Effect of local interleukin-2 treatment on spontaneous tumours of different immunogenic strength

Transplantable tumour lines established from spontaneous tumours of BALB/c, CBA, and DBA/2 mice displayed different immunogenic strength. This report describes tumour susceptibility to interleukin-2 (IL-2) therapy in relation to tumour immunogenicity. The following tumour lines were used: X5, X6, and X9 mammary tumours of DBA/2, BALB/c, and CBA origin respectively, X7 carcinoma of BALB/c and X18 papilloma of CBA mice. Two spontaneous tumours of long transplantation history, SL2 lymphoma (SL2) of DBA/2 and Madison lung carcinoma M109 (M109) of BALB/c origin, were used as control systems. Experimental mice were transplanted with different inocula of tumour cells at day 0; treatment with IL-2 was initiated on days 1–3 or delayed until day 10 and consisted of daily injections of low doses of 5000 or 20 000 U/mouse given five times a week for a period of 3 weeks. Treatment of SL2 (2 × 10⁴ cells injected i.p.) consisted of i.p. injections of 5000 or 20 000 U IL-2/mouse given on days 10–14 after tumour transplantation. IL-2 therapy of SL2-bearing DBA/2JIco mice resulted in a significant proportion of cures; however, no response to IL-2 treatment was achieved in SL2-bearing DBA/2CrIiw mice. BALB/c mice with the i.p. transplant of M109 responded to IL-2 treatment with 40% increase in lifespan. The low-dose IL-2 therapy of the five spontaneous tumours resulted, in general, in transient growth inhibition of the i.m. transplants of lines X5, X6, and X7 provided that IL-2 was administered locally. The therapeutic effect depended on the number of transplanted tumour cells, the best results being achieved at cell numbers close to the dose-inducing tumour growth in 50% of animals. We found that the spontaneously arising tumours responding to IL-2 treatment were all slowly growing and immunogenic (X6 and X7) or might have viral association (X5) and, as such, might express foreign antigens. The data suggest a correlation between tumour immunogenicity and the therapeutic effect. However, IL-2 can still exert some effect against tumours with negligible immunogenicity. Received: 16 July 1998 / Accepted: 5 October 1998     

Astroglial Knockout of Glucocorticoid Receptor Attenuates Morphine Withdrawal Symptoms,but Not Antinociception and Tolerance in Mice

The development of tolerance and drug dependence limit the clinical application of opioids for the treatment of severe pain. Glucocorticoid receptors (GRs) are among molecular substrates involved in these processes. Most studies focus on the role of neuronal GR, while the involvement of GR on glial cells is not fully understood. To address this issue, we used a transgenic model of conditional GR knockout mice, targeted to connexin 30-expressing astrocytes, treated with repeated doses of morphine. We observed no difference between control mice and astrocytic GR knockouts in the development of antinociceptive tolerance. Nevertheless, when animals were subjected to precipitated withdrawal, knockouts presented some attenuated symptoms, including jumping. Taken together, our data suggest that hippocampal and spinal astrocytic GRs appear to be involved in opioid withdrawal, and drugs targeting the GR may relieve some symptoms of morphine withdrawal without influencing its antinociceptive properties.

     

Rapid screening method for compounds that affect the growth and germination of Candida albicans, using a real-time PCR thermocycler

We propose a screening method for compounds affecting growth and germination in Candida albicans using a real-time PCR thermocycler to quantify green fluorescent protein (GFP) fluorescence. Using P(ACT1)-GFP and P(HWP1)-GFP reporter strains, the effects of a wide range of compounds on growth and hyphal formation were quantitatively assessed within 3 h after inoculation.     

Cytokine Responses to Schistosoma mansoni and Schistosoma haematobium in Relation to Infection in a Co-endemic Focus in Northern Senegal

Background

In Africa, many areas are co-endemic for the two major Schistosoma species, S. mansoni and S. haematobium. Epidemiological studies have suggested that host immunological factors may play an important role in co-endemic areas. As yet, little is known about differences in host immune responses and possible immunological interactions between S. mansoni and S. haematobium in humans. The aim of this study was to analyze host cytokine responses to antigens from either species in a population from a co-endemic focus, and relate these to S. mansoni and S. haematobium infection.

Methodology

Whole blood cytokine responses were investigated in a population in the north of Senegal (n = 200). Blood was stimulated for 72 h with schistosomal egg and adult worm antigens of either Schistosoma species. IL-10, IL-5, IFN-γ, TNF-α, and IL-2 production was determined in culture supernatants. A multivariate (i.e. multi-response) approach was used to allow a joint analysis of all cytokines in relation to Schistosoma infection.

Principal Findings

Schistosoma haematobium egg and worm antigens induced higher cytokine production, suggesting that S. haematobium may be more immunogenic than S. mansoni. However, both infections were strongly associated with similar, modified Th2 cytokine profiles.

Conclusions/Significance

This study is the first to compare S. mansoni and S. haematobium cytokine responses in one population residing in a co-endemic area. These findings are in line with previous epidemiological studies that also suggested S. haematobium egg and worm stages to be more immunogenic than those of S. mansoni.     

Association of primary autoimmune hypothyroidism with Addison's anemia]

Intestinal absorption of vitamin B12 as measured by the Schillin test was studied in 50 patients with primary hypothyroidism of autoimmune origin. The impaired absorption of vitamin B12 was found in 24% of the patients studied, and in 6% a clinically evident form of pernicious anemia was diagnosed. The patients with hypothyroidism and simultaneous defect in absorption of vitamin B12 were characterized by more frequent occurrence of the high titer of antithyroid microsomal antibodies, higher blood serum concentration of TSH and lower blood content of hemoglobin as compared with hypothyroid patients having normal intestinal absorption of vitamin B12.     

Molecular analysis of methicillin-resistant staphylococci isolated from hospital patients and in the out-patient clinic

In this study, a molecular analysis of the methicillin-resistant coagulase-negative staphylococci strains was performed. The obtained results of the biochemical and drug resistant pattern investigations were insufficient to assess the relationship between the strains. Therefore genotyping by the restriction fragment length polymorphism analysis (PCR-RFLP) method was performed. Analyzed strains characterized presence of the mecA gene-PCR products. The PCR products were digested with DraI and TasI, and the fragments separated by agarose gel electrophoresis. Typing of the methicillin-resistant gene using PCR-RFLP showed that all MRCNS strains possess an identical restriction pattern of the mecA gene. This identical restriction pattern of the mecA gene in investigated strains may suggest an easy transfer of this gene between different staphylococci species and lead to the spreading of methicillin-resistant among hospital strains. Furthermore performing the comparison of different phenotype and genotype methods has shown that the PCR-RFLP method is quick and reliable, enabling the detection and estimation of the relationship between MRCNS strains.     

Manganese (III) phthalocyanine-substituted cytochrome c

Manganese phthalocyanine-substituted cytochrome c has been prepared by the reaction of Mn(III) tetrasulfonated phthalocyanine with apocytochrome c in acetate buffer, pH 5.8. Its structure and properties have been investigated by difference spectroscopy, circular dichroism (cd), electron paramagnetic resonance (epr), electrophoresis, molecular weight estimation, and potentiometric measurements. The epr and spectroscopic data show that the manganese phthalocyanine-substituted cytochrome c represents the low spin, six-coordinated. Mn(Ill) complex with the metal ion in the plane of the phthalocyanine ring. The sixth ligand, which is coordinated axially to the metal ion, is probably the methionine-80. Electrophoresis and molecular weight studies show this complex to be a monomer. As is shown by cd experiments, Mn(III)L-apocyt has a more ordered structure than that of apocytochrome c. Its conformation is, however, significantly altered compared to native cytochrome c. The manganese(III)-phthalocyanine complex is able to combine with cyanide. The cyanide derivative gives a stable reduced form upon dithionite reduction. If, however, Mn(IlI)Lapocyt is reduced with dithionite before addition of cyanide, it loses its ability to coordinate with cyanide. Nitric oxide reacts with the manganese(III) complex to form, in all probability, the nitrosyl derivative. The half-reduction potential of Mn(IlI)L-apocyt is about +400 mV, and the complex is reduced by cytochrome c. Spectroscopic data suggest that the mechanism of this process is complicated.     

The CSC proteins FAP61 and FAP251 build the basal substructures of radial spoke 3 in cilia

Dynein motors and regulatory complexes repeat every 96 nm along the length of motile cilia. Each repeat contains three radial spokes, RS1, RS2, and RS3, which transduct signals between the central microtubules and dynein arms. Each radial spoke has a distinct structure, but little is known about the mechanisms of assembly and function of the individual radial spokes. In Chlamydomonas, calmodulin and spoke-associated complex (CSC) is composed of FAP61, FAP91, and FAP251 and has been linked to the base of RS2 and RS3. We show that in Tetrahymena, loss of either FAP61 or FAP251 reduces cell swimming and affects the ciliary waveform and that RS3 is either missing or incomplete, whereas RS1 and RS2 are unaffected. Specifically, FAP251-null cilia lack an arch-like density at the RS3 base, whereas FAP61-null cilia lack an adjacent portion of the RS3 stem region. This suggests that the CSC proteins are crucial for stable and functional assembly of RS3 and that RS3 and the CSC are important for ciliary motility.