smooth endoplasmic reticulum. Type III: Cylindrical complexes (10 weeks), already described in literature. Type IV: Microtubular aggregates, usually neighbouring type III structures. The findings suggest 1) that the agent of the present infection is, at least in part, identical with that of the long incubation type of experimental non-A, non-B hepatitis, and 2) that ultrastructural alterations may precede manifest hepatitis.

IgM antibody to hepatitis B core antigen (anti-HBc) was determined by a reverse enzyme immunoassay. In all of 58 patients with transient hepatitis B surface antigen (HBsAg)-positive acute hepatitis, IgM anti-HBc was detected in high titer. In 79.3%, IgM anti-HBc disappeared within two years, but in the remaining 12, it was still detectable. In 20 of 21 patients who developed chronic hepatitis, IgM anti-HBc was present after two years. High titers of IgM anti-HBc were found in 13 patients with histologically confirmed hepatitis B in whom HBsAg could not be detected in the initial serum samples; 11 of them later developed antibody to HBsAg and/or e antigen. Furthermore, IgM anti-HGc was detected in eight (5.6%) of 142 HBsAg-negative blood donors with elevated levels of serum transaminases and in 11 (0.5%) of 2,400 HBsAg-negative blood donors with normal levels of serum transaminases. Thus, IgM anti-HBc might be a better indicator of hepatitis B than HBsAg and help differentiage acute from chronic infection in HBsAg-positive patients.

Many investigators in Europe and the USA have usually found high rates of serum conversion after vaccination with the rubella vaccines Cendehill and RA 27/3, but the resistance of vaccinated individuals against superinfection without disease induced by wild virus strains under experimental or natural conditions seems to be very low; e.g. up to 80% of the vaccinees reacted with increasing titers of hemagglutination inhibiting antibodies after super-infection with a wild virus in a special epidemiological situation. In our two studies performed under natural conditions of infection including an observation period of three years resp. five years after vaccination a more favourable picture evolved, perhaps reflecting a different epidemiological situation, a different susceptibility or a less virulence of wild virus in our region: Three years after vaccination of 14 years old girls with Cendehill and RA 27/3 in a double blind trial a significant increase in the titers of hemagglutination inhibiting antibodies was observed after vaccination with Cendehill by the subcutaneous route in only 1,16% (1/86) and in 1,18% (1/85) after vaccination with RA 27/3 by the same route. In the same observation period the infection rate in a control group not protected by natural immunity or by vaccination was 54,72% (87/159) and in a second control group, protected by natural immunity 1,82% (3/165)...