Extremely low frequency pulsed electromagnetic fields increase cell proliferation in lymphocytes from young and aged subjects

The effect of the in vitro exposure to extremely low frequency pulsed electromagnetic fields (PEMFs) on the proliferation of human lymphocytes from 24 young and 24 old subjects was studied. The exposure to PEMFs during a 3-days culture period or during the first 24 hours was able to increase phytohaemagglutinin-induced lymphocyte proliferation in both groups. Such effect was greater in lymphocytes from old people which showed a markedly reduced proliferative capability and, after PEMF exposure, reached values of 3H-TdR incorporation similar to those of young subjects. The relevance of these data for the understanding and the reversibility of the proliferative defects in cells from aged subjects and for the assessment of risk related to the environmental exposure to PEMFs has to be considered.     

Early disturbance of the circadian rhythm of T and B lymphocytes in human immunodeficiency virus infection

Circadian rhythms in circulating B and T (CD3, CD4, CD8) lymphocyte subsets and in plasma cortisol were studied in 13 HIV-infected men and 14 healthy male controls. The circadian maximum (acrophase) of plasma cortisol was similar in both groups, approximately 8.00 A.M., however, a statistically significant increase was found in the 24 hour-mean value (mesor) of infected patients as compared to healthy controls. Circadian rhythms were statistically validated in all lymphocyte subsets of healthy controls, whereas, large alterations were found in patients with acquired immunodeficiency syndrome (AIDS), already in asymptomatic infected individuals. The alterations concern the mesor and the amplitude for B and CD4 lymphocytes and all cycle parameters for CD3 and CD8 lymphocytes.     

Interleukin 2 production and responsiveness in individuals with acquired immunodeficiency syndrome and the generalized lymphadenopathy syndrome

Proliferative responsiveness to, and production of, interleukin 2 (IL-2) was determined in 9 homosexually active men with the acquired immunodeficiency syndrome (AIDS) and in 28 homosexually active men with the persistent generalized lymphadenopathy syndrome (PGL). All were seropositive for antibody to human T-lymphotrophic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV). Purified T lymphocytes from individuals with AIDS and PGL had a significantly decreased (P less than 0.01) proliferative response to a saturating amount of exogenous, purified IL-2 as compared to seronegative male controls. Similarly, T4+-enriched T lymphocytes also had a significantly decreased proliferative responsiveness to IL-2 (AIDS, P less than 0.05; PGL, P less than 0.005). T8+-enriched T lymphocytes from individuals with AIDS or PGL did not suppress the IL-2-induced proliferation of autologous T4+ T lymphocytes. In addition, production of IL-2 was significantly decreased in the AIDS group (P less than 0.01) and the PGL group (P less than 0.005) with median values of IL-2 produced being 0.1 and 1.0 U/ml, respectively, compared to 9.9 U/ml for control. These findings demonstrate that substantial quantitative and qualitative abnormalities of the IL-2-T-lymphocyte system exist in patients with AIDS as well as in relatively healthy individuals with PGL. These defects are likely important contributing factors to the depressed T-lymphocyte functions commonly observed in HTLV-III/LAV-associated diseases.     

Human immunodeficiency virus-specific circulating CD8 T lymphocytes have down-modulated CD3zeta and CD28, key signaling molecules for T-cell activation

Although human immunodeficiency virus (HIV)-infected subjects without AIDS have a high frequency of HIV-specific CD8 T lymphocytes, cellular immunity is unable to control infection. Freshly isolated lymphocytes often do not lyse HIV-infected targets in 4-h cytotoxicity assays. A large fraction of circulating CD8 T cells from HIV-infected donors down-modulate CD3zeta, the signaling component of the T-cell receptor complex, which is reexpressed in vitro coincident with the return of cytotoxic function. To investigate further the link between CD3zeta down-modulation and possible CD8 T-cell functional defects, we used flow cytometry to characterize further the properties of the CD3zeta-down-modulated subset. HIV-specific CD8 T cells, identified by tetramer staining, are CD3zeta(-). CD8 T cells with down-modulated CD3zeta also do not express the key costimulatory receptor CD28 and have the cell surface phenotype of activated or memory T cells (HLA-DR(+) CD62L(-)). After T-cell activation, CD3zeta-down-modulated cells express the activation marker CD69 but not the high-affinity interleukin 2 (IL-2) receptor alpha-chain CD25 and produce gamma interferon but not IL-2. Therefore HIV-specific CD8 T cells have down-modulated key signaling molecules for T-cell activation and costimulation and require exogenous cytokine stimulation. The typical impairment of HIV-specific CD4 T helper cells, which would normally provide specific CD8 T-cell stimulation, means that in vivo CTL function in vivo is compromised in most HIV-infected individuals. In AIDS patients, the functional defect is more severe, since CD3zeta is not reexpressed even after IL-2 exposure.     

Impairment of in vitro natural antibacterial activity in HIV-infected patients

Circulating PBMC of healthy subjects possess an in vitro natural antibacterial (NA) against enteropathogenic bacteria, including Salmonella species. The effector cell of NA activity is a CD: 4+, 8-, Leu-8/TQ-1+ T lymphocyte acting against bacteria via cytophylic IgA in a mechanism similar to antibody-dependent cellular activity. Because AIDS is a profound immunodeficiency caused by HIV involving primarily CD4 lymphocytes and in particular the Leu-8/TQ-1 subset, it was of interest to assess NA activity of HIV+ subjects at various stages of the disease. Results indicate that NA activity against Salmonella typhi and Salmonella paratyphi C is significantly decreased in AIDS as well as in lymphadenopathy syndrome patients. Furthermore, sera containing IgA against salmonellae were not able to arm PBMC from HIV+ patients. The humoral response against S. typhi-LPS was also greatly decreased after HIV infection, in contrast to the known hypergammaglobulinemia seen in these subjects. Defective NA activity might contribute to the increased incidence of salmonellosis observed in AIDS.     

脉冲电磁场对家猪淋巴细胞的细胞遗传学效应

以家猪外周血淋巴细胞为材料,研究了脉冲电磁场（pulsing electromagnetic fields,简称PEMFS)树细胞的遗传学效应,实验发现,100和200kHz的PEMFs对家猪的淋巴细胞照射培养12,24,48h后,染色体畸变（包括非整倍体,染色体断裂等）频率明显高于对照组（P＜0．05）,其中,56％的染色体或染色单体断裂和42％的间隙发生在家猪常见染色体脆性位点部位,同时, 经100kHz和200kHz的PEMFs照射48h后,淋巴细胞姐妹染色单体交换（SCE）频率也明显高于对照组（P＜0．05）,实验结果表明,PEMFS能诱导DNA损伤和染色体畸变。     

Effect of Low-Frequency Low-Energy Pulsing Electromagnetic Fields on the Response to Lectin Stimulation of Human Normal and Chronic Lymphocytic Leukemia Lymphocytes

Many literature reports suggest that at least one of the mechanisms of action of low-frequency pulsing electromagnetic fields (PEMFs) is to favor Ca++ movement into the cell. Ca¹ influx Is a fundamental step In the activation process of lymphocytes by lectins. We report here the results of the exposure of human normal and chronic lymphocytic leukemia (CLL) lymphocytes to lectins and PEMFs. Simultaneous exposure to PEMFs and mitogens significantly increased the number of normal responsive lymphocytes compared to those exposed to the mitogens alone. Almost all the normal lymphocytes entered into the mitotic cycle. The number of CLL lymphocytes stimulated by simultaneous exposure to PEMFs and lectins was doubled compared with lectin exposure alone. Ca^?1 influx was increased when the cultures were exposed to PEMFs. The stimulatory effect of PEMFs was mediated by an increased release of some B-cell growth factor by the T-Zymphocytes.     

Defective in vitro T cell colony formation in the acquired immunodeficiency syndrome

Depressed T cell immunity is a universal characteristic of the acquired immunodeficiency syndrome (AIDS). In the present study, 25 patients with AIDS and opportunistic infections, 22 individuals with AIDS-related complex (ARC, or chronic lymphadenopathy syndrome), and 20 healthy homosexuals were evaluated by means of the T cell colony assay. Forty-seven healthy heterosexual controls showed an average of 3964 +/- 319 colonies/7.5 X 10(5) cells, with a range of 880 to 9340. The mean in the 20 healthy homosexuals (3173 +/- 483) did not differ significantly from the controls; in this group, only three patients had values less than 1000 colonies/plate. By contrast, all AIDS patients and 14 ARC patients had colony counts less than 1000. The mean value for the AIDS patients was only 24 +/- 15 (p less than 0.0005 compared with either controls or healthy homosexuals); values in the ARC group were intermediate (1180 +/- 360). The addition of interleukin 2 to the plates promoted correction of the proliferative abnormality in ARC patients. This interleukin increased colony scores in the AIDS group, but the mean value was still significantly less than controls. Comparison indicated that the colony assay is a more sensitive indicator for detecting proliferative abnormalities than responses to PHA, Con A, or pokeweed mitogen in suspension cultures.     

中国新疆维族人群HLA-B等位基因与HIV-1感染易感性或抗性

通过对中国维吾尔族人群HLA-B等位基因的分布频率的研究,探讨HLA-B等位基因与HIV感染的易感 或抵抗性的相关性。本研究用PCR-SSP的方法对新疆维吾尔族110例无相关的健康对照者(HIV阴性)和128例 HIV阳性感染者进行HLA-B等位基因分型。用POPGEN软件对健康对照者人群进行Hardy-Weinberg平衡检 测,用卡方检验分析HLA-B等位基因在健康对照者和HIV阳性感染者频率分布的差异。在HIV-1阳性感染者 中,B*4901等位基因频率显著性增加(B*4901:P=0．02．OR=3．06,95%CI=1．16～8．10)。而在健埭对照者 中,B*40等位基因顿率增加具有统计意义(B*40:P=0．02．OR=0．39．95％CI=0．07～0．92)。由此可见,B* 4901等位基因可能与HIV-1感染的易感性有关,而B*40等位基因可能与与HIV-1感染的抵抗性有关。     

The anti-idiotypic antibody 1F7 selectively inhibits cytotoxic T cells activated in HIV-1 infection

Circulating CD8+ T lymphocyte numbers rise substantially following infection with HIV-1. This expanded CD8+ T cell population includes HIV-specific CTL and CTL that kill activated uninfected CD4+ lymphocytes. Experimental, epidemiological and clinical evidence supports the possibility that expansion of CD8+ CTL contributes to CD4+ T cell depletion and disease progression in human HIV infection. Therefore, modulation of CD8+ T cell numbers or of certain CD8+ CTL activated in HIV-infected individuals may be beneficial. It was found that 1F7, a mAb against an idiotype common to anti-HIV and anti-simian immunodeficiency virus (SIV) antibodies, selectively inhibited both anti-HIV CTL and CTL against uninfected CD4+ T cells. Alloantigen-specific CTL and NK cells from either HIV-infected individuals or controls were unaffected by 1F7. Prolonged incubation of CD8+ T cells from HIV-infected individuals with 1F7 induces apoptosis, which was shown to be reflected functionally in reduced total CTL activity and in especially reduced CTL activity against uninfected CD4+ lymphocytes. The selective reactivity of 1F7 with certain CD8+ CTL could be applied towards the modulation of CD8+ T cell responses involved in AIDS pathogenesis.     

CD4+CD25+FoxP3+ 调节性T 细胞与黑龙江省HIV/AIDS 患者病情 相关性的研究

目的:比较黑龙江省HIV/AIDS患者与健康对照者(healthy controls,HCs)外周血CD4+CD25+FoxP3+调节性T细胞数量、免疫抑制功能的变化,探讨CD4+CD25+FoxP3+调节性T细胞在HIV/AIDS感染过程中的作用。方法:采用流式细胞仪检测21例HIV/AIDS患者及20例健康对照组的外周血CD4+CD25+FoxP3+调节性T细胞数量的百分比及绝对数量;采用共同培养方法检测HIV/AIDS患者外周血CD4+CD25+FoxP3+调节性T细胞免疫抑制功能的变化;实时荧光定量聚合酶链反应(RT-FQ-PCR)检测HIV/AIDS患者外周血CD4+CD25+FoxP3+调节性T细胞中FoxP3mRNA的表达。结果:黑龙江省HIV/AIDS患者外周血CD4+CD25+FoxP3+调节性T细胞比率明显高于HCs(P<0.01),而CD4+CD25+FoxP3+调节性T细胞的绝对计数显著下降,且与CD4+T细胞绝对计数成反比;混合淋巴细胞共同培养结果显示,HIV/AIDS患者外周血CD4+CD25+FoxP3+调节性T细胞的抑制功能无明显变化;HIV/AIDS患者外周血CD4+CD25+FoxP3+调节性T细胞的FoxP3 mRNA相对表达量无显著变化。结论:黑龙江省HIV/AIDS患者CD4+CD25+FoxP3+调节性T细胞的数量变化与病情相关。     

HIV epidemiology: past, present, and future

The worldwide pandemic of acquired immunodeficiency syndrome (AIDS) has the potential to cause catastrophic medical and social effects that will influence world health well into the 21st century. The causative agent, a lentiretrovirus called human immunodeficiency virus (HIV-1), is spread by intimate exposure to blood and bodily fluids through sexual, parenteral, and mother-to-infant exposure. The natural history from exposure to disease has a median incubation period of 8-10 years and is characterized by progressive depletion of CD-4 positive T lymphocytes as well as effects on other immune and central nervous system cell populations. The World Health Organization (WHO) estimates that between 8 and 10 million persons are currently infected with the virus worldwide, with 8 to 10 times this level projected by some estimates into the 21st century. Recent leveling off of AIDS incidence in the U.S. appears to represent the positive benefits of antiretroviral therapy, and considerable benefit could be seen if such therapies were made more widely available to medically underserved populations. With prolonged survival, however, other long-term sequelae such as cancer and lymphoma may emerge as significant complications of prolonged immunodeficiency. Furthermore, the large pool of already infected persons and continued spread of the virus make the development of additional therapies and an effective anti-HIV vaccine priorities of medical research.     

Evaluation of lymphocyte differentiation in primary and secondary immunodeficiency diseases

The differentiation status of T and B cells was evaluated in patients with common variable immunodeficiency (CVI), selective IgA deficiency (IgA), X-linked agammaglobulinemia (XLA), and the acquired immune deficiency syndrome (AIDS) with the use of conventional lymphocyte markers and four new monoclonal antibodies that identify lymphocyte subpopulations. These antibodies are HB 4, which identifies a subpopulation of resting B cells; HB 5, which identifies the C3d/EBV receptor on mature B cells; HB 7, which identifies immature B lymphocytes; and HB 10, which reacts with virgin but not activated or memory T cells. T and B cells from the IgA patients typically had normal phenotypic profiles, whereas diverse patterns of lymphocyte maturation were observed in CVI. In 11 of 16 CVI patients, B cells had normal antigenic phenotypes. Although B cells from four other CVI patients had normal frequencies of HB 5 and HB 7 antigen expression, few expressed the HB 4 antigen, suggesting that they were activated. In contrast, a large percentage of B cells from one CVI patient were of an immature phenotype. The expression of the HB 10 antigen by T cells in CVI patients was also variable, being normal in 10 of 16 patients, yet significantly decreased in six others. The vast majority of the limited numbers of IgM B cells from five XLA patients (greater than 100-fold reduction) has an immature phenotype (HB 4-5-7+). Interestingly, the circulating T cells in XLA patients were phenotypically similar to those in normal newborns, suggesting that T cell immaturity or defective T cell activation may occur in these B cell-deficient individuals. Circulating B cells from AIDS patients were mostly HB 7-, with variable expression of the HB 4 antigen and significantly decreased expression of the HB 5 antigen. Most of the T cells from AIDS patients were HB 10-, and thus appeared to be activated.     

Interleukin-8 stimulates human immunodeficiency virus type 1 replication and is a potential new target for antiretroviral therapy

Production of the C-X-C chemokines interleukin-8 (IL-8) and growth-regulated oncogene alpha (GRO-alpha) in macrophages is stimulated by exposure to human immunodeficiency virus type 1 (HIV-1). We have demonstrated previously that GRO-alpha then stimulates HIV-1 replication in both T lymphocytes and macrophages. Here we demonstrate that IL-8 also stimulates HIV-1 replication in macrophages and T lymphocytes. We further show that increased levels of IL-8 are present in the lymphoid tissue of patients with AIDS. In addition, we demonstrate that compounds which inhibit the actions of IL-8 and GRO-alpha via their receptors, CXCR1 and CXCR2, also inhibit HIV-1 replication in both T lymphocytes and macrophages, indicating potential therapeutic uses for these compounds in HIV-1 infection and AIDS.     

The Vancouver Lymphadenopathy-AIDS Study: 5. Antecedent behavioural,clinical and laboratory findings in patients with AIDS and HIV-seropositive controls.

In a group of homosexual men in Vancouver studied prospectively since November 1982, 26 cases of acquired immune deficiency syndrome (AIDS) have arisen. To identify behavioural, clinical and laboratory findings that might predict the development of AIDS in people with antibody to human immunodeficiency virus (HIV), we compared data for 25 patients with AIDS with corresponding data for 80 controls serologically positive for HIV selected from the cohort. The clinical and laboratory data for the patients with AIDS preceded the diagnosis of the syndrome by a mean of 17.5 months. The controls had been both seropositive and AIDS-free for a mean of 16.7 months after acquisition of their data. We detected significant differences between the patients with AIDS and the controls in IgG and IgA levels, absolute number of helper T cells and ratio of helper to suppressor T cells but not in lifetime number of male sexual partners, frequency of receptive anal intercourse or receptive fisting, illicit drug use or history of infectious disease. We also detected an increased risk of AIDS among those who had an elevated number of sexual contacts in AIDS-endemic areas in the 5 years before enrollment. A history of increased early sexual contact in AIDS-endemic areas is likely to be associated with early infection and with an increased risk of AIDS among men with HIV infection of unknown duration. Thus, although our analysis had limited statistical power, we conclude that most lifestyle variables appear to act as exposure factors in HIV infection but not as cofactors in the development of AIDS.     

Activated peripheral CD8 lymphocytes express CD4 in vivo and are targets for infection by human immunodeficiency virus type 1.

There is increasing evidence that CD8 lymphocytes may represent targets for infection by human immunodeficiency virus type 1 (HIV-1) in vivo whose destruction may contribute to the loss of immune function underlying AIDS. HIV-1 may infect thymic precursor cells destined to become CD4 and CD8 lymphocytes and contribute to the numerical decline in both subsets on disease progression. There is also evidence for the induction of CD4 expression and susceptibility to infection by HIV-1 of CD8 lymphocytes activated in vitro. To investigate the relationship between CD8 activation and infection by HIV-1 in vivo, activated subsets of CD8 lymphocytes in peripheral blood mononuclear cells (PBMCs) of HIV-seropositive individuals were investigated for CD4 expression and HIV infection. Activated CD8 lymphocytes were identified by expression of CD69, CD71, and the human leukocyte antigen (HLA) class II, the beta-chain of CD8, and the RO isoform of CD45. CD4(+) and CD4(-) CD8 lymphocytes, CD4 lymphocytes, other T cells, and non-T cells were purified using paramagnetic beads, and proviral sequences were quantified by PCR using primers from the long terminal repeat region. Frequencies of activated CD8 lymphocytes were higher in HIV-infected study subjects than in seronegative controls, and they frequently coexpressed CD4 (mean frequencies on CD69(+), CD71(+), and HLA class II(+) cells of 23, 37, and 8%, respectively, compared with 1 to 2% for nonactivated CD8 lymphocytes). The level of CD4 expression of the double-positive population approached that of mature CD4 lymphocytes. That CD4 expression renders CD8 cell susceptible to infection was indicated by their high frequency of infection in vivo; infected CD4(+) CD8 lymphocytes accounted for between 3 and 72% of the total proviral load in PBMCs from five of the eight study subjects investigated, despite these cells representing a small component of the PBMC population (<3%). Combined, these findings provide evidence that antigenic stimulation of CD8 lymphocytes in vivo induces CD4 expression that renders them susceptible to HIV infection and destruction. The specific targeting of responding CD8 lymphocytes may provide a functional explanation for the previously observed impairment of cytotoxic T-lymphocyte (CTL) function disproportionate to their numerical decline in AIDS and for the deletion of specific clones of CTLs responding to HIV antigens.     

B-lymphocyte dysfunction in chronic HIV-1 infection does not prevent cross-clade neutralization breadth

Aberrant expression of regulatory receptors programmed death-1 (PD-1) and B- and T-lymphocyte attenuator (BTLA) is linked with dysregulation and exhaustion of T lymphocytes during chronic human immunodeficiency virus type 1 (HIV-1) infection; however, less is known about whether a similar process impacts B-lymphocyte function during HIV-1 infection. We reasoned that disruption of the peripheral B cell compartment might be associated with decreased neutralizing antibody activity. Expression of markers that indicate dysregulation (BTLA and PD-1), immune activation (CD95), and proliferation (Ki-67) was evaluated in B cells from HIV-1-infected viremic and aviremic subjects and healthy subjects, in conjunction with immunoglobulin production and CD4 T cell count. Viral load and cross-clade neutralizing activity in plasma from viremic subjects were also assessed. Dysregulation of B lymphocytes was indicated by a marked disruption of peripheral B cell subsets, increased levels of PD-1 expression, and decreased levels of BTLA expression in viremic subjects compared to aviremic subjects and healthy controls. PD-1 and BTLA were correlated in a divergent fashion with immune activation, CD4 T cell count, and the total plasma IgG level, a functional correlate of B cell dysfunction. Within viremic subjects, the total IgG level correlated directly with cross-clade neutralizing activity in plasma. The findings demonstrate that even in chronically infected subjects in which B lymphocytes display multiple indications of dysfunction, antibodies that mediate cross-clade neutralization breadth continue to circulate in plasma.     

Changes in serum markers indicative of health effects in vineyard workers following exposure to the fungicide mancozeb: an Italian study

The aim of this study was to investigate the health effects induced by exposure to the fungicide mancozeb in Italian vineyard workers. Ninety-three Italian subjects entered the study - 48 vine-growers intermittently exposed to mancozeb and 45 healthy controls. The subjects were investigated three times: before the seasonal application of pesticides (T0), 30 days after the beginning of the application period (T30), and 45 days after T0 (T45). At T0 the comparison between agricultural workers and controls showed a higher prevalence of cold or flu symptoms, a statistically significant lower percentage of monocytes, higher absolute count of T lymphocytes, CD4 and natural killer cells, and lower plasma levels of IgA and IgM in workers. Such differences were not confirmed at T30 and T45. In fact at T30 in exposed workers, besides a significant increase of urinary ethylenethiourea, confirming mancozeb exposure, T lymphocytes, CD4 and natural killer cells, IgA and IgM returned to values comparable to those observed in controls. Moreover, no other differences in clinical signs, haematological, and immune parameters, such as the immune functional capability evaluated as a response to hepatitis B vaccination, was observed. Altogether the differences between exposed and controls were not consistently correlated to any clinical impairment and suggest that the seasonal application of mancozeb does not pose a significant health risk to exposed subjects.     

IgG-antibodies to HTLV-III in patients with AIDS, LAS, and persons at risk of AIDS in West Germany

In a first seroepidemiological study on the prevalence of the human T-lymphotropic retrovirus HTLV-III in West Germany, sera of 26 patients with acquired immunodeficiency syndrome (AIDS), 33 patients with lymphadenopathy syndrome (LAS) or AIDS related complex (ARC), and 113 homosexual men at risk of AIDS were screened for IgG antibodies to HTLV-III by an enzyme linked immunosorbent assay (ELISA). 22 out of 26 AIDS-patients (84.6%), 24 out of 33 LAS-patients (72.7%), and 44 out of 113 healthy homosexual men with increased risk of AIDS (38.9%) were found positive for antibodies to HTLV-III. Heterosexual controls including healthy laboratory workers and medical personnel with contact to AIDS patients did not show antibodies to HTLV-III. The HTLV-III antibodies analyzed predominantly recognize a protein of molecular weight 41,000 (p41).