Identification of subpopulations of human macrophages through the generation of human macrophage hybridomas.

We have generated a series of human macrophage hybridomas by fusing an HGPRT-deficient promonocytic cell line, U937, with macrophages obtained by allowing monocytes to mature into macrophages in teflon bags. The fusions were documented as true hybrids by the acquisition of donor class I molecules, as well as donor derived macrophage surface antigens. The hybridomas represent clonal expansion of individual macrophages, retaining the surface antigen expression and functional capacity of the normal donor cells including cytokine production and stimulation in a mixed lymphocyte reaction. These cell lines differentially express Vmax antigens found on normal macrophages, potentially identifying subpopulations of macrophages. These lines may be useful not only to study normal macrophage function but may be relevant to a variety of disease states where expansion of subpopulations of macrophages identified by Vmax antigens may be important in disease pathogenesis.

The expression and regulation of class II antigens in normal and inflammatory bowel disease peripheral blood monocytes and intestinal epithelium.

Elevated constitutive expression of major histocompatibility (MHC) class II antigens occurs in the enterocytes of patients with IBD. It has been suggested that this aberrant expression of class II molecules may play a role in the pathogenesis of IBD. We examined two possible reasons for such a finding. 1) Heightened sensitivity of IBD enterocytes to endogenous gamma interferon (gamma IFN) and 2) enhanced endogenous secretion of gamma interferon by intestinal cells in close proximity to the enterocytes (lamina propria lymphocytes). Constitutive and gamma interferon stimulated HLA-DR and DP density on intestinal epithelial cells (IEC) and peripheral blood monocytes (PBM) from UC patients (IEC n = 13; PBM n = 20), CD patients (IEC n = 14; PBM n = 18) and non-IBD controls (IEC n = 12; PBM n = 20) were measured via flow cytometry (mean channel fluorescence). gamma IFN production by PHA stimulated and unstimulated lamina propria lymphocyte (LPL) cultures of UC patients (n = 11) CD patients (n = 8) and non-IBD controls (n = 11) was measured using a vesicular stomatitis virus/WISH cell bioassay. We found significantly greater gamma IFN secretion by IBD-derived PHA stimulated LPL than from non-IBD stimulated controls (CD = 39.4 +/- 12.4u; UC41.5 +/- 6.8u; NL = 22.4 +/- 8.3u, p less than 0.05) while gamma IFN induced HLA-DR and DP upregulation was no greater in IBD-derived IEC and PBM than in non-IBD controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of atopy in an inner-city asthmatic population.

Seventy-three patients at The Mount Sinai Hospital Emergency Room were investigated to determine the prevalence of atopy in asthma in a predominantly black and Hispanic inner-city population. Serum IgE levels and radioallergosorbent tests (RASTs) to eight common inhalant allergens were measured in both the asthmatic group and a nonasthmatic emergency-room control group. The mean total IgE level for the asthma group was 263.8 IU/mL compared to 63.8 IU/mL in the control group (p = 0.032), and 60% of the asthmatics had IgE levels in the atopic range (> 100 IU/mL). Increases in IgE were associated with age under 50 years but did not reach statistical significance. Cockroach, dust mite, cat, and dog were the most common RASTs in the asthmatic group; there were no positive RASTs in the control group. There was a correlation (p = 0.04) between age (less than 50 years) and increased numbers of positive RASTs. These results are similar to those of other studies that have associated atopy with asthma in rural and suburban populations. These data demonstrate that atopy is common in the asthmatic patients seen in The Mount Sinai Hospital Emergency Room and strongly suggest that management of atopic factors should become routine in the care of adult asthmatic patients.

Depression, pain and quality of life in patients with amyotrophic lateral sclerosis: a cross-sectional study.

The complications related to amyotrophic lateral sclerosis (ALS) include pain. A higher risk of depression and a negative effect on quality of life (QoL) might be expected in ALS patients with pain. The aims of this study were to evaluate the prevalence of pain in ALS patients, to compare measures of depression and QoL in patients with and without pain, and to study the influence of depression scores and pain on the QoL of ALS patients with pain. Forty ALS patients were enrolled, and 36 were included in the analysis. Seventy-two percent of patients reported pain. Pain intensity was significantly related to a worsening of QoL (p<.05). This effect was no longer significant after considering depression scores as a covariate. Depression scores significantly decreased QoL (p<.02) and this effect remained significant after considering pain intensity as a covariate (p<.05). Our study suggests that pain is frequent in ALS patients and that depressive symptoms are significantly related to poorer QoL. Clinicians should pay more attention to both pain and depressive symptoms in ALS patients considering their effect on QoL.

The control of class II expression on T cells is independent of the regulation of Tac and the induction of proliferation.

In order to define the association between class II expression and other markers of T cell activation we tested the ability of various modes of stimulation to induce the expression of class II, Tac, and to stimulate proliferation. Stimulation of T cells with phytohaemagglutinin (PHA) in the presence of accessory cells strongly induced proliferation, Tac and the class II antigen DR. When purified T cells without accessory cells were stimulated with the phorbol ester, PdB, and the calcium ionophore, ionomycin, strong proliferation and Tac expression were induced, but only low levels of surface class II were observed. In contrast, stimulation of the same cells with PHA resulted in weak proliferation, strong Tac, but again low class II levels. The addition of PdB to the PHA increased the proliferative response, but did not affect Tac expression, which remained high, or class II expression, which remained low. Subsequent culture in conditioned medium of purified T cells which had been activated with either PdB and ionomycin or with PHA resulted in increased surface class II levels in both cases. Additional experiments suggested that neither IL-2, IL-4, nor interferon-gamma (IFN-gamma) alone was responsible. These results demonstrate that class II expression can be separated from the induction of proliferation and the upregulation of Tac and that the mode of T cell stimulation influences the resulting activation pathway. Furthermore, they suggest that the control of class II expression on T cells is more tightly regulated than it is on other cells.

An endocrinological study of patients with primary cutis verticis gyrata.

An endocrinological study of 15 psychiatric patients with primary cutis verticis gyrata (CVG) and 7 control patients was carried out. The investigation of the pituitary-gonadal axis, pituitary-adrenal axis, pituitary-thyroid axis, prolactin and human growth hormone (basal values and circadian biorhythms) did not show any significant difference between the CVG and the control patients. Only levels of free testosterone were significantly lower in patients with CVG than in the control group (p < 0.05), probably reflecting an increased peripheral use of testosterone.

Abnormal signal transduction by T cells of mice with parental tumors is not seen in mice bearing IL-2-secreting tumors.

There is considerable evidence to demonstrate that immune function is abnormal in tumor-bearing mice, perhaps accounting, at least in part, for progressive tumor growth. In an attempt to generate an antitumor response, we used retroviral vectors to express IL-2 cDNA in CMS5, a murine fibrosarcoma. Mice inoculated with unmodified tumor cells suffered progressive tumor growth, whereas tumors secreting IL-2 were rejected or grew slowly. Animals bearing unmodified but not IL-2-secreting tumors also were immunosuppressed. On the basis of these observations, we were interested in how IL-2 secretion by the tumor cells prevented the onset of hyporesponsiveness. To identify biochemical differences between T cells of mice with parental vs slowly growing IL-2-secreting tumors, we examined signal transduction after activation through the CD3/TCR complex. Protein tyrosine phosphorylation was altered and calcium flux was reduced in cells of mice with parental tumors compared with animals with slowly growing IL-2-secreting tumors. In addition, levels of protein for the tyrosine kinases p56lck and p59fyn, as well as the TCR-zeta-chain, were reduced. These differences in signal transduction were observed for T cells of mice with parental and IL-2-secreting tumors of the same size, demonstrating that differences in tumor size alone could not explain our findings. Thus, IL-2 secretion by tumors seems to be able to prevent immunosuppression by maintaining normal signal transduction in T cells, facilitating the generation of antitumor responses.