HLA-DR Antigen Expression Research Articles

Analysis of T cell subsets and beta chemokines in patients with pulmonary sarcoidosis.

BACKGROUND: Sarcoidosis is a systemic granulomatous disorder of unknown origin characterised by accumulation of T lymphocytes and macrophages in multiple organs. Several cytokines and adhesion molecules may contribute to the...

Hepatic overexpression of MHC Class II antigens and macrophage-associated antigens (CD68) in patients with biliary atresia of poor prognosis

The pathogenesis of biliary atresia (BA) is still unknown. Progression to cirrhosis despite restoration of bile flow by successful portoenterostomy suggests that it is a progressive disease of the liver and biliary tree. Whether immunologic factors play any role in the development of this disease remains uncertain. Aberrant expression of major histocompatibility complex (MHC) Class II antigens of HLA-DR on hepatocytes and biliary epithelium is regarded as important in the progression of hepatocellular and biliary damage mediated by cytotoxic T cells. This study was undertaken to evaluate expression of MHC Class II antigen and macrophage-associated antigens (CD68) in liver of patients with biliary atresia to determine their prognostic usefulness and possible role in the pathogenesis of the disease. Liver biopsy specimens from infants with BA (n = 15), neonatal hepatitis (n = 3), and normal livers (n = 6) were studied using an indirect immunoperoxidase staining using antibodies against MHC Class II antigen and macrophage-associated antigens (CD68) as well as routine H&E and Masson's trichome stain. In patients with biliary atresia, the liver biopsy specimen was obtained at the time of Kasai portoenterostomy. Expression of HLA-DR antigens and CD68 antigens was either absent or minimal in normal liver biopsy specimens. There were a few HLA-DR antigens and a few CD68-positive cells around portal tracts in all patients with neonatal hepatitis and five of the seven biliary atresia patients with successful Kasai portoenterostomy. In contrast, there was strong expression of HLA-DR antigen in bile ductules, inflammatory cells, and adjacent damaged hepatocytes and marked CD68-positive macrophage infiltrate in the portal tracts as well as hepatic lobules in two patients with good prognosis and in all eight patients with bad prognosis. Hepatic expression of MHC Class II antigen and CD68 antigens correlated well with the severity of clinical course in patients with BA and may act as a prognostic factor in these patients.

Interleukin-10. A role in the development of postoperative immunosuppression.

The cause of diminished monocyte major histocompatibility complex class II antigen expression after surgery or trauma is unclear. Interleukin-10 (IL-10) regulates inflammatory cytokine production and major histocompatibility complex class II (HLA-DR) expression in vitro. To quantify in vivo IL-10 messenger RNA (mRNA) and protein and monocyte HLA-DR expression after major surgery and to investigate the effects of IL-10 neutralizing blockade on monocyte HLA-DR expression in vitro. Inception cohort study of 48 surgical patients from preoperative status to postoperative day 7 and 9 healthy volunteers (controls). Large teaching hospital, Northern England. Monocyte HLA-DR and cytokine mRNA expression was determined in 32 of 48 consecutive patients undergoing elective major resectional surgery. Mononuclear cells for in vitro studies and serum samples for IL-10 measurement were obtained from the remaining 16 patients. Monocyte HLA-DR expression determined by flow cytometry, IL-10, and tumor necrosis factor mRNA in peripheral blood mononuclear cells assayed by multiplex reverse transcriptase polymerase chain reaction, and serum IL-10 determined by enzyme-linked immunosorbent assay. Monocyte HLA-DR expression (in mean channel fluorescence units [MCF]) was significantly reduced 24 hours after surgery (MCF [+/- SEM], 32.6 +/- 2.3 vs 16.3 +/- 1.2; P < .001) and remained low during the first postoperative week. A relative increase in IL-10 to G3PDH mRNA ratio (mean [+/- SEM], 0.95 +/- 0.08 vs 0.59 +/- 0.06; P < .01) and serum IL-10 (mean [+/- SEM], 18.1 +/- 4.1 vs 5.4 +/- 0.8 pg/mL; P < .01) was noted on the first postoperative day. A significant correlation existed between HLA-DR antigen expression and the presence of IL-10 mRNA transcript on the first postoperative day (P < .01). Lipopolysaccharide-induced up-regulation of monocyte HLA-DR expression was significantly impaired on the first postoperative day (mean [+/- SEM], 151% +/- 24.4% vs 60% +/- 10.1%; P < .01), but this was partially reversed by IL-10 neutralizing antibody (mean [+/- SEM], 60% +/- 10.1% vs 115% +/- 11.6%; P < .01). Interleukin-10 gene expression correlates with the fall in monocyte HLA-DR antigen expression in patients undergoing major abdominal surgery and may account for the immunosuppression associated with surgical injury.

Acute T-cell activation is detectable in unstable angina.

Recent studies suggest a role for inflammation in the pathophysiology of unstable angina. This study was designed to investigate whether circulating lymphocytes are involved in the inflammatory reaction associated with the episodes of unstable angina. Twenty-nine patients with proven unstable angina, 36 with stable angina, and 30 healthy subjects were studied. Both early and short-lived (interleukin-2 receptor [IL-2R], alpha-chain CD25, and transferrin receptor CD71) and late antigen (HLA-DR) expression were investigated by flow cytometric analysis. Soluble IL-2R (sIL-2R) was also measured in plasma by ELISA. Lymphocyte activation was studied at day 1 of hospital admission and after 7, 15, 30, 60, and 90 days. In patients with unstable angina, the number of HLA-DR+ CD3 lymphocytes and levels of sIL-2R were higher (P < .001) than in patients with stable angina and control subjects. Both CD4+ and CD8+ lymphocytes expressed HLA-DR antigens. No differences were found among the different groups of subjects in regard to the expression of CD25 and CD71. Lymphocyte activation was more marked in patients with urgent revascularization. No relationships were found between the number of HLA-DR+ lymphocytes and either the severity of coronary angiographic lesions or the number of ischemic episodes. Observations over time showed a gradual decrease in the number of HLA-DR+ lymphocytes and sIL-2R levels from weeks 3 through 8 to 12. The present results indicate that (1) CD4+ and CD8+ circulating lymphocytes are activated in patients with unstable angina, and their activation state lasts 6 to 8 weeks; and (2) activation of lymphocytes is not a consequence of myocardial ischemia. These results support the immune system-mediated inflammatory nature of unstable angina.

Quantitative alterations of the functionally distinct subsets of CD4 and CD8 T lymphocytes in asymptomatic HIV infection: changes in the expression of CD45RO, CD45RA, CD11b, CD38, HLA-DR, and CD25 antigens.

We determined the representation in asymptomatic human immunodeficiency virus (HIV) infection of the CD45RO+ and CD45RO- CD45RA+ subsets of CD4+ and CD8+ T lymphocytes, CD11b+ and CD11b- subsets of CD8+ T cells, and activated populations of these subsets. Three-color flow cytometry was used to quantitate the different CD4+ and CD8+ T cell populations in 116 asymptomatic HIV+ individuals. In asymptomatic HIV+ infection there was a significant relative increase in the CD4+ CD45RO+ and CD8+ CD45RO+ T cell subsets, which express CD38 and DR antigens, that correlated strongly with the decline in total CD4+ T cells. In addition, we found a loss of CD4+ CD45RO- and CD8+ CD45RO- T cells associated with progression of HIV infection (as measured by the decline in total CD4+ T cells). Studies presented here also indicate that, with the progression of asymptomatic HIV infection, CD8+ CD11b- T lymphocytes showed a significant decrease, whereas CD8+ CD11b+ T cells were significantly increased. This study demonstrates that the progression of HIV infection in asymptomatic patients involves the increase in CD45RO+ subsets of CD4+ and CD8+ T cells, the increase in CD8+ CD11b+ T cells, the decrease in CD45RO- CD45RA+ subsets of CD4 and CD8 T cells, and the decline in CD8+ CD11b- T cells.

口腔へん平上皮癌におけるＨＬＡ‐ＤＲ抗原発現の免疫組織化学的検討 とくにＳｔａｇｅ Ｉ，ＩＩ症例について

本研究の目的は, 口腔扁平上皮癌Stage I, II症例の80例を対象に, HLA-DR抗原の発現およびTリンパ球浸潤を免疫組織化学的に検索し, 腫瘍の局所免疫応答について検討することとした。結果1.口腔扁平上皮癌におけるHLA-DR抗原の発現は80例中21例 (26%) に認められた。2.原発部位では舌にHLA-DR抗原の発現例が最も多かった。3.高分化型が中等度分化型に比較し, 有意にHLA-DR抗原の発現例が多かった。4.腫瘍の浸潤傾向が強いほどHLA-DR抗原の発現頻度が低下していた。5.腫瘍組織内Tリンパ球の浸潤度が強いほどHLA-DR抗原の発現例が有意に多くなっていた。6.HLA-DR抗原の発現例では, 5年生存率が高くなっていたが, 再発, 頸部後発リンパ節転移との明らかな関連性は認められなかった。7.口腔扁平上皮癌の腫瘍細胞におけるHLA-DR抗原の発現が, 宿主の局所免疫応答に関与している可能性が示唆された。

Selective IL-10 inhibition of HLA-DR expression in IFN-?-stimulated human retinal pigment epithelial cells

PURPOSE. Human RPE cells express HLA-DR antigens, bind leukocytes via ICAM-1, and secrete IL-8 and MCP-1, which attract and activate leukocytes. Since little is known concerning endogenous cytokines that may alter ocular immunologic and inflammatory mechanisms, we investigated whether IL-10, an immunosuppressive cytokine, modulates these HRPE features. METHODS. IL-10 effects on HLA-DR and ICAM-1 were examined by HRPE exposures to: (1) IFN-? (10–1000 U/ml) + IL-10 (1–100 U/ml) and (2) IL-10 pre-incubation followed by IFN-? + IL-10. Immunohistochemistry for HLA-DR and ICAM-1 was graded by masked observers. Flow cytometric analysis quantitated HRPE HLA-DR and ICAM-1. Effects of IL-10 on IL-1ß (0.2 or 2 ng/ml)-, or TNF-a (0.2 or 2 ng/ml)-induced IL-8 and MCP-1 secretion and gene expression were assessed using enzyme-linked immunosorbent assay (ELISA) and Northern blot analysis. RESULTS. HLA-DR expression, detected by immunohistochemistry and flow cytometric analysis, showed dose-dependent increases to IFN-?. IL-10 pre-/co-incubation, but not co-incubation alone, markedly reduced HLA-DR expression, but did not modulate constitutive or IFN-?-induced ICAM-1. IL-10 alone did not induce MCP-1 or IL-8 secretion or steady-state mRNA expression, nor modulate IL-1ß-, TNF-a- or IFN-?-induced IL-8 or MCP-1. CONCLUSIONS. This study suggests that HRPE HLA-DR antigens are selectively inhibited by IL-10, but the timing of IL-10 exposure may be crucial.

Comparison of phenotypic and functional properties of immediately ex vivo and cultured human adult microglia

Microglial cells are resident cells of the CNS and are implicated as regulators and effectors of immune responses which occur within this compartment. The precise role of parenchymal microglia remains speculative because distinctions between these cells, perivascular “microglia,” and blood-derived monocytes/macrophages are not well defined. The current study describes the phenotype and function of microglia immediately upon isolation from the non-inflamed adult human CNS and the phenotypic changes which occur in these cells when maintained in tissue culture. We find that the characteristic phenotype of immediately ex vivo parenchymal microglia (CD11c-/CD45low/CD14-) corresponds to that found in situ in the “normal” human brain. The phenotype differs from that of perivascular “microglia” in situ and PBDM (both CD45hi/CD14++). The immediately ex vivo microglia express B7-2 and HLA class II molecules and can support alloantigen-induced proliferation by CD4+ T cells freshly isolated from peripheral blood. Following in vitro culture, the cells are characterized by a bipolar morphology, continued lower levels of CD45 expression compared to PBDM, and slight upregulation of B7-1 and HLA-DR antigen expression. CD14 becomes expressed at high levels on the cells, suggesting that CD14 can serve as an apparent marker of microglia activation which is not based on changes in morphology or APC capacity. Further, treatment of the cells with IFN-γ and LPS causes further upregulation of HLA-DR and clear expression of B7-1 molecules on the surface. The capacity to characterize phenotypic and functional properties of microglia before and after activation provides an opportunity to determine means to manipulate the immune regulatory and effector properties of this cell type. © 1996 Wiley-Liss, Inc.

Interleukin-7 (IL-7) Induces Retinal Pigment Epithelial Cell MCP-1 and IL-8

The neuroectodermally-derived retinal pigment epithelium (RPE) forms part of the blood–retina barrier where it is strategically-positioned to regulate leukocyte infiltration in retinal diseases. Activated human RPE cells possess several functions enabling them to perform this role including expression of HLA-DR antigens, production of intercellular adhesion molecule-1, and secretion of monocyte chemotactic protein-1 and interleukin-8. In this study, we examined the ability of interleukin-7 to induce RPE-derived monocyte chemotactic protein-1 and interleukin-8 and assessed the potentiating effects of interleukin-7 on interleukin-1β- and tumor necrosis factor-α-induced RPE monocyte chemotactic protein-1 and interleukin-8 production. Human RPE cells incubated with interleukin-7 (1–100 ng ml −1) for 24 hr secreted significant levels of antigenic RPE monocyte chemotactic protein-1 and interleukin-8 in a dose-dependent fashion interleukin-7 ( P<0.05). RPE costimulation with interleukin-7 and interleukin-1β (2 ng ml −1) or tumor necrosis factor-α(2 ng ml −1) resulted in additive increases ( P<0.05) in secreted monocyte chemotactic protein-1 and interleukin-8. Steady-state RPE monocyte chemotactic protein-1 mRNA was substantially increased by interleukin-7 (1–100 ng ml −1), while RPE interleukin-8 mRNA was mildly elevated by higher doses of interleukin-7 (10–100 ng ml −1). Time-dependent increases in RPE monocyte chemotactic protein-1 and interleukin-8 mRNA were noted. RPE monocyte chemotactic protein-1 mRNA peaked at 2 hr and decreased over 8 hr and 24 hr. Whereas, RPE interleukin-8 mRNA was perceptible at 2 hr, maximal at 8 hr, and reduced by 24 hr. Interleukin-7 potentiated interleukin-1β-induced monocyte chemotactic protein-1 and interleukin-8 steady-state mRNA expression at all interleukin-7 concentrations. Interleukin-7 potentiated tumor necrosis factor-α-induced RPE monocyte chemotactic protein-1 steady-state mRNA expression at all doses of interleukin-7 while only high dose interleukin-7 (100 ng ml −1) enhanced tumor necrosis factor-α-induced RPE interleukin-8 steady-state gene expression. Our data show that interleukin-7 is a primary stimulus of RPE monocyte chemotactic protein-1 and interleukin-8. This is one of the first reports demonstrating: (1) interleukin-7 induction of monocyte chemotactic protein-1 in any cell type, and (2) interleukin-7 induction of interleukin-8 in resident, tissue-based cells. These studies suggest that interleukin-7 potentiation of interleukin-1βand tumor necrosis factor-α-induced RPE monocyte chemotactic protein-1 and IL-8 may be important for the elicitation of leukocyte chemotaxins in diseased retinal tissue when only low ambient levels of individual pro-inflammatory cytokines are present.

A comparison of glandular involvement between chronic graft-versus-host disease and Sjögren's syndrome

Patients with chronic graft-versus-host disease (cGVHD) occasionally suffer from symptoms of xerostomia and xerophthalmia, which are also features of Sjögren's syndrome (SS). To identify differences in the glandular involvement between cGVHD and SS, we measured the proportions of infiltrating lymphocyte subsets and the expression of HLA-DR antigen and cell adhesion molecules in labial salivary glands (LSG). In cGVHD, more than 90% of the infiltrating lymphocytes were T cells with a slight predominance of CD8 + over CD4 + cells. In SS, CD4 + cells were predominant, and B cells accounted for 10–30% of the infiltrating lymphocytes. Ductal epithelial cells associated with lymphocytic infiltration expressed HLA-DR antigen in both cGVHD and SS. In SS alone, HLA-DR antigen expression also occurred without associated lymphocytic infiltration. The expression of adhesion molecules on ductal epithelial cells, especially vascular cell adhesion molecule-1, was more intense in SS than in cGVHD, while that on endothelial cells was similar in cGVHD and SS. These data suggest that the pathogenesis of glandular involvement of cGVHD is different from that of SS.

Increase of HLA-DR-positive natural killer cells in peripheral blood from patients with IgA nephropathy

Previous in vivo and in vitro studies have presented various abnormalities of cellular immunity in patients with IgA nephropathy (IgAN). In the present study, we describe increased expression of HLA-DR antigens on peripheral natural killer cells (NK cells) in relation to altered cytokine interactions. The numbers of HLA-DR expressing NK cells were enumerated by twocolor flow cytometry and found to be significantly increased in patients with IgAN. Peripheral blood mononuclear cells were then fractionated into pure NK cells by a magnetic cell-sorting system and analyzed concerning expression of messages of interleukin (IL)-2, IL-4, tumor necrosis factor (TNF)-α, and Interferon (IFN)-γ by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). Among the four cytokines, only the IFN-γ message was significantly increased in patients' NK cells. Furthermore, intensity of the IFN-γ message in NK cells showed positive correlation with the percentage of HLA-DR-positive NK cells from the same patient. Then we assayed serum levels of IL-2, IL-12, and IFN-γ by enzyme-linked immunosorbent assay (ELISA) and the levels of IL-12 and IFN-γ showed positive correlations with HLA-DR expression on NK cells. Creatinine clearance of the patients was reevaluated 36 months later, and patients with high HLA-DR on NK cells tended to show faster deterioration of renal function than patients with lower HLA-DR expression. On the basis of these findings, we suggested that HLA-DR-positive NK cells in patients with IgAN form an “activated” population that produces IFN-γ, and this unique cell population may be maintained by multiple factors and be involved in the development and progression of IgAN.

K-ras mutations and HLA-DR expression in large bowel adenomas.

A total of 72 sporadic colorectal adenomas in 56 patients were studied for the presence of point mutations in codons 12 and 13 of the K-ras gene and for HLA-DR antigen expression related to clinicopathological variables. Forty K-ras mutations in 39 adenomas were found (54%): 31 (77%) in codon 12 and nine (23%) in codon 13. There was a strong relationship between the incidence of K-ras mutations and adenoma type, degree of dysplasia and sex. The highest frequency of K-ras mutations was seen in large adenomas of the villous type with high-grade dysplasia. Fourteen out of 15 adenomas obtained from 14 women above 65 years of age carried mutations. HLA-DR positivity was found in 38% of the adenomas, large tumours and those with high-grade dysplasia having the strongest staining. Coexpression of K-ras mutations and HLA-DR was found significantly more frequently in large and highly dysplastic adenomas, although two-way analysis of variance showing size and grade of dysplasia to be the most important variable. None of the adenomas with low-grade dysplasia showed both K-ras mutation and HLA-DR positivity (P = 0.004). K-ras mutation is recognised as an early event in colorectal carcinogenesis. The mutation might give rise to peptides that may be presented on the tumour cell surface by class II molecules, and thereby induce immune responses against neoplastic cells.

HLA antigen expression in enteropathy associated T cell lymphoma.

To investigate the occurrence of abnormal patterns of HLA-ABC and HLA-DR expression in enteropathy associated T cell lymphoma and to relate such abnormalities to the Epstein Barr virus (EBV) status of the tumours. Eleven enteropathy associated T cell lymphomas were immunostained with HC10 (HLA-ABC heavy chain) and TAL 1B5 (HLA-DR alpha chain) monoclonal antibodies and polyclonal anti-beta 2 microglobulin (beta 2m, the HLA-ABC light chain) antibodies. In situ hybridisation for EBV using EBER probes was performed on all cases. Tumour cells of two of 11 patients were EBER positive. One of these showed partial, and the other, complete loss of beta 2m. HLA-DR expression was undetectable in both patients. Of the remaining nine EBER negative tumours, two were HLA-ABC heavy chain negative or showed only occasional positive cells and five of nine showed partial or complete loss of the HLA-ABC light chain, beta 2m. Seven of the nine cases were either negative for HLA-DR or showed weak expression in a proportion of tumour cells. These data show that low or absent HLA-ABC and HLA-DR antigen expression occurs commonly in enteropathy associated T cell lymphoma. These abnormal patterns of HLA expression may be associated with escape from immune attack which, in a minority of patients, could be directed against EBV antigens.

The immunopathogenesis of retroviral diseases: No immunophenotypic alterations in T, B, and NK cell subsets in SIVmac239‐challenged rhesus macaques protected by SIVΔnef vaccination

Immunophenotype analysis was used to characterize circulating lymphocyte subset levels in both rhesus monkeys that were chronically infected with SIVmac239 and in those that had resisted SIVmac239 infection as a result of prior vaccination with an attenuated SIV strain. Alterations in T, NK, and B cell subsets were compared with those previously identified in humans chronically infected with HIV [8-11, 14, 22]. The well-known decrease in CD4+ cell levels was observed in the SIVmac239-infected animals. However, these animals had relatively little activation of circulating CD8+ T cells as compared with uninfected monkeys. This contrasts with chronically HIV-infected humans who have substantial activation of circulating CD8+ cells as evidenced by elevated HLA-DR and CD38 antigen expression on CD8+ cells as well as substantially increased percentages and numbers of total CD8+ cells. NK cells of the SIVmac239-infected animals, on the other hand, demonstrated the same changes recently described in HIV-infected humans, i.e., a decrease in circulating percentages and a decreased amount of FcRIII (CD16). B cell percentages were markedly increased in the SIVmac239-infected animals, a finding also noted in some children with HIV infection but not in HIV-infected adults. SIV delta nef-vaccinated/SIVmac239-challenged animals showed none of the immune alterations found in the SIVmac239-infected monkeys, providing further confirmation of lack of SIV disease in these vaccinated animals.

Effects of interferon-alpha, beta, and gamma on the function of differentiated leukemic HL-60 cells induced by 1,25-dihydroxyvitamin D3.

The differentiation of HL-60, a human leukemic cell line, into monocyte-like cells (D3-HL-60 cells) is induced by 1,25-dihydroxyvitamin D3 (D3). We examined the effects of interferon (IFN) treatment of D3-HL-60 cells on the expression of cell surface antigens, the phagocytic activity for fluorescent beads, production of oxygen radicals, and intracellular growth of Legionella pneumophila. Activation of D3-HL-60 cells with IFN-gamma, Beta, and alpha for 24 h significantly increased expression of CD16, CD36, CD71, and HLA-DR antigens. IFN-gamma markedly enhanced the phagocytic activity of beads in D3-HL-60 cells. There was no significant difference in phagocytic activity between cells exposed to IFN-alpha or beta and untreated D3-HL-60 cells. IFN-alpha, beta, and gamma enhanced production of oxygen radicals, including superoxide, by D3-HL-60 cells. Superoxide production was enhanced to the greatest degree by IFN-gamma, followed by IFN-beta and then IFN-gamma. Intracellular growth of L. pneumophila in D3-HL-60 cells was inhibited by interferons (IFN-gamma > beta > gamma). Similar results were obtained in human mononuclear cells. These data indicate that interferons can act as biologic response modifiers not only in human mononuclear cells but also in differentiated leukemic cells. Our results may have implications for the development of differentiation therapy for treatment of leukemia.

Differences of reactivity to interferon gamma in HeLa and CaSki cells: a combined immunocytochemical and flow-cytometric study.

We characterized the changes induced by treatment for 48 h with 100 U/ ml interferon gamma (IFN-gamma) on HeLa and CaSki cells, derived from human uterine carcinomas and containing human papillomavirus (HPV) type 16 and HPV type 18 respectively, by studying cell growth, cell morphology, the cell cycle and expression of epidermal growth factor (EGF) receptor, filaggrin-profilaggrin and MHC class II antigen, HLA-DR. The response of the two cell lines to IFN gamma differed in some cases. In both cell lines, the cells remained viable; cell growth was similarly inhibited as shown by cell counts. Signs of morphological changes were essentially observed in HeLa cells. The cell cycle phases, analyzed by flow cytometry were more disturbed in CaSki than in HeLa cells; the proportion of CaSki cells in S phase increased and those in G2 + M decreased. Expression of EGF receptors related to proliferation increased only in CaSki cells while expression of filaggrin-profilaggrin, a marker of differentiation, and HLA-DR, a marker of epithelial cell immune response, was enhanced in both cell lines. The presence of filaggrin-profilaggrin being unexpected in these cells, the specificity of the reaction with the monoclonal antibody AKH1 was confirmed by immunoblotting. In conclusion, our results show that the two cell lines reacted differently to IFN gamma although they are of similar origin and the different antigens studied may be useful to predict the progression of lesions infected with HPV towards malignancy or the reactivity to IFN gamma of such lesions. However, enhanced synthesis of EGF receptors is probably independent of the antiproliferative effect of IFN gamma but an increase in HLA-DR antigen expression by epithelial cells, which corresponds to an immune response favored by IFN gamma, could act synergistically with cell growth inhibition and differentiation to exclude tumoral and/or HPV-infected cells.

Elevated relative fluorescence intensity of CD38 antigen expression on CD8 T cells is a marker of poor prognosis in HIV infection: Results of 6 years of follow‐up

Relative fluorescence intensity measurements from a flow cytometer were used to evaluate expression of CD38 and HLA-DR antigens. These molecules are associated with cellular activation and are present at increased levels on the CD8+ lymphocytes of HIV-infected subjects. In the current study, the prognostic value of mean fluorescence intensity measurements of CD38 and HLA-DR on CD8+ cells was compared to results from our previous study in which we reported prognostic value for an elevated percentage of CD8+ cells that were positive for expression of the CD38 antigen (Giorgi et al.: JAIDS 6:904–912, 1993). Using the proportional hazards model, elevated mean fluorescence intensity of CD38 expression on CD8+ cells had prognostic value for development of AIDS that was almost identical to the prognostic value of the percentage of CD8+ cells that were positive for expression of CD38. This prognostic value was in addition to that provided by the patient's CD4+ cell measurement. To our knowledge, this is the first report that a measurement of fluorescence intensity can be used as a prognostic marker in an immunodeficiency disease. Efforts are needed to establish methods that will allow widespread application of this observation in the clinical management of HIV-infected subjects. © 1996 Wiley-Liss, Inc.

Elevated relative fluorescence intensity of CD38 antigen expression on CD8+ T cells is a marker of poor prognosis in HIV infection: results of 6 years of follow-up.

Relative fluorescence intensity measurements from a flow cytometer were used to evaluate expression of CD38 and HLA-DR antigens. These molecules are associated with cellular activation and are present at increased levels on the CD8+ lymphocytes of HIV-infected subjects. In the current study, the prognostic value of mean fluorescence intensity measurements of CD38 and HLA-DR on CD8+ cells was compared to results from our previous study in which we reported prognostic value for an elevated percentage of CD8+ cells that were positive for expression of the CD38 antigen (Giorgi et al.: JAIDS 6:904-912, 1993). Using the proportional hazards model, elevated mean fluorescence intensity of CD38 expression on CD8+ cells had prognostic value for development of AIDS that was almost identical to the prognostic value of the percentage of CD8+ cells that were positive for expression of CD38. This prognostic value was in addition to that provided by the patient's CD4+ cell measurement. To our knowledge, this is the first report that a measurement of fluorescence intensity can be used as a prognostic marker in an immunodeficiency disease. Efforts are needed to establish methods that will allow widespread application of this observation in the clinical management of HIV-infected subjects.

HLA-DR antigen expression in colorectal carcinomas: influence of expression by IFN-gamma in situ and its association with tumour progression.

The authors attempted to investigate the host's immune response against colorectal carcinoma through the expression of HLA-DR antigen on carcinoma cells (Ca) on normal epithelia immediately adjacent to carcinoma (AN) in relation to tumour progression. The expression of HLA-DR antigen on Ca and on normal epithelia, both on AN and those 5-10 cm removed from the carcinoma (RN), were examined immunohistochemically. mRNAs of cytokines, IFN-gamma and TNF-alpha, were detected by reverse transcription-polymerase chain reaction (RT-PCR) in both carcinoma and remote normal tissues. The expression of HLA-DR antigen on AN was significantly increased compared with RN. Patients with tumours showing HLA-DR staining both in Ca and AN were in less advanced Dukes' stages (Dukes' A or B) compared with those without the stain. Furthermore, the expression of HLA-DR antigen in normal mucosa coincided significantly with the existence of IFN-gamma mRNA. Detection in carcinoma tissues of IFN-gamma mRNA that leads to the induction of HLA-DR antigen on AN could be an indicator of a host's immune response to carcinoma. These in vivo observations might be clinically applicable to the prediction of patients' immune responsiveness to carcinomas.

1,25-dihydroxyvitamin D3 stimulates phagocytosis but suppresses HLA-DR and CD13 antigen expression in human mononuclear phagocytes.

This study investigated the regulatory activity of 1,25-dihydroxyvitamin D3 (1,25-[OH]2D3) on phagocytic cells obtained from normal human peripheral blood. Flow cytometric analysis enabled identification of two discrete populations of cells, one predominantly monocytes ("monocyte" gate) and one containing primarily lymphoid and other cell types ("lymphoid" gate). The monocyte-associated antigens CD13 and CD33 were highly expressed by cells in this monocyte gate and used to monitor this population. Following 5 days of culture, cells in the monocyte gate manifested high phagocytic activity as determined by ingestion of fluorescent carboxylmicrospheres and exhibited high expression of class II HLA-DR products. 1,25-(OH)2D3 profoundly upregulated phagocytic activity while downregulating HLA-DR antigen expression on the cells in the monocyte gate. Moreover, 1,25-(OH)2D3 also reduced cell surface CD13 expression on the cells with low but not high phagocytic activity in this gate. Proportional activities by the 1,24-(OH)2D3 and 24,25-(OH)2D3 metabolites indicated the regulatory effects are likely mediated by the 1,25-(OH)2D3 receptor (VDR). Prostaglandin E2 (PGE2), a known modulator of monocyte/macrophage activity also markedly inhibited HLA-DR expression while enhancing the phagocytic activity of cells in the monocyte gate. In contrast to 1,25-(OH)2D3, PGE2 clearly upregulated CD13 expression in cells with high phagocyte activity. Since indomethacin, an inhibitor of PGE2 synthesis, failed to reverse the 1,25-(OH)2D3 induced inhibitory effect on HLA-DR expression, this effect is apparently not mediated through endogenous PGE2 synthesis. Based on these findings we speculate that 1,25-(OH)2D3 may be capable of acting as both an upregulating agent during natural immunity via the enhancement of phagocytosis by monocyte/macrophage populations and as a "downregulator" during acquired immune responses via an inhibitory effect on MHC class II antigen expression by professional antigen-presenting cells.