Jean P. Maingay

Interleukin-8 can mediate acute-phase protein production by isolated human hepatocytes

During the course of studies designed to identify the role of cytokines in the reprioritization of hepatic protein synthesis associated with cachexia we detected a hepatocyte-stimulating moiety in the supernatants of pancreatic cancer cells that was unrelated to interleukin (IL)-6. This study identifies that moiety as IL-8 and investigates the role of IL-8 in the induction of acute-phase protein production. The human pancreatic cancer cell line MIA PaCa-2 produced >1 ng/ml of IL-8 per 24 h, and supernatants from this cell line induced C-reactive protein (CRP) production from isolated human hepatocytes. Addition of neutralizing anti-human IL-8 antibody to such supernatants produced almost complete inhibition of CRP production. The addition of recombinant human IL-8 to hepatocytes resulted in a dose-dependent increase in CRP, α1-acid glycoprotein, and α1-antichymotrypsin production and a decrease in the production of transferrin and prealbumin. This study demonstrates that recombinant or tumor-derived IL-8 can modulate acute-phase protein production from isolated human hepatocytes and from human hepatoma cells.During the course of studies designed to identify the role of cytokines in the reprioritization of hepatic protein synthesis associated with cachexia we detected a hepatocyte-stimulating moiety in the supernatants of pancreatic cancer cells that was unrelated to interleukin (IL)-6. This study identifies that moiety as IL-8 and investigates the role of IL-8 in the induction of acute-phase protein production. The human pancreatic cancer cell line MIA PaCa-2 produced >1 ng/ml of IL-8 per 24 h, and supernatants from this cell line induced C-reactive protein (CRP) production from isolated human hepatocytes. Addition of neutralizing anti-human IL-8 antibody to such supernatants produced almost complete inhibition of CRP production. The addition of recombinant human IL-8 to hepatocytes resulted in a dose-dependent increase in CRP, alpha1-acid glycoprotein, and alpha1-antichymotrypsin production and a decrease in the production of transferrin and prealbumin. This study demonstrates that recombinant or tumor-derived IL-8 can modulate acute-phase protein production from isolated human hepatocytes and from human hepatoma cells.

Immune responses to herpes simplex virus in patients with facial herpes simplex and those with eczema herpeticum

The immune response to herpes simplex virus (HSV) was studied in 59 patients with primary and recrudescent facial HSV infections. The patients included nine with atopic eczema, seven of whom had eczema herpeticum (EH). All patients had antibodies to HSV (measured by ELISA) and all but three had HSV‐specific cell mediated immunity (CMI) (measured by in vitro lymphoproliferation). Thirteen control subjects were negative for both tests. All three patients with absent CMI to HSV had suffered from severe EH and had depressed CMI to HSV for several months following an attack. In two of these EH patients, a positive CMI response was produced by in vitro removal of CD8 + ve T lymphocytes from peripheral blood mononuclear cells using a panning technique. Thus the absence of CMI to HSV in these patients was due to suppressor cell function rather than a lack of specifically responsive cells. The other four EH patients with normal CMI to HSV had suffered less severe EH, but no association between the absence of CMI to HSV and serum IgE level or activity of the eczema was apparent in the atopic patients. No specific anti‐HSV IgE antibody was detectable.

A murine model of herpes simplex virus recrudescence.

A murine model is described in which recrudescence of herpes simplex virus (HSV) type 1 was achieved. C3H mice were shaved and irradiated with u.v. B light 3 days before being infected epidermally with a clinical isolate of HSV. Seven weeks or longer following the primary infection, the survivors were again shaved, irradiated with u.v. and mildly tape-stripped. Recrudescent lesions occurred in up to 80% of mice at the site of the original lesion in most cases, but also occasionally at other sites. Skin painting with u.v.-irradiated urocanic acid (a substance suggested to be a photomediator of the immunosuppressive effects of u.v.) in place of u.v.-irradiation induced some recrudescence but was not as efficient as u.v.-irradiation. Antibody titres to HSV had no value in predicting whether recrudescence would occur but lymphoproliferative responses in draining lymph nodes may provide some indication of viral activity at the epidermal site. A hypothesis is developed that u.v.-irradiation before primary infection with HSV induces a suppressive immune response to the virus which affects the virus-host interaction and accounts for a high incidence of recrudescent lesions on subsequent stimulus.

Antigen presentation in patients with recrudescent orofacial herpes simplex virus infections

Recovery from epidermal herpes simplex virus (HSV) infection depends primarily on development of an effective cell‐mediated immune response, possibly generated following antigen (Ag) presentation by epidermal cells (EC). The ability of EC to present HSV Ag was investigated in 12 subjects with occasional recrudescent facial HSV infections. All had circulating HSV specific antibodies and cell‐mediated immunity to the virus. Peripheral blood mononuclear cell suspensions, depleted of antigen presenting cells (APC) by glass adherence and then enriched for T cells by adsorption on nylon wool columns, did not proliferate in response to HSV Ag. Both EC suspensions, prepared from suction blister roofs, and glass‐adherent peripheral blood mononuclear cells (AC) preincubated with ultraviolet‐inactivated HSV, reconstituted the T‐cell proliferative response to HSV. EC were more efficient than AC at presenting HSV Ag to T cells. Depletion of CD1+ cells from EC suspensions by cell sorting reduced their ability to present HSV Ag and augmentation of CD1+ cell numbers supplemented it. Preincubation of EC or AC with monoclonal antibodies to major histocompatibility complex class 11 antigens DP, DQ or DR, blocked the lymphoproliferative response to HSV Ag. Evidence was obtained that cells co‐ordinately expressing products of the DP, DQ and DR loci are involved in presentation of HSV Ag by both EC and AC.

Studies of three canine mammary carcinoma cell lines—I. In vitro properties

Three cells lines, REM 134, 111 and 367, have been derived from canine mammary carcinomas and their morphological characteristics in vitro are described. They are tumorigenic in athymic nude mice, have no demonstrable fibronectin on their cell surfaces and exhibit a varied pattern of lectin binding. They can be cloned in semi-solid agar. One line, REM 134, responds to oestrogen and luteotropic hormone in vitro, although none of the three had demonstrable oestrogen receptors.

Interactions between herpes simplex virus and murine bone marrow macrophages

SummaryMacrophages from murine bone marrow (strain C3Hf Bu/Kam) were culturedin vitro in L-cell conditioned medium. After 0, 2, 4, 6, 8 and 10 days, they were infected with a clinical strain of herpes simplex virus type 1 and the outcome followed morphologically, by phagocytic index, infectious virus yields, immunofluorescence, expression of Fc receptors and major histocompatibility complex (MHC) Class II antigens. At a multiplicity of infection of 1–5, little morphological difference was apparent between infected and uninfected cultures at early stagesin vitro but marked changes occurred later with reduction in cell numbers in the infected cultures. Indirect immunofluorescence failed to detect cells expressing early viral antigens, and yields of infectious virus indicated that permissive infection was not taking place. While phagocytic index and Fc receptor expression did not change 24 hours post-infection, MHC Class II antigen expression was increased. Thus, although the bone marrow macrophages seem predominantly resistant to infection with HSV-1, they may be modified by the presence of the virus. Since macrophages may act as antigen presenting cells for the immune system, this type of mechanism may be important in the generation of local immune responses.

Studies of three canine mammary cell lines—II. In Vivo properties

Three cell lines, REM 134, 111 and 367, derived from canine mammary carcinomas have been used to induce tumours in athymic nude mice after subcutaneous injection. The histopathology of the tumours was compared and each was found to resemble closely the original tumour. This did not change after serial in vivo passage. Metastasis never occurred. Injection of REM 134 cells intracranially resulted in a fast-growing tumour which also did not metastasize; injection intrapleurally resulted in growths most commonly on the mediastinum with confinement to the chest cavity. Fibronectin was present in the subcutaneous tumours. Two of the cell lines were cloned in semi-solid agar. When tested, these clones induced tumours identical histologically to the uncloned ones. Finally, male and female mice were injected subcutaneously with the same number of cells from each of the three lines but the rate of tumour growth did not differ significantly between the two sexes.