Clinical evaluation of 430 MHz microwave hyperthermia system with lens applicator for cancer therapy

The clinical efficacy of a microwave (MW) hyperthermia system using an electric-field converging (lens) applicator is evaluated for 42 malignant tumours with a maximum tumour depth of less than 7 cm. The mean of the maximum, average and minimum tumour temperature of the 42 tumours are 44,5, 42.5 and 40.7 C, respectively. The thermal parameters are higher for tumours in the chest, abdominal walls and hip than for those in the neck, groin and extremities. No apparent difference in thermal parameters according to the depth of tumour is shown. Of 40 tumours treated by hyperthermia in combination with radiotherapy, 20 (50%) showed complete regression, 14 (35%) showed partial regression, and six (15%) showed no change. This phase I and II study indicates clinical feasibility of the newly developed MW heating apparatus, and strongly suggests the usefulness of thermoradiotherapy in the treatment of localised superficial and subsurface malignancies.     

Effect of hepatocyte growth factor on sperm motility

PROBLEM: Hepatocyte growth factor (HGF) exists abundantly in seminal plasma and its receptor, c-met, is expressed on spermatozoa. Considering its motogenic activity, we speculated that HGF might affect the movement ability of spermatozoa. METHODS: Recombinant HGF was added to washed spermatozoa and their movements were analyzed using a computer-assisted sperm analyzer. The concentration of HGF in the seminal plasma of infertile patients (n = 83) was measured by ELISA, and the data were compared with their hormonal profile and semen parameters. RESULTS: The HGF physiological concentration (1 ng/mL) maintained the motility of sperm after a long incubation, though the difference was not statistically significant. Recombinant HGF did not affect the linearity or frequency of movement, which suggested that it does not evoke the hyperactivation of spermatozoa. The concentration of HGF in seminal plasma did not correlate with any clinical parameter of the patients. CONCLUSIONS: These findings contradict the theory that HGF controls the movement of sperm. The main role of this axis in the male reproductive system might be maturation in the epididymis.     

Further development of a recombinant feline herpesvirus type 1 expressing the Gag protein of feline immunodeficiency virus

Summary.  We have previously reported the construction of a recombinant feline herpesvirus type 1 (FHV-1), designated C7301ddlTK-gag, expressing the Gag precursor protein of feline immunodeficiency virus (FIV). In this study, we report the construction of a further recombinant FHV-1 (ddlTK(gBp)-gag) which carries an FHV-1 gB promoter sequence upstream of the FIV gag gene of C7301ddlTK-gag. Strong expression of the FIV Gag protein by ddlTK(gBp)-gag was confirmed by immunoblot analyses and enzyme-linked immunosorbent assays. Although C7301ddlTK-gag and ddlTK(gBp)-gag failed to induce anti-FIV Gag antibodies in cats, we confirmed the infectivity and stability of these recombinants in cats. Received January 14, 2000 Accepted August 4, 2000     

Abnormal distribution of cathepsins in the brain of patients with Alzheimer's disease

Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease.     

Enhancing effects of oral adjuvants on anti-HBs responses induced by hepatitis B vaccine.

Hepatitis B (HB) vaccine is very promising for the prevention of HB infection. There exist, however, some non-responders to current vaccination trials. In this study, taurine, parotin and lithium were selected as adjuvants which can be administered orally. The mechanisms of these three materials as adjuvants and their effects on HB vaccine were investigated in mice. For instance, taurine induced polyclonal antibody production and exhibited adjuvant activity. Although taurine did not have any activity on the proliferation of thymocytes nor stimulate IL-2 production, taurine did induce IL-1 production by macrophages. It was considered that taurine-induced IL-1 would play an essential role in the proliferation and differentiation of B cells. Parotin also induced polyclonal antibody production and exhibited adjuvant activity. These effects of parotin were not affected even if macrophages or T cells were depleted, and parotin itself had an IL-1-like activity. Therefore, it was considered that parotin acted directly on B cells by its IL-1-like activity and mitogenic activity, resulting in the proliferation and differentiation of B cells. Lithium induced neither polyclonal antibody production, nor IL-1 or IL-2 production. However, when given with an antigen, lithium activated the humoral immune system, resulting in the augmentation of antibody production. Oral administration of taurine, parotin and lithium were capable of restoring antibody responses to HB surface antigen (HBsAg) in HBsAg-nonresponder mice. Furthermore, taurine, parotin and lithium enhanced the adjuvant effects of aluminium contained in the present HB vaccine. These observations indicate that use of these oral adjuvants may open new perspectives in the field of human HB vaccination.     

Epitope analysis of HLA-DR-restricted helper T-cell responses to Der p II, a major allergen molecule of Dermatophagoides pteronyssinus

T-cell epitopes of Der p II, a major allergen of Dermatophagoides pteronyssinus , were analyzed by using human T-cell clones. We tested 38 cloned T cells from two Japanese patients with allergic rhinitis, and identified at least two peptides (K33-T47 and 158-C73) as helper T-cell epitopes. The former epitope was shown to be restricted by HLA-DRB1* 1502, and the latter by HLA-DRB1* 0405, both of which are typical Japanese HLA-DR alleles, suggesting that those T-cell epitopes might be important for the onset of house-dust mite allergy in the Japanese population. We prepared 15 analog peptides of the HLA-DRB1* 1502-restricted 15-mer peptide. Of those 15 residues, five (F35, L37, A39, F41, and E42) were critical for the epitope activity, and three residues (F35, A39, and E42) seemed to be included in anchor motifs for HLA-DRB1* 1502. The epitope peptide was also recognized by HLA-DRB1* 1502-positive healthy donors; however, only allergic T cells showed Th2 functions. Antigen-presenting cells of nonallergic donors were able to activate allergic T cells to express Th2 function. This seemed to suggest that antigen recognition of T cells, as well as additional unknown factors which promote Th2, rather than Th1, responses, might be important for the onset of house-dust mite allergy.     

Establishment of efficient reaggregation culture system for gene transfection into immature T cells by retroviral vectors

To overcome low efficiency of retroviral infection into immature T cells, we modified reaggregation fetal thymus organ culture by closely packed co-culture with virus-producing cells (VPC). The viral vector was constructed in chimeric vector, pMX, with IRES and tailless-rat CD2 as a surface marker of infected cells. A rearranged TCR beta gene (Vbeta8.2) was further inserted into the construct for investigating effect of the introduced gene in T cell development. Using this system, we succeeded to transfer the viral vector into immature thymocytes at a remarkably higher efficiency compared to conventional methods using medium containing retrovirus. Moreover, the introduced TCR beta gene was expressed on thymocytes of RAG2-deficient mice to induce in the transition of CD4-CD8- double-negative (DN) into CD4+CD8+ double-positive (DP) cells by transducing beta-selection signaling. Thus, our modified reaggregation culture system is useful for studying the molecular mechanism of T cell development due to a highly efficient gene transfer into immature T cells.