Further investigation of the HEXA gene intron 9 donor splice site mutation frequently found in non-Jewish Tay-Sachs disease patients from the British Isles.

In a previous study we found that a Tay-Sachs disease (TSD) causing mutation in the intron 9 donor splice site of the HEXA gene occurs at high frequency in non-Jewish patients and carriers from the British Isles. It was found more frequently in subjects of Irish, Scottish, and Welsh origin compared with English origin (63% and 31% respectively). We have now tested, in a blind study, 26 American TSD carriers and 28 non-carriers who have British ancestry for the intron 9 splice site mutation. Six of the carriers and none of the controls were positive for the mutation. All six had Irish ancestry, compared with nine of the 20 other (intron 9 mutation negative) TSD carriers (p < 0.05). These results confirm the previously found high frequency of the intron 9 mutation in non-Jewish TSD families of British Isles, particularly Irish, origin, and reinforce the need to screen such families for this mutation.     

Induction of immune responses in patients with B-cell lymphoma against the surface-immunoglobulin idiotype expressed by their tumors.

BACKGROUND. The idiotypic determinants of the surface immunoglobulin of a B-cell lymphoma can serve as a clonal tumor-specific marker, which may have implications for immunotherapy. We sought to determine whether idiotype-specific immune responses against this autologous antigen could be induced in patients with B-cell lymphoma. METHODS. Nine patients were selected who had minimal residual disease or a complete remission after chemotherapy. Each received a series of subcutaneous injections of the immunoglobulin derived from his or her tumor cells (immunoglobulin-idiotype protein), which had been conjugated to a protein carrier and mixed with an immunologic adjuvant. RESULTS. In seven of the nine patients the injections induced sustained idiotype-specific immunologic responses of the humoral type (two patients), the cell-mediated type (four patients), or both (one patient). The use of an adjuvant was essential for these immune responses. The induced antibodies bound specifically to autologous immunoglobulin idiotype, inhibited the binding of murine monoclonal antiidiotype antibodies, and bound autologous tumor cells. Cell-mediated responses were demonstrated by the specific proliferation of immune peripheral-blood mononuclear cells to the soluble immunoglobulin-idiotype protein in vitro. The tumors of both of the patients with measurable disease regressed completely. Toxicity associated with the vaccine was minimal and consisted only of mild reactions at the site of intramuscular injection. CONCLUSIONS. These results demonstrate that autologous immunoglobulin idiotype can be formulated into an immunogenic, tumor-specific antigen in humans with B-cell lymphoma, and they provide the background for large-scale trials of active specific immunotherapy of this disease.     

Diversity of T-cell antigen receptor variable genes used by mycosis fungoides cells.

The expression of T-cell antigen receptor beta-chain variable genes (V beta) was evaluated in 28 cases of mycosis fungoides. A novel polymerase chain reaction (PCR) technique was used to associate expression of particular V beta genes with monoclonal T-cell populations. In addition, the same biopsies used for PCR analysis were also examined for reactivity with a panel of seven monoclonal antibodies that specifically recognized V beta proteins from four different families. Only three cases clearly stained with the antibodies, a result consistent with a diverse set of V beta genes being used. This was confirmed by PCR analysis, which indicated that V beta genes from many different families were expressed by these tumors. Preferential use of the V beta 8 family, which had been previously use of the V beta 8 family, which had been previously reported for this disease, was not evident among the cases analyzed.     

A study of bereavement in general practice

Forty six bereaved relatives were assessed by a general practitioner four to eight weeks after the bereavement. In 36 (78·3 per cent) the immediate reaction to bereavement was one of numbness or stupefaction; in seven (15·2 per cent) emotional relief occurred; and in three cases (6·5 per cent) there was no obvious immediate reaction. The numbness reaction was limited in duration to a week or less in 31 of the 36 instances.

At four to eight weeks after bereavement 29 (63·0 per cent) of the subjects continued to experience difficulty in coming to terms with their loss. Twenty subjects reported guilt feelings and a similar number expressed aggressive reactions. The bereaved subjects tended to increase their consumption of cigarettes and alcohol, while their appetite and weight tended to be reduced. Thirty six (78·3 per cent) of the subjects reported physical symptoms, notably headache, dizziness, generalised aches, and abdominal complaints.

The most prominent psychological features of bereavement were found to be: preoccupation with thoughts of the deceased, idealisation of the lost person, depressive mood, and loneliness.

The findings are discussed and reference made to the role of the family doctor in the management of bereavement reactions.

     

Total opening valves for a ventricular prosthesis

Ventricular prosthesis used in assistance and cardiac substitution must have valves with characteristics different from classic valve prosthesis. In particular, valve leakage flow and its closing period must be reduced. The authors compare the characteristics of usual artificial valves and propose a new total opening valve with leaflets, which answers the requirements as well as possible.     

Effect of pulse dose cyclophosphamide on the anamnestic immune response in NZB/W mice

Mice exhibiting a spontaneous SLE-like lethal autoimmunity (female NZB/W hybrids) were given monthy doses of cyclophosphamide (CPA) 240 mg/kg p.o. starting at four months of age. Antibodies to DNA and sheep red blood cells (SRBC) were measured as well as general well being of the mice. The CPA-treated group demonstrated a marked increased in survival compared to the untreated controls with reduction of anti-DNA antibody levels but only a slight inhibition of the anamnestic response to SRBC immunization.Supported in part by USPHS Grant No. GM 15759.     

Expression of human CD81 in transgenic mice does not confer susceptibility to hepatitis C virus infection

We previously demonstrated that hepatitis C virus (HCV) binds to human CD81 through the E2 glycoprotein. Therefore, expression of the human CD81 molecule in transgenic mice was expected to provide a new tool to study HCV infection in vivo, as the chimpanzee is the only species currently available as a laboratory animal model that can be infected with HCV. We produced transgenic mice expressing the human CD81 protein in a wide variety of tissues. We confirmed binding of recombinant E2 glycoprotein to the liver tissue as well as to thymocytes and splenic lymphocytes in the transgenic mice. We inoculated chimpanzee plasma infected with HCV into these animals. None of these transgenic animals showed evidence of viral replication. Furthermore, human CD81 transgenic mice that lack expression of endogenous mouse CD81 were also resistant to HCV infection. We conclude that expression of human CD81 alone is insufficient to confer susceptibility to HCV infection in the mouse. The presence of additional possible factors for HCV infection is discussed.     

Fgl2 prothrombinase expression in mouse trophoblast and decidua triggers abortion but may be countered by OX-2

Spontaneous abortion of normal karyotype embryos in mice and in humans is associated with an increase in uterine T helper (Th) 1 type proinflammatory cytokines, tumour necrosis factor (TNF)-alpha, interferon-gamma and interleukin (IL)-1, and a deficiency of Th2/3 type cytokines, IL-4, IL-10, and transforming growth factor (TGF)-beta2. In mice, Th1 cytokines up-regulate a novel prothrombinase, fgl2, which via thrombin, leads to activation of polymorphonuclear leukocytes that terminate the pregnancy. Here we show that Th1 cytokines up-regulate fgl2 mRNA in fetal trophoblast and secondary decidua of CBA/JxDBA/2 and CBA/JxBALB/c matings, and promote fibrin deposition. This pattern is accompanied by a high rate of abortion. However, the spontaneous abortion rates in abortion-prone CBAxDBA/2 matings and in low abortion rate CBAxBALB/c matings were significantly lower than that expected from the frequency of implantations with high levels of fibrin and fgl2 mRNA(hi). As the glycoprotein OX-2 occurs in the pregnant rat uterus and can deviate cytokine responses to Th2/3, we investigated OX-2 in pregnant CBA/J mice. We found OX-2 mRNA was present at the same sites as fgl2 mRNA, but was reduced in response to Th1 cytokines. Furthermore, anti-OX-2 raised the abortion rate to predicted levels, while recombinant OX-2 dramatically reduced the abortion rate. Fgl2 prothrombinase may provide a mechanism explaining pregnancy loss, and conversely, successful pregnancy may be due in part to OX-2-dependent activation of maternal tolerance mechanisms at the feto-maternal interface.