Seroprevalence of parvovirus B19 NS1-specific IgG in B19-infected and uninfected individuals and in infected pregnant women.

Parvovirus B19 is the causative agent of erythema infectiosum in children, but the virus is associated with an increasing range of different diseases. These include acute and chronic arthritis, hydrops fetalis in pregnant women, aplastic anemia, and thrombocytopenia. The host's immune response is directed against the viral structural proteins VP1 and VP2. This study investigated the presence of IgG against the viral nonstructural protein NS1 using Western blot. Serum panels from healthy individuals, B19-infected pregnant women, and various disease groups were tested. The disease groups included patients with symptoms that may be linked to parvovirus B19 infection. The results showed that IgG against the NS1 protein was present in 22% of healthy individuals with past B19 infection. In cases of persistent or prolonged B19 infections, the prevalence of NS1-specific antibodies was as high as 80%. It is concluded that NS1-specific IgG may be used as an indicator of chronic or more severe courses of parvovirus B19 infections.

Acute parvovirus B19 infection in connection with a flare of systemic lupus erythematodes in a female patient.

BACKGROUND: Since its discovery parvovirus B19-infections could be linked to a growing variety of diseases. Besides the harmless exanthema erythema infectiosum perferentially observed with B19-infections in childhood a panel of rather serious and also chronic courses that may be associated with anemia, thrombocytopenia, arthritis and others have been described. OBJECTIVE: In a 26-year-old female patient an acute parvovirus B19-infection was followed by a serious episode of systemic lupus erythematosus (SLE). Here we demonstrate the clinical and serological parameters which were observed in the patient during that episode in addition to the nucleotide sequence of the virus isolate. RESULTS AND CONCLUSION: In this patient parvovirus B19 was not the initial causative agent for SLE. However the B19 infection was followed by a severe flare of SLE and therefore may be considered as an enhancer of the autoimmune disease. The amount of nucleotide variability observed in the viral genome was in the range known from other B19 isolates. An elevated degree of mutations in antigenic domains was not detectable. Therefore, we would like to emphasize the possible role of parvovirus B19 in the aetiology or the enhancement of autoimmune diseases like SLE and the necessity of an according differential diagnosis.

Hyaluronidase enhances the activity of adriamycin in breast cancer models in vitro and in vivo.

The effect of hyaluronidase and a combination of hyaluronidase with Adriamycin was investigated on several breast cancer models in vitro and in vivo. In vitro enzyme treatment (using concentrations up to 80,000 IU/1) of murine (MXT-, MXT +/-, and MXT+) and human (MCF-7, ZR-75-1 and T-47-D) breast cancer cell lines did not inhibit tumour cell proliferation (measured by a kinetic crystal violet assay) in either case. Although high-dose hyaluronidase (1.2 x 10(6) IU/kg) was ineffective, when administered peritumourally to the MXT M3.2 mammary carcinoma of the B6D2F1 mouse, it is remarkable that five "megadoses" were excellently tolerated. However, the antineoplastic activity of Adriamycin against the oestrogen-receptor-positive variant of the MXT tumour was significantly enhanced by combination with concentrations of hyaluronidase that were inactive per se, both in vitro and in vivo. Interestingly, the enhancement of the in vivo antitumour activity was not compromised by toxic side-effects.