Habib Abul

Lymphocyte subpopulations in pregnancy complicated by hypertension

The immune responsiveness of women is altered during pregnancy in order to retain protective properties against disease and at the same time allow tolerance of the fetus. Diseases such as pre-eclampsia (PE) have been suggested to arise as a result of maladaptations in these immune alterations. Here we evaluate the effect of PE on the composition of peripheral blood lymphocyte subpopulations using lymphocyte surface antigen expression. Fifty-four women of various parities with pregnancy-induced hypertension (PIH) (39 non-proteinuric and 14 proteinuric) and matched controls (30 normotensive pregnant women (NTP) and 15 healthy non-pregnant women (NP)) were investigated. Monoclonal antibodies specific for human T lymphocytes and subpopulations: CD2, CD3, CD4, CD8, CD19 and activation markers: CD25, CD45RA, CD45RO, CD54 AND HLA m DR were used and detected using a two-colour fluorescence analysis with an automated flow cytometer. The total number of T lymphocytes: CD2, CD3, CD4, CD8 and CD19 were significantly decreased in PIH particularly PE ( P <0.05). T cells expressing NK surface markers (CD3/CD16 + CD56) and CD4 cells expressing HLA m DR were higher in PE. CD8 + HLA m DR + cells and T-helper cells expressing adhesion molecules) CD4 + CD54 + ) were higher in NTP than in NP and PE ( P <0.05, 0.05). PE is associated with elevated levels of CD4 + HLA m DR + , and CD3 + NK cells but decreased total numbers of T lymphocytes, and the CD3 + CD25 + subpopulation. These findings indicate systemic alterations in maternal immunity associated with the PE state. This feature of the disease may contribute to abnormal adaptation to pregnancy resulting in PE and PIH, promoting adverse outcomes including pregnancy loss.

Pregnancy-Associated Changes in Peripheral Blood Lymphocyte Subpopulations in Normal Kuwaiti Women

It has recently been reported that healthy pregnancy is associated with systemic immunosuppression. The aim of this study was to evaluate the numbers and distribution of lymphocyte subpopulations in normal, healthy pregnant Kuwaiti women. Thirty-four healthy normotensive women in the 3rd trimester of pregnancy were studied using flow cytometry to define lymphocyte subpopulations and were compared with 16 non-pregnant women. A decrease in the absolute numbers of lymphocytes was observed affecting T cells (CD3+, CD4+, CD8+), B cells (CD19+), and natrural killer cells (CD16+/CD56+). When analyzed as a percentage of the total lymphocyte population, there was a significant decrease in B cells and an increase in CD4+ T cells. The T cell population revealed increased expression of CD25 on CD4+ and CD8+ cells, of HLA-DR on CD8+ cells, and of CD54 on CD4+ T cells. The reduced number of lymphocytes suggests that Kuwaiti females may be immunosuppressed in the 3rd trimester of pregnancy. The presence of activated CD4+ T cells could indicate the expression of a regulatory suppressor T cell population, as Treg cells are CD4+CD25+, and suppressor T cells are thought to be CD8+. Future work is required to explore the significance of these T cell populations in pregnancy.

SELENIUM AND LIVER CIRRHOSIS

Effects of selenium deficiency, induced by thioacetamide, were investigated in rats. Thioacetamide (0.3 g/L) given in drinking water, as expected, caused a significant loss of selenium from the liver. It was accompanied by liver cirrhosis and a significant increase in the liver weight as well as liver to body weight ratio. A significant loss of selenium from spleen was also accompanied by an increase in its weight. Weights of lungs, testis and kidney, however, were not affected by thioacetamide and there was no change in their selenium content. Plasma levels of selenium were significantly reduced in the thioacetamide treated group. All these changes were confirmed to be due to selenium deficiency caused by thioacetamide, as supplementation with selenium reversed these changes. The mode of action of selenium is unknown but may involve anti-oxidant defense mechanisms.

Cholangiocarcinoma and liver cirrhosis in relation to changes due to thioacetamide

Different doses of thioacetamide (0.05, 0.1 and 0.15%) were used to induce liver cirrhosis in Wistar rats. Thioacetamide at 0.5% caused cirrhosis by the twelfth week of treatment. A severe bile duct proliferation and cholangiocarcinoma was seen at longer intervals. Animals treated with higher doses (0.1 and 0.15%) of thioacetamide developed more severe intense degenerative changes in the liver and died in the twelfth and eighth week respectively. The serum and tissue contents of Zn and Cu changed in a characteristic fashion that was consistent with the severity of the liver damage. Serum Zn and Cu concentrations were at their lowest in the animals that developed severe degenerative liver and died at higher dose (0.15%) of thioacetamide.This study indicates that treatment of rats with 0.05% thiocetamide is more effective and appropriate for the induction of liver cirrhosis. Continued administration of the drug at this dosage led to the development of further changes in the liver. This model may be suitable for studying these long term changes that occur in the liver and lead to cirrhosis. Events that precede the development of severe bile duct proliferation and cholangiocarcinoma may also be studied.

Decreased Total Numbers of Peripheral Blood Lymphocytes with Elevated Percentages of CD4+CD45RO+ and CD4+CD25+ of T-Helper Cells in Non-Segmental Vitiligo

Vitiligo is a disorder involving progressive skin depigmentation caused by host mediated destruction of melanocytes. Its pathogenesis is known to correlate with elevated levels of activated skin‐infiltrating T lymphocytes and is presumed to be autoimmune in nature. In the present study, we characterize the immunophenotype of peripheral blood T cells from vitiligo patients, with the objective of developing an investigative and diagnostic tool for the disease, using analysis of peripheral blood. Subjects for this investigation included 32 patients diagnosed with non‐segmental vitiligo and 28 age‐and gender‐matched, normal, healthy control participants. Whole venous blood taken from each subject was analyzed using 2‐color flow cytometry for immunologically‐relevant lymphocyte subsets. When compared with healthy control subjects, peripheral blood from individuals with vitiligo was found to have lower total numbers of lymphocytes (p<0.039). Vitiligo patients also had elevated percentages of memory (CD4+CD45RO+) T cells; (p<0.05), but NK‐T cells (CD3+CD16+CD56+) and naive T cells (CD4+CD45RA+) were present at lower total numbers and percentages than in healthy controls (p<0.01 and 0.05 respectively). Blood from severely afflicted subjects exhibited elevated CD3+HLADR+ and CD4+CD45RO+ as well as lower percentages of NK‐T cells (p<0.05) when compared with mild cases. In conclusion, disease‐associated, peripheral blood lymphocyte immunophenotypic profiles of vitiligo patients are consistent with the hypothesis of T cell activation as a major feature of the disorder. These include elevated memory and reduced naive T cell percentages and increased expression of the activation‐associated surface antigen CD25. These changes presumably reflect increased antigen‐mediated activation. Moreover, because a corollary effect is increased activation‐induced cell death (AICD), lower overall lymphocyte counts observed in vitiligo‐afflicted subjects is also expected.

Elevated B-lymphocyte levels in lesional tissue of non-arthritic psoriasis.

Psoriasis is a chronic inflammatory skin disorder characterized clinically by maculopapular skin lesions and on the cellular level by increased T‐lymphocyte activation in die peripheral blood and migration of activated T‐lymphocytes into the lesions. The lymphocyte subpopulations in peripheral blood from 21 Kuwaiti patients showed elevated levels of the T‐lymphocyte activation marker CD25, as well as increased expression of HLA‐DR compared with a group of age and sex‐matched controls, confirming published findings on psoriasis. In addition, there was a tendency towards a significant increase in the CD4+/CD45RO+ (memory cell) population that was also consistent with peripheral T‐lymphocyte activation. Immunohistological studies showed a heavy infiltrate of all cell types into the lesional tissue including, as expected, activated T‐lymphocytes. An unexpected finding was significantly higher levels of B‐lymphocytes infiltrating the psoriatic lesions; they numerically exceeded the T‐lymphocyte infiltrate. This has previously been reported only in cases of psoriasis with concurrent arthritis. None of the subjects had arthritis, suggesting an immunopathological variant of psoriasis possibly specific to this population group.

Peripheral T‐Cell Activation in Non‐Segmental Vitiligo

Vitiligo is a hypopigmentary dermatosis of probable autoimmune origin. Previously reported aberrations in peripheral blood mononuclear cells (PBMC), especially T cells and T cell subsets, have been inconsistent. Lymphocyte subpopulations were examined using flow cytometry and monoclonal antibodies against CD4, CD8, CD20, CD25, CD45RA, and HLA‐DR in 34 patients with non‐segmental vitiligo. Twelve patients had not received any previous treatment and 22 had previously received at least one course of PUVA therapy that was discontinued at least four months prior to our study. Compared to matched controls, we found significant increases in CD25 and HLA‐DR in vitiligo patients (p=0.000). An inverse correlation was observed between HLA‐DR and patient status with regard to treatment (p=0.001). These results suggest a role for T cells in the pathogenesis of vitiligo and imply that previous PUVA therapy may be reflected by an alteration in circulating DR + ve cells.

Serum zinc and copper concentrations in pregnant women from Kuwait

Although it is well known that plasma concentrations of certain essential trace elements such as zinc and copper are altered during pregnancy, such data are not available for women in Kuwait. We analyzed the plasma of 120 pregnant Kuwaiti women aged 19–40 years (mean age 27 ± 5.7 years) and 40 controls of similar age. Blood samples from the pregnant women were collected during the first (n = 40), second (n = 40), and third (n = 40) trimesters. The trace elements were analyzed by flame as well as graphite furnace atomic absorption spectrophotometry. The results indicated that the levels of zinc decreased steadily and significantly from the first trimester through the third trimester, with a reciprocal increase in the level of copper during the same period. Thus, the copper/zinc ratio increased steadily from first trimester to the third trimester (3.5 ± 1.8, 3.9 ± 1.1, and 5.8 ± 3.3, respectively) compared to the control ratio, which was 2 ± 1. The maximum decrease in zinc and maximum increase in copper were observed during weeks (35–36) of pregnancy. Such changes could be due to the requirements of the fetus for growth. J. Trace Elem. Exp. Med. 10:209–215, 1997.

Lymphocyte sub-populations in gestational diabetes

Problem:  We hypothesize that the normal immunologic responses by the maternal immune system during pregnancy are not as well‐regulated in gestational diabetes (GD) patients as in healthy pregnant women.

Levels of IL-8 and myeloperoxidase in the lungs of pneumonia patients

Interleukin-8 (IL-8) is considered as the major polymorphonuclear neutrophils (PMNs) chemoattractant cytokine in lung diseases such as asthma and adult respiratory distress syndrome (ARDS). However, controversial results were obtained regarding the involvement of IL-8 in the pathogenesis of pneumonia. This study examines the role of IL-8 in the recruitment and activation of PMNs in the lung of pneumonia patients. The interesting aspect of this study is that it is a site- specific analysis of the infected and uninfected lungs of the same patient. The level of IL-8 mRNA, protein and myeloperoxidase present in the cells of the bronchioalveolar lavages (BALs) taken from the areas of known pneumonic consolidations on chest X-ray (infected lung) are compared with the BALs obtained from areas of no obvious infiltrate (non-infected lung). The results obtained from the infected and non-infected lungs of pneumonic patients were further compared with that of a control group of non-smoking patients. The level of IL-8 mRNA and protein were determined by RT-PCR and ELISA respectively. There was a significant increase in the level of IL-8 mRNA in the infected lung as compared to its level in the non-infected lung (p < 0.001). In correlation with the increase in mRNA, IL-8 protein concentrations in BAL fluids from the infected lung were 6 fold higher than those taken from the non-infected lung (p < 0.0001). This pattern was also consistent with MPO activity in the BALs (4.5 fold more MPO activity in the infected lung as compared to that of the non-infected lung), indicating that IL-8 is directly implicated in neutrophil accumulation that follows acute respiratory infection. The results of the present study, therefore, indicate the involvement of IL-8 in the pathogenesis of pneumonia.