Studies of cellular immunity in male homosexuals in London

Association between Periodontal Disease and Systemic Inflammatory Conditions Using Electronic Health Records: A Pilot Study

AIMS

To investigate the association between periodontal disease and systemic inflammatory conditions and examine the link between medical conditions and the extent of missing teeth in a large population.

METHODS

In this retrospective study, a total of 4890 randomly selected patients who had attended the University of Minnesota dental clinics were analyzed. Severity of periodontal disease was determined based on the percentage of bone loss, evaluated through the examination of a full-mouth intraoral series of radiographs. The number of missing teeth was calculated from the examined radiographs, while ten systemic inflammatory conditions were extracted from patients' self-reported medical histories.

RESULTS

Moderate bone loss was observed in 730 (14.9%) and severe in 323 (6.6%) patients of the total population, while the mean number of missing teeth was 3.54 ± 3.93. The prevalence of systemic conditions and tobacco use were gender-dependent (p < 0.05). Regression analysis showed that hypertension, arthritis, asthma, diabetes and HIV were associated significantly with the severity of bone loss, while diabetes and lupus with the extent of missing teeth.

CONCLUSIONS

The findings reported in our study add to this body of knowledge, strengthening the association between periodontal disease with systemic inflammatory conditions.

A Direct Comparison of Two Densely Sampled HIV Epidemics: The UK and Switzerland

Phylogenetic clustering approaches can elucidate HIV transmission dynamics. Comparisons across countries are essential for evaluating public health policies. Here, we used a standardised approach to compare the UK HIV Drug Resistance Database and the Swiss HIV Cohort Study while maintaining data-protection requirements. Clusters were identified in subtype A1, B and C pol phylogenies. We generated degree distributions for each risk group and compared distributions between countries using Kolmogorov-Smirnov (KS) tests, Degree Distribution Quantification and Comparison (DDQC) and bootstrapping. We used logistic regression to predict cluster membership based on country, sampling date, risk group, ethnicity and sex. We analysed >8,000 Swiss and >30,000 UK subtype B sequences. At 4.5% genetic distance, the UK was more clustered and MSM and heterosexual degree distributions differed significantly by the KS test. The KS test is sensitive to variation in network scale, and jackknifing the UK MSM dataset to the size of the Swiss dataset removed the difference. Only heterosexuals varied based on the DDQC, due to UK male heterosexuals who clustered exclusively with MSM. Their removal eliminated this difference. In conclusion, the UK and Swiss HIV epidemics have similar underlying dynamics and observed differences in clustering are mainly due to different population sizes.

Evaluation of immune responses in HIV infected patients with pleural tuberculosis by the QuantiFERON TB-Gold interferon-gamma assay

Background

Diagnosis of tuberculous (TB) pleuritis is difficult and better diagnostic tools are needed. New blood based interferon-gamma (IFN-γ) tests are promising, but sensitivity could be low in HIV positive patients. The IFN-γ tests have not yet been validated for use in pleural fluid, a compartment with higher level of immune activation than in blood.

Methods

The QuantiFERON TB^®-Gold (QFT-TB) test was analysed in blood and pleural fluid from 34 patients presenting with clinically suspected pleural TB. Clinical data, HIV status and CD4 cell counts were recorded. Adenosine deaminase activity (ADA) analysis and TB culture were performed on pleural fluid.

Results

The patients were categorised as 'confirmed TB' (n = 12), 'probable TB' (n = 16) and 'non-TB' pleuritis (n = 6) based on TB culture results and clinical and biochemical criteria. The majority of the TB patients were HIV infected (82%). The QFT-TB in pleural fluid was positive in 27% and 56% of the 'confirmed TB' and 'probable TB' cases, respectively, whereas the corresponding sensitivities in blood were 58% and 83%. Indeterminate results in blood (25%) were caused by low phytohemagglutinin (PHA = positive control) IFN-γ responses, significantly lower in the TB patients as compared to the 'non-TB' cases (p = 0.02). Blood PHA responses correlated with CD4 cell count (r = 0.600, p = 0.028). In contrast, in pleural fluid indeterminate results (52%) were caused by high Nil (negative control) IFN-γ responses in both TB groups. Still, the Nil IFN-γ responses were lower than the TB antigen responses (p < 0.01), offering a conclusive test for half of the patients. We did not find any correlation between blood CD4 cell count and IFN-γ responses in pleural fluid.

Conclusion

The QFT-TB test in blood could contribute to the diagnosis of TB pleuritis in the HIV positive population. Still, the number of inconclusive results is too high to recommend the commercial QFT-TB test for routine use in pleural fluid in a TB/HIV endemic resource-limited setting.

Pathogenic significance of alpha-N-acetylgalactosaminidase activity found in the envelope glycoprotein gp160 of human immunodeficiency virus Type 1

Serum vitamin D3-binding protein (Gc protein) is the precursor for the principal macrophage-activating factor (MAF). The precursor activity of serum Gc protein was lost or reduced in HIV-infected patients. These patient sera contained alpha-N-acetylgalactosaminidase (Nagalase), which deglycosylates serum Gc protein. Deglycosylated Gc protein cannot be converted to MAF and thus loses MAF precursor activity, leading to immunosuppression. Nagalase in the blood stream of HIV-infected patients was complexed with patient immunoglobulin G, suggesting that this enzyme is immunogenic, seemingly a viral gene product. In fact, Nagalase was inducible by treatment of cultures of HIV-infected patient peripheral blood mononuclear cells with a provirus-inducing agent. This enzyme was immunoprecipitable with polyclonal anti-HIV but not with anticellular constitutive enzyme or with antitumor Nagalase. The kinetic parameters (km value of 1.27 mM and pH optimum of 6.1), of the patient serum Nagalase were distinct from those of constitutive enzyme (km value of 4.83 mM and pH optimum of 4.3). This glycosidase should reside on an envelope protein capable of interacting with cellular membranous O-glycans. Although cloned gp160 exhibited no Nagalase activity, treatment of gp160 with trypsin expressed Nagalase activity, suggesting that proteolytic cleavage of gp160 to generate gp120 and gp41 is required for Nagalase activity. Cloned gp120 exhibited Nagalase activity while cloned gp41 showed no Nagalase activity. Since proteolytic cleavage of protein gp160 is required for expression of both fusion capacity and Nagalase activity, Nagalase seems to be an enzymatic basis for fusion in the infectious process. Therefore, Nagalase appears to play dual roles in viral infectivity and immunosuppression.

Enhancement of human immunodeficiency virus type 1 (HIV-1) infection via increased membrane fluidity by a cationic polymer

Cationic polymers are known to have potent activity against bacteria, but their effects on viral activity have been little studied. We investigated the effect of one such polymer, polyethyleneimine (PEI), on HIV-1 infection. Although virus-cell binding was significantly inhibited by PEI, HIV-1 infection in human T-cell lines such as MT-4 and MOLT-4 was accelerated conversely when the drug treatment was carried out, after the virus had attached to the cells or PEI was simultaneously added to the virus and cell culture system. This paradoxical effect of PEI on HIV-1 infection was examined using HIV-1 chronically infected cells (MOLT-4/HIV-1). Dissociation of the glycoprotein gp120 (as revealed by exposure of transmembrane protein gp41) from MOLT-4/HIV-1 cells and the resultant fusion of these cells was shown to be induced by the addition of PEI. Accordingly, it was suggested that the binding inhibition of HIV-1 to CD4-positive cells by PEI was due to the shedding of gp120 from HIV-1 particles, and this PEI rather promoted membrane fusion between the virus and cells leading to the enhancement of HIV-1 infection. Similarly, dissociation of gp120 from MOLT-4/HIV-1 was also induced by sCD4. The effect of these reagents on changes in membrane fluidity was evaluated by polarization (p) measurements, and it was observed that the acceleration of membrane fluidity occurred only in the PEI system. Therefore, it is likely that PEI accelerates HIV-1 infection by facilitating virus entry into the host cells through an increase in membrane fluidity.

Increase in dendritic cell numbers, their function and the proportion uninfected during AZT therapy

The effects of AZT treatment on the numbers, level of infection and function of peripheral blood dendritic cells (DC) were examined in patients with HIV infection. This was a cross-sectional study of patients before AZT treatment and up to 20 months after initiation of treatment. Numbers of DC separated by density gradients were below the normal range in patients before treatment, but increased between 3 and 12 months of treatment. The numbers of DC per provirus copy rose from around 100 cells to 5000 cells and this decrease in viral load in DC was significant between 3 and 20 months of treatment. The capacity of DC to stimulate allogeneic T cell proliferation was low before treatment and significantly higher between 6 and 12 months after the start of AZT. This study indicated that AZT treatment produced beneficial effects on DC by increasing their numbers, reducing the provirus load and increasing their function in stimulating T cells. These results support the thesis that the function of these potent antigen-presenting cells is important in development of immunological defects in AIDS, and that effects of AZT treatment on DC may provide a measure of its therapeutic effect.

Herpes zoster and the stage and prognosis of HIV-1 infection

OBJECTIVES

To examine the incidence of herpes zoster in HIV-1 infection. To assess the prognostic significance of the occurrence of herpes zoster and progression to AIDS or death

DESIGN AND METHODS

146 homosexually active men with known times of HIV-1 seroconversion were identified through the Sydney AIDS Prospective Study and the clinic records of a private medical practice with large caseload of HIV infected homosexual men. Medical records were reviewed for a history of herpes zoster, CD4+ lymphocyte counts, and HIV-1 disease status. Cox's proportional hazards model was used to determine whether herpes zoster predicted progression to AIDS or death.

RESULTS

After a mean follow up of 54 months, 30 men (20%) had an episode of herpes zoster and three of these men had one recurrence. The overall incidence of herpes zoster was 44.4 episodes per 1000 person years (95% CI 30.0-63.5). Herpes zoster was not found to be a marker of deteriorating immune functions as measured by CD4+ lymphocyte counts. CD4+ counts did not differ significantly between those with and without zoster at 1 year (551 v 572.10(6)/1, p = 0.79), 2 years (451 v 557, p = 0.11), and 3 years (424 v 481, p = 0.50) following HIV-1 seroconversion. There was no statistically significant difference in progression to AIDS (RR = 1.89, 95% CI 0.80-4.46, p = 0.15) or death (RR = 0.90, 95% CI 0.31-2.65, p = 0.85) from HIV-1 sero-conversion in those who did and those who did not develop herpes zoster.

CONCLUSION

The incidence of herpes zoster was consistent with the findings of other studies. There was no association between the occurrence of herpes zoster and progression of HIV-1 disease.

Increased microbicidal activity of human monoblastoid cells upon long-term exposure to dideoxycytidine

2',3'-Dideoxycytidine (ddC) is a nucleoside analogue currently used in AIDS therapy. We had previously found that long term exposure of U937 human monoblastoid cells to ddC induces the selection of drug-resistant cells (U937-R). In the present work we investigated some important biochemical properties and functional activities of these resistant cells. The results obtained show that U937-R maintained the properties of cell aggregation, adhesion and differentiation. Basal respiration, protein kinase C activity, superoxide anion release and intracellular free calcium were all increased in the drug-resistant line. Phagocytosis of fungi (Candida albicans) and bacteria (Staphylococcus aureus and Salmonella anatum) were similar in U937 and U937-R cells. Killing of C. albicans was significantly higher in drug-resistant cells (29.07 +/- 2.23% of killing vs 19.07 +/- 2.01 in the control; p < 0.001). Similarly, the bacterial killing was enhanced in U937-R cells (34.07 +/- 8.06% vs 22.60 +/- 4.41% in the control; p < 0.05). Thus, the results presented in this paper provide evidence of an increased microbicidal activity of human monocytic cells upon long term exposure to ddC, most likely due to an increased oxidative metabolism.

Immunophenotyping of normal lymphocytes

We report the data of direct and indirect immunofluorescence labelling of peripheral blood mononuclear cells obtained from 40 normal controls and nine patients having blood tests for non-haematological disorders (PNHD controls) using flow cytometric analysis. Polyclonal and monoclonal antibodies were used to define the expression of cell surface antigen of T cells, their subsets, B cells, natural killer cells (NK) and myeloid cells. Normal values of absolute number and percentages of each of the populations of mononuclear cells were established and were sufficiently reproducible to be of clinical use. The percentages of positive values of T cells, T-cell subsets, and B cells in ten normal controls when mononuclear cells were used, were comparable to those using whole blood lysis, APAAP immuno-alkaline phosphatase, and E and M rosettes. The results obtained were similar in both the normal and PNHD controls. In most instances the percentage recovery of identified T, B and NK cells was complete. Currently we are using the results as reference values for lymphoid sub-populations in normal controls.

HIV-1 infection of monocyte-derived macrophages reduces Fc and complement receptor expression

Fc receptor (FcR) and complement receptor (CR) expression on HIV-infected monocyte-derived macrophages may be an important determinant of immune function. We studied the effects of HIV-1 infection of macrophages in vitro on FcR and CR expression. Macrophages were infected with HIV-1DV 7 days following isolation, and the expression of Fc gamma RI-III and CR3 were measured at intervals thereafter by flow cytometry. We found a reduction in receptor expression with the percentage of cells expressing FcRI 14 days post infection declining from 77% to 13%, FcRII fell from 96% to 85%, FcRIII from 45% to 9%, and CR3 from 91% to 67% 14 days following infection. As these receptors are important for macrophage function, their down-modulation may contribute to the pathogenesis of HIV-related disease.

Impaired phagolysosomal fusion of peripheral blood monocytes from HIV-infected subjects

We evaluated phagolysosomal fusion in peripheral blood monocytes from 20 HIV-infected individuals and 40 normal controls, using a fluorescence assay with acridine orange as marker. The percentages of phagolysosomal fusion of monocytes from HIV-infected subjects, after 30 and 60 min of yeast ingestion, (mean +/- standard deviation) 57.2 +/- 17 and 63.2 +/- 18.6, respectively, when compared to normal controls (72.4 +/- 7.8 and 77 +/- 8.1), did not differ significantly. However, there was a direct linear association between the percentages of phagolysosomal fusion and CD4+ lymphocytes (P < 0.001) or CD4/CD8 T-cell ratio (P < 0.01). These results suggest that phagolysosomal dysfunction becomes evident at late stages of HIV infection and progresses as CD4+.T-lymphocyte count and CD4/CD8 T-cell ratio decrease. On the other hand, recombinant gp120 inhibited significantly normal phagolysosomal fusion at concentrations ranging between 1 and 1000 ng/ml. Taking together the results obtained, we can conclude that gp120 could be responsible for monocyte phagolysosomal dysfunction observed in HIV infected patients.

Quantitative differences in phagocytosis and degradation of Pneumocystis carinii by alveolar macrophages in AIDS and non-HIV patients in vivo

Bronchoalveolar lavage (BAL) specimens (n = 213) from AIDS and non-HIV immunosuppressed patients were investigated for the presence of Pneumocystis carinii infection by fluorescence microscopy of Papanicolaou-stained slides. Alveolar casts, extracellular pneumocysts and phagocytosed cysts and their degradation products in pulmonary alveolar macrophages were identified. The number of phagocytosed pneumocysts within human pulmonary alveolar macrophages was recorded and correlated with the number of extracellular cysts and alveolar casts, in both groups of patients. Both phagocytic and degradation capacity were depressed in AIDS patients. This observation may explain the large number of extracellular organisms found in BAL specimens of AIDS patients compared with non-HIV-positive immunocompromised individuals.

Reactive oxygen intermediates and human immunodeficiency virus (HIV) infection

HIV infection affects various parts of the immune system, including the CD4+ lymphocytes and mononuclear phagocytes, and causes a progressive immunodeficiency. This renders the patient susceptible to various opportunistic infections and neoplasms. Reactive oxygen intermediates (ROI) are important for the intracellular killing of microorganisms by mononuclear phagocytes and neutrophils. Although data are discrepant, several studies suggest that the generation of ROI is impaired in mononuclear phagocytes, and possibly also in neutrophils, from HIV-infected individuals. This may lead to deficient killing of intracellular microorganisms predisposing the HIV-infected patient to certain opportunistic infections. Recently, in vitro studies have shown that ROI activate the intracellular transcription factor nuclear factor kappa B (NF-kappa B) which stimulates HIV replication. Intracellular antioxidant systems, such as the glutathione system, seem to be of importance for the regulation of ROI levels and thus probably for HIV replication in vitro. However, the role of ROI in regulation of HIV replication in vivo is unknown at present. The role of ROI in HIV infection is thus difficult to assess, both at the cellular and clinical level. Reduced intracellular concentrations of ROI may lead to impaired phagocyte microbicidal functions, thus predisposing HIV-infected patients to various opportunistic infections. On the other hand, increased ROI levels may be associated with a stimulation of HIV replication leading to clinical deterioration.

Analysis of peripheral blood lymphocyte subsets in normal Saudi males by flow cytometry

Lymphocyte immunophenotyping using flow cytometer has become an important tool for clinical patient management as well as for research and epidemiological studies. We examined the distribution of CD3 (all T cells), CD4 (T helper/inducer cells), CD8 (T suppressor/totoxic cells), CD16 (natural killer cells) and CD19 (B cells) in 150 healthy Saudi male blood donors using flows cytometry. The two-color labeled cells were analyzed by using the flow cytometer (FACScan, Becton-Dickinson, San Jose, California, USA) and the dual fluorescent subsets were discriminated by Simultest software. The distribution of T lymphocytes, B lymphocytes, and natural killer (NK) cells were similar to those reported in other populations as well as in normal Caucasian expatriate donors (all males) (n = 40) who were included in this study as controls. However, a significantly decreased CD4/CD8 ratio was observed in most Saudi blood donors. These lower ratios were due to decreased CD4 together with an increase in CD8 cells. Significant (P<0.00001) difference in CD4/CD8 ratio in our study may be due to environmental factors such as ultraviolet radiation and stress (heat) as well as some genetic factors.

Phagocytosis and microbicidal capacity of human monocytes in the course of HIV infection

Phagocytosis and bactericidal activity of human monocytes were studied in asymptomatic HIV carriers and in patients with clinically apparent HIV infection, diagnosed as persistent generalised lymphadenopathy (PGL) or AIDS-related complex (ARC). Monocytes of asymptomatic HIV carriers manifested no significant changes while a decreased phagocytosis was shown by monocytes in the majority of patients with PGL or ARC. The latter patients also exhibited a decreased bactericidal activity of the cells. Tuftsin and even serum from healthy donors were found to normalise the disturbed monocyte function, the effect of tuftsin being more pronounced. Nevertheless, the examined sera contained neither factors which could stimulate nor factors which could inhibit phagocytosis. The obtained results indicated that the productive phase of HIV infection is associated with disturbed phagocytosis and disturbed microbicidal activity of monocytes, reflecting deficiency of serum factor(s) needed for the normal function of the cells.

Tuberculosis in HIV seropositive individuals--a retrospective analysis

A retrospective analysis of all culture-positive cases of Mycobacterium tuberculosis infection in HIV positive individuals, over a 5 year period, revealed 18 cases, drawn from a population of approximately 1500. The prevalence of culture proven M. tuberculosis over the 5 year period was therefore 1.2% and was strongly associated with either a concomitant, or a subsequent, AIDS diagnosis. Sixty-one per cent had pulmonary tuberculosis, 17% had both extra-pulmonary and pulmonary infection and 22% had extra-pulmonary infection alone. Although a wide range of radiological abnormalities was seen, segmental consolidation was the commonest, occurring in 57% of cases. Only 55% of the specimens were positive on initial stains for M. tuberculosis, with a mean duration of 4 weeks to become culture positive, emphasizing that early diagnosis rests on clinical suspicion.

Lack of HBV and HDV replicative activity in HBsAg-positive intravenous drug addicts with immune deficiency due to HIV

The effects of HIV infection on HBV and HDV replication and liver damage were evaluated by comparing the findings from 48 anti-HIV-positive HBsAg chronic carriers with those from 22 matched anti-HIV-negative subjects. The state of HBV/HDV infection was also related to the degree of immunodeficiency of the anti-HIV-positive patients. Most patients were intravenous drug addicts (IVDA) (84.2%); male homosexuals represented only a small proportion (7.1%). Serum HBV-DNA was detected more frequently in anti-HIV-negative than in anti-HIV-positive patients (50% vs. 35%) despite evidence of HDV replication in the anti-HIV-negative group (P = 0.02). Seroconversion from ongoing to inactive HBV infection occurred in 45% of anti-HIV-negative patients as well as in 23% of anti-HIV-positive patients (P = ns). The difference in severity of liver damage between the two groups was not statistically significant (P = 0.84). Furthermore, in the anti-HIV-positive subjects, HBV and/or HDV activity was detected in 63% of patients with mild immunodeficiency (CDC groups II and III with a total CD4 count greater than 400/mm3) and also in 75% of ARC-AIDS patients (CDC groups IV A-IV C) (P = ns). Severe hepatic disease occurred in subjects with CD4 counts above or below 400/mm3 (13 vs. 6, respectively). In conclusion, the data do not demonstrate that HBV or HDV infections are modified by HIV. The epidemiological background of the patients investigated and the extensive spread of hepatitis viruses in Italy before the appearance of HIV may account for the lack of relationship between HIV and HBV/HDV infections.

Association of circulating receptor Fc gamma RIII-positive monocytes in AIDS patients with elevated levels of transforming growth factor-beta

Monocytes in the circulation of normal individuals express two receptors for the constant region of immunoglobulin, Fc gamma RI and Fc gamma RII. In contrast, we have observed that AIDS monocytes express significant levels of a third Fc gamma R, Fc gamma RIII (CD16), which is normally associated with activation or maturation of the monocyte population. By dual-fluorescence analysis using a monoclonal antibody specific for Fc gamma RIII (MAb 3G8), 38.5 +/- 3.2% of the LeuM3 (CD14)-positive monocytes in AIDS patients were CD16 positive as compared to 10.4 +/- 1.0% for healthy individuals (n = 29; P less than 0.005). Furthermore, AIDS monocytes expressed Fc gamma RIII-specific mRNA which is expressed minimally or not at all in control monocytes. As a recently identified inducer of Fc gamma RIII expression on blood monocytes, transforming growth factor-beta (TGF-beta) was found to be elevated in the serum and/or plasma of AIDS patients. Moreover, incubation of normal monocytes with AIDS serum or plasma induced CD16 expression which correlated with serum TGF-beta levels (r = 0.74, P less than 0.001) and was inhibited with a neutralizing antibody to TGF-beta. Thus, the increased CD16 expression on peripheral blood monocytes in AIDS patients may be the consequence of elevated circulating levels of the polypeptide hormone TGF-beta.

Alveolar macrophages in AIDS patients: increased spontaneous tumour necrosis factor-alpha production in Pneumocystis carinii pneumonia

In order to assess the role of alveolar macrophages and their products in the control of Pneumocystis carinii pneumonia (PCP) and other infections in AIDS, bronchoalveolar lavage cells and peripheral blood mononuclear cells from HIV-positive AIDS/ARC patients (with and without PCP) and HIV-negative patients were counted and cultured in vitro; spontaneous and LPS-induced tumour necrosis factor-alpha (TNF-alpha) production was measured. Markedly increased spontaneous TNF-alpha production by alveolar macrophages and, to a lesser extent, peripheral blood monocytes was found in HIV-positive patients with active PCP but not in patients without the infection. Higher TNF production was associated with lower counts of Pneumocystis in the bronchoalveolar lavage fluid. These results suggest that TNF-alpha production by macrophages may play an important role in the control of Pn. carinii infection in AIDS.

Coping with change in the NHS: a frontline district's response to AIDS

The core of this paper is a case study of how a District Health Authority (Paddington and North Kensington, now Parkside DHA following a recent merger with Brent DHA) in Inner London responded to a major new health care issue of the 1980s--Aids, but the paper also seeks to locate this case study material within wider debates. What theories are there of organisational change which could be used to illuminate policy and service change in the health care sector? How, indeed, do we best study change in health care organisations? The paper is thus in three parts. In the first section we identify some streams of literature which act as a frame of reference defining our initial research question and discuss implications for methodology. The second section presents the case itself, while the last section discusses some emerging findings.

Mycobacterial infection in patients infected with the human immunodeficiency virus

Of 207 homosexual or bisexual patients with the acquired immune deficiency syndrome (AIDS), 24 with the AIDS related complex, and 39 with asymptomatic HIV infection, 32 patients were found to have mycobacterial infection. Mycobacterium tuberculosis was found in 13 patients with AIDS and in two with the AIDS related complex. M avium-intracellulare was found in 15 patients with AIDS and was disseminated in 12. One patient was infected with M kansasii and one with M ulcerans. Invasive procedures were frequently required to obtain positive bacteriological results. Subclinical carriage of M avium-intracellulare and other mycobacteria thought to be nonpathogenic was common in patients seronegative for the human immunodeficiency virus and at all stages of human immunodeficiency virus infection. All but one isolate of M tuberculosis were fully sensitive to standard antimycobacterial antibiotics. Response to treatment was usually rapid. M avium-intracellulare isolates were all resistant to first line agents in vitro, and antibiotics such as ansamycin and amikacin were required to obtain a clinical response.

Inverted T helper/T suppressor lymphocyte ratio is not a reliable indicator of coexistent HIV infection in the presence of carcinoma: report of a patient with ovarian carcinoma and inverted TH/TS ratio

Patients with non-HIV (Human Immunodeficiency Virus) related cancers may also have HIV infection. Inverted peripheral blood lymphocyte T helper/T suppressor ratios with selective loss of T helper cells may be used as a clinical screening test for HIV infection in these patients since they may be seronegative for retrovirus infection early in the course of infection. We describe a case in which carcinoma alone appeared to induce systemic changes that resembled coexistent HIV infection. Many of these abnormalities, including inverted TH/TS ratio with selective loss of T helper cells, improved in the immediate postoperative period, indicating that HIV infection was not present. We conclude then, that diagnosis of HIV infection should not be made without more definitive evidence of its presence than an inverted TH/TS ratio in a patient with carcinoma.

T lymphocyte subsets and viral infections in Sardinian parenteral drug abusers: relationship to HIV infection

To investigate whether the human immunodeficiency virus (HIV) infection or the abuse of narcotic drugs or other viral infections may be responsible for immunologic abnormalities in parenteral drug abusers, sera from 168 consecutive individual patients were collected from 1985 to 1986. The sera were tested for antibody to HIV (anti-HIV), and the clinical, immunologic, and serologic characteristics of 83 seropositive and 53 seronegative parenteral drug abusers were compared. The presence of anti-HIV was significantly associated with a decreased number of T helper lymphocytes (P less than .001), a reduced T helper/suppressor ratio (P less than .001). Of the 83 seropositive patients, 63 (76%) had generalized lymphadenopathy and 16 (18%) had AIDS-related complex. No patient had AIDS. Parenteral drug abusers with AIDS-related complex had significant reductions in the number of T helper cells (P less than .01) and the T helper/suppressor ratio (P less than .01) compared with patients with lymphadenopathy syndrome (LAS), suggesting that parenteral drug abusers with HIV infection develop a progressive immunodeficiency. IgG antibody to cytomegalovirus was found in 75% of anti-HIV-positive and 45% of anti-HIV-negative parenteral drug abusers (P less than .01), but significant associations between anti-HIV and markers for other viruses were not found. Our data confirm that HIV infection is the major cause of low T helper cells and reversed T helper/suppressor ratio in parenteral drug abusers.(ABSTRACT TRUNCATED AT 250 WORDS)

Seroepidemiologic studies on the acquisition of antibodies to cytomegalovirus, herpes simplex virus, and human immunodeficiency virus among general hospital patients and those attending a clinic for sexually transmitted diseases

A total of 731 sera were collected from general hospital patients, divided into five distinct subgroups, and tested for the presence of immunoglobulin (IgG) to cytomegalovirus (CMV) and herpes simplex virus (HSV). The results indicate a high level of association between the two viruses, although HSV was found to be more prevalent in the earlier years of life, whereas CMV was acquired constantly throughout life. An increase in age was also accompanied by significantly higher antibody levels to both viruses. Individuals with antibody to HSV were significantly more likely to have antibodies to CMV, suggesting that these viruses are transmitted by similar routes (?saliva). In addition, 430 sera from 94 homosexual and 336 heterosexual males attending a clinic for sexually transmitted diseases were tested for antibody to CMV, HSV, and human immunodeficiency virus (HIV). Homosexual males were more likely to have antibody to CMV and HIV than were heterosexuals, but no difference was seen for HSV antibodies. The levels of CMV-specific IgG were significantly raised in homosexuals, compared with heterosexuals, but again no difference was seen for HSV antibodies as in the general hospital patients, however, individuals with HSV antibodies were significantly more likely to possess antibodies to CMV. However, the additional association of CMV antibodies with a homosexual lifestyle suggests that an alternative route for acquisition of this virus exists (?semen). As raised levels of CMV antibodies, but not HSV antibodies, were found among homosexuals, this suggests that frequent CMV reinfections, rather than merely reactivation of latent herpes viruses, may be occurring.

Abnormal antibody responses in patients with persistent generalized lymphadenopathy

Persistent, generalized lymphadenopathy (PGL) is a recognized component of human immunodeficiency virus (HIV) infection. We conducted longitudinal studies of B and T cell function in seven homosexual men with HIV infection and PGL. All seven had abnormal antibody-mediated immunity as studied by sequential assessment of in vivo antibody responses after immunization with the T-dependent neoantigens bacteriophage phi X 174 and keyhole limpet hemocyanin (KLH), the T-independent tetradecavalent pneumococcal polysaccharide vaccine, and the recall antigens diphtheria and tetanus toxoid. Compared to HIV-negative heterosexual controls, PGL patients responded with lower antibody titers and, following immunization with phage, failed to develop immunologic memory and to switch from IgM- to IgG-isotype antibody. In vitro antigen-induced antibody production was markedly diminished; and some patients showed depressed mitogen responses. There was a correlation between the degree of compromised immunity and the clinical condition; those with the most severe symptoms showed the most extensive immune deficiency. Yet despite obvious immunologic impairment five of the seven men have remained clinically stable over a 3-year follow-up period.

Monocyte phenotype and function in patients with the acquired immunodeficiency syndrome (AIDS) and AIDS-related disorders

The CD4 molecule, which is known to play an important role in the susceptibility of T lymphocytes to infection by the human immunodeficiency virus (HIV), is also expressed in small amounts on the surface of monocytes. Since monocytes can also be infected by the virus, we investigated peripheral blood monocytes of patients with the acquired immunodeficiency syndrome (AIDS), AIDS-related complex (ARC), and HIV seropositive and seronegative haemophiliacs without symptoms for the expression of the CD4 molecule and for other functionally important surface molecules such as CD11 (C3bi receptor), transferrin receptor, Fc receptor, and the three major histocompatibility complex (MHC) class II antigens HLA-DP, HLA-DR, and HLA-DQ. With immunofluorescence staining and flow cytometry no difference was found between patients and controls for the expression of the CD4 molecule and for the other antigens as assessed by the percentage of positive staining and the specific fluorescence intensity in a double marker analysis. The percentage of CD4+ monocytes was found to be 59.2 +/- 14.4% for 16 patients with AIDS and 52.9 +/- 12.8% for 12 healthy controls. Similar to our results on phenotype, we found no significant difference with respect to the production of tumour necrosis factor (TNF), in that monocytes of AIDS and ARC patients showed an increase in TNF secretion after stimulation with LPS comparable to controls.

Association of different allelic forms of group specific component with susceptibility to and clinical manifestation of human immunodeficiency virus infection

The distribution of phenotypes of the group specific component (Gc) was examined in 203 homosexuals at risk of infection or infected by the human immunodeficiency virus and compared with that in 50 randomly selected homosexuals and 122 healthy male heterosexual seronegative controls. 30.2% of patients with the acquired immunodeficiency syndrome (AIDS) were homozygous for Gc 1 fast (Gc 1f) compared with 0.8% of controls (p less than 0.0001); patients with other clinical manifestations of HIV infection were also more likely than controls to have Gc 1f. By contrast, seronegative symptomless homosexual contacts of AIDS patients (AH-p) lacked this phenotype but were more likely than controls to be homozygous for Gc 2 (25% vs 9%, p less than 0.05). AIDS patients lacked the homozygous Gc 2 phenotype altogether. A chi 2 trend test showed that progression to AIDS had a strong positive association with the Gc 1f allele (p less than 0.0001) and a negative one with Gc 2 (p less than 0.05). It is proposed that Gc may be involved in viral entry into host cells, the ease of which varies with different allelic forms of Gc, according to their sialic acid content.

Cytomegalovirus infection in homosexual men. Relationship to sexual practices, antibody to human immunodeficiency virus, and cell-mediated immunity

To investigate the relationships among cytomegalovirus infection, sexual behavior, human immunodeficiency virus (HIV) seropositivity, and indexes of cellular immunity, 180 homosexual men and 26 heterosexual men were studied. Among the homosexual men, cytomegalovirus seropositivity was associated with increased T8 lymphocyte counts (p less than 0.001) and reduced T4/T8 ratios (p = 0.006); these results were independent of HIV infection. Cytomegalovirus seropositivity was also associated with increasing age, numbers of sexual partners, and the practice of anal-receptive intercourse. At the first visit, cytomegalovirus was isolated from none of 13 cytomegalovirus-seropositive heterosexual subjects, compared with 62 (36 percent) of 171 seropositive homosexual men (p less than 0.005). Viral isolation was most common from semen. Among 32 cytomegalovirus-seropositive homosexual subjects from whom culture specimens were obtained more than four times over 10 to 30 months, 72 percent of the specimens were culture-positive. The mean duration of cytomegalovirus excretion in semen was 22 months, and in urine, the duration was nine months. Cytomegalovirus excretion was associated with younger age and reduced lymphocyte proliferation in response to cytomegalovirus, but not with antibody to HIV. Cytomegalovirus infection is sexually transmitted among homosexual men, perhaps by rectal intercourse, and is associated with alterations in T lymphocyte subsets. Most seropositive homosexual men excrete cytomegalovirus intermittently, primarily in the semen.

Demonstration of defective C3-receptor-mediated clearance by the reticuloendothelial system in patients with acquired immunodeficiency syndrome

The function of macrophage C3 receptors was assessed in vivo by measuring the clearance of C3-sensitized autologous erythrocytes in seven acquired immunodeficiency syndrome (AIDS) patients, eight healthy homosexual men, eight healthy heterosexual men, and four infected controls. Healthy heterosexual men had an initial clearance of 50.1 +/- 2.0% of the inoculum, with a release of a small portion of these cells (10.9 +/- 1.3%) into the circulation. Healthy homosexual men had a greater initial clearance of 66.0 +/- 4.2% (P less than 0.01) followed by a similar release (14.0 +/- 3.3%). AIDS patients had an initial clearance of 60.6 +/- 7.5% but had a relatively large release of cells (25.6 +/- 3.2%) (P less than 0.005 vs. heterosexuals; P less than 0.05 vs. homosexuals), suggesting a failure of macrophage phagocytosis. Infected controls had an initial clearance of 59.4 +/- 4.9%, with a release of 19.6 +/- 3.8% (P = NS vs. AIDS). These data, in addition to Fc-receptor dysfunction, demonstrate a global reticuloendothelial system dysfunction in AIDS patients. This may contribute to their frequent infections with opportunistic pathogens and inappropriate immune responses against these microorganisms.

Infection with human immunodeficiency virus (HIV) and cytomegalovirus in a London health district 1980-4

By testing serum samples taken between 1980 and 1984 from men attending a department of sexually transmitted diseases, it was shown that antibodies to human immunodeficiency virus (HIV) first appeared in 1981. Homosexual men were significantly more likely to have antibodies to HIV and to cytomegalovirus (CMV) than were heterosexual men attending the same clinic. This shows that homosexuals are exposed to both HIV, the cause of the acquired immune deficiency syndrome (AIDS), and to CMV, which can reactivate to cause life threatening disease once immunosuppression has developed. All homosexuals, not just those with antibodies against HIV, had raised levels of CMV antibodies. This suggests that they experience frequent antigenic stimulation after reinfections with CMV or reactivation of endogenous virus.

Controlled clinical trial of acyclovir in chronic hepatitis B virus infection

A randomised, controlled trial comparing acyclovir, 45 mg/kg/day as a continuous IV infusion for 28 days, with no other therapy, was carried out in 30 stable HBsAg carriers seropositive for HBeAg for more than 6 months. Twenty-eight had hepatitis B virus DNA-polymerase activity and/or hepatitis B virus DNA in serum at entry into the study. There were no significant adverse effects of therapy. At 12 months, seroconversion from HBeAg to anti-HBe had occurred in four of 15 treated patients, one of whom had also developed anti-HBs, compared with only one of 15 in the untreated group (95% confidence limits 12% and 51%). Seroconversion from HBeAg to anti-HBe was accompanied by return of serum liver function tests to normal and improved liver histology. The results of this study indicate that acyclovir is of no significant benefit in chronic HBeAg carriers with stable disease.

Screening for HIV infection: risks, benefits, and the burden of proof

In 1984, scientists isolated a new pathogen, now called human immunodeficiency virus (HIV), that is almost certainly the etiological agent for the acquired immunodeficiency syndrome (AIDS). It has been estimated that there are between 500,000 and 1,750,000 asymptomatic, chronically HIV-infected individuals in the United States. In a remarkably short time, investigators developed a number of blood tests that indicate whether an individual is likely to be infected with this virus. These assays are now being used to test patients with symptoms suggesting AIDS or related syndromes, to screen donated blood, to evaluate individuals concerned about their infection status, and to screen new military recruits, active-duty soldiers, and ROTC students. Almost weekly, new proposals are advanced for screening different subsets of the population.

Intradermal testing with multiple recall antigens for identification of cell-mediated immune deficiency in homosexual men

In a health screening project for gay men in Stockholm, delayed cutaneous hypersensitivity was tested in 710 men by a commercial kit (Multitest, Mérieux) containing seven recall antigens and related to past hepatitis B virus (HBV) infection, various life style factors, the lymphadenopathy syndrome (LAS), and antibodies to human T-lymphotropic virus type III (HTLV-III). The multiscore (MS: the sum of all positive reactions) was significantly decreased in men with the following characteristics: HBV markers, greater than 50 yearly sexual partners, regular practice of receptive rectal intercourse, regular sex in gay bathhouses, recent sexual encounters in the US, greater than 50 lifetime exposures to inhaled nitrates, LAS, and positive HTLV-III serology. Anergy to tuberculin (TU) but not to any other antigen was more common in men with greater than 20 yearly partners, regular practice of receptive rectal intercourse, exposure to inhalant nitrates, LAS as well as lesser degree of lymphadenopathy, and HTLV-III seropositivity. HTLV-III antibodies were demonstrated in 61 of 416 (14.7%) men. During the 2-year follow-up four men have developed acquired immune deficiency syndrome. All four had MS less than 10 mm and TU anergy. In a BCG-immunized population Multitest only adds marginal information as compared to intradermal testing solely with TU, but may yield prognostic information in evaluating HTLV-III positive individuals with respect to development of manifest AIDS.

Abnormality of Leu 2+7+ cells in acquired immune deficiency syndrome (AIDS), AIDS-related complex, and asymptomatic homosexuals

Peripheral blood mononuclear cells from patients with acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC), asymptomatic homosexuals, and healthy heterosexuals were analyzed for the proportions and numbers of Leu 7+ cells and double-labeled Leu 2+7+ cells and for the natural killer functions. A significant increase in the proportions and numbers of Leu 7+ cells was observed in patients with AIDS and ARC and in asymptomatic homosexuals compared to healthy heterosexual men. The proportions of Leu 2+7+ cells were significantly increased in AIDS, ARC, and asymptomatic homosexuals, whereas the numbers were increased in asymptomatic homosexuals and ARC but not in AIDS compared to heterosexual controls. A significant increase in the number of Leu 2+7+ cells was observed in AIDS with Kaposi's sarcoma but not in AIDS with opportunistic infections. The natural killer function was significantly depressed in patients with AIDS and ARC and in asymptomatic homosexuals. These data suggest that the quantitative abnormalities of Leu 2+7+ cells appear early during the evolution of immunologic changes in HTLV III/LAV infection.

Normal T cell subsets in homosexual men living in a community without endemic AIDS

The cause of the abnormal T lymphocyte subsets reported in healthy homosexual men is not known. Frequent sexually transmitted infections including human T cell lymphotropic virus type III/lymphadenopathy-associated virus (HTLV-III/LAV) are possible causes. To determine if the T lymphocyte subsets were abnormal in this population in an area without endemic acquired immune deficiency syndrome (AIDS), T lymphocyte subsets of 52 homosexual men in Rochester, New York, were enumerated, and evidence of infections known to cause these abnormalities was sought. Unlike the findings in previous reports, relative numbers of T helper and T suppressor cells and helper/suppressor T cell ratios were normal. Prevalence of cytomegalovirus infection (86 percent) was similar to that found in analogous populations, but only 9 percent had seropositive results for HTLV-III/LAV. Men with serologic evidence of nonprimary cytomegalovirus disease had lower helper/suppressor T cell ratios (1.5 +/- 0.2 versus 2.2 +/- 0.2; p less than 0.01). Hence, despite frequent infections with cytomegalovirus and other sexually transmitted pathogens, T cell subsets are normal in homosexual men in an area without endemic AIDS. Therefore, HTLV-III/LAV is primarily responsible for the T cell abnormalities observed elsewhere.

Early defect of phagocytic cell function in subjects at risk for acquired immunodeficiency syndrome

We studied the functions of peripheral blood monocytes and polymorphonuclear cells in 15 apparently healthy homosexual men, eight homosexual or bisexual subjects with unexplained generalized lymphadenopathies (pre-AIDS), four homosexual men with acquired immunodeficiency syndrome (AIDS), and 15 heterosexual men. In comparison with normal controls, the homosexual groups studied presented a decreased monocyte candidacidal activity for Candida pseudotropicalis that gradually deteriorates as the clinical symptoms progress towards AIDS. The monocyte phagocytic function was retained. Although the phagocytic and candidacidal activities of the polymorphonuclear cells did not differ from those of the normal controls, the candidacidal activity in some of the cases studied was unusually enhanced, indicating that the cells were in an activated state. In addition, only two of nine sera tested from asymptomatic homosexual males were positive for antibodies to HTLV-III/LAV, while six out of eight pre-AIDS and both of the two AIDS patients tested had antibodies to AIDS-associated retrovirus. We suggest that in AIDS the phagocytic system is already involved, together with B and T lymphocyte abnormalities, during the early events of the syndrome, even without the detection of AIDS-associated retrovirus antibodies.

Altered functions of peripheral blood monocytes in homosexual males and intravenous drug users with persistent generalized lymphadenopathy

Persistent generalized lymphadenopathy (PGL) is observed predominantly in subjects at risk of developing AIDS. Twenty-seven individuals belonging to such groups: twelve homosexual males and fifteen intravenous drug users, were investigated for immunological abnormalities with particular attention to monocyte functions. They were compared with five AIDS patients. Twenty out of twenty-two individuals had anti-LAV/HTLV-III antibodies and most had abnormalities characteristic of AIDS: polyclonal hypergammaglobulinemia, decreased cell-mediated immunity, inverted T-cell helper/suppressor ratio and histological alterations of lymph nodes. As for peripheral blood monocyte functions, phagocytic capacity and production of O2- were normal and bactericidal capacity was decreased. Monocytes cultured in the presence of concanavalin A produced less PGE2 and more IL-1/MCF than normal monocytes. Similar abnormalities were found using monocytes from AIDS patients. These data suggest that monocytes from patients with PGL have functional alterations that may be either intrinsic or secondary to lymphocyte dysfunction(s); these alterations do not account for the decreased capacity of lymphocytes to respond to mitogens but may explain the uncontrolled activation of B cells.

Three-year prospective study of HTLV-III/LAV infection in homosexual men

170 symptom-free homosexual men were recruited in London in 1982-83 and 133 were evaluable in 1983-85. Of the 33 who were seropositive to HTLV-III/LAV at entry, 4 (12%) progressed to AIDS, 16 (48%) progressed to persistent generalised lymphadenopathy (PGL), and 13 (40%) remained symptom-free. A further 15 men seroconverted during the study (7% per annum), of whom 8 progressed to PGL. Serial estimations of T lymphocyte subsets showed progressive reduction in T4 numbers in the seropositive groups, but these indices also varied widely in the seronegative group. Counts of T4 and T8 cells or T4/T8 ratio at entry were not of prognostic value. Seronegative subjects were as likely as seropositives to have abnormal immunological tests. Serial measurement of T lymphocyte subsets seems to be of little prognostic or clinical value in the monitoring of populations infected with the HTLV-III/LAV virus. The strongest association with prognosis was an episode of sexually transmitted disease in the six months before entry to the study. This supports the hypothesis that intercurrent infection may be an important co-factor in the acquisition of HTLV-III/LAV infection, and in subsequent disease progression.

Clinical approach to viral hepatitis in homosexual men

The prevalence of both hepatitis A and hepatitis B is increased in homosexual men. On an annual basis, 5% to 7% of homosexual men will acquire hepatitis A. Risk factors for HAV infection include length of homosexual activity, number of sexual contacts, and oral--anal sexual contact. The HBsAg carrier rate of homosexual men is 5% to 6%, and another 50% have evidence of previous HBV infection with a positive anti-HBs. HBeAg is present in a higher precentage of HBsAg-positive homosexual men (38% to 75%) than in general population carriers (3% to 30%). The annual incidence for HBV infection in homosexual men is 16% to 28%, higher than that for hepatitis A. Transmission of HBV infection in homosexual men is facilitated by a large number of sexual partners, high HBsAg carrier rate, high infectivity of carriers (positive HBeAg), and the specific sexual practices of oral--anal and anal--genital contact with exposure to HBV on open mucosal surfaces. The prevalence of non-A, non-B and delta infection in homosexual men is probably somewhat increased, but the importance of these viruses in the development of hepatitis in this population remains uncertain. Prevention of hepatitis A and B in homosexual men will ultimately be achieved by vaccination of susceptible individuals, which currently is feasible only for hepatitis B. Appropriate use of immune globulins for postexposure prophylaxis and knowledge of specific sexual practices that transmit disease may reduce the incidence of hepatitis A and B.

Immunologic aspects of the acquired immunodeficiency syndrome and male homosexuality

The acquired immunodeficiency syndrome (AIDS) is the most common and best characterized disorder of T cells leading to enhanced susceptibility to infection. Current hypotheses hold that infection with human T-cell lymphotropic virus type III/lymphadenopathy virus (HTLV-III/LAV) is a necessary but not a sufficient condition for the development of AIDS, and that a variety of cofactors participate in the pathogenesis of the syndrome. This article reviews the immunologic aspects of AIDS and the AIDS-related syndromes, as well as concepts of etiology and pathogenesis. Predisposing factors for this disease in the homosexual or bisexual host are emphasized.

Flow cytometric analysis of lymphocyte phenotypes in AIDS using monoclonal antibodies and simultaneous dual immunofluorescence

Simultaneous dual immunofluorescence and flow cytometry was used to study sixteen lymphocyte phenotypes in 209 men including: healthy homosexuals, lymphadenopathy patients (LAN), and AIDS patients. Significant differences between the distribution of lymphocytes in healthy homosexuals and healthy heterosexuals were decreased percentages of helper/inducer T cells (Leu 3), increased cytotoxic/suppressor T cells (Leu 2), and consequently a decreased Leu 3/Leu 2 ratio. The increased Leu 2 cells were identified as functionally cytotoxic subset Leu 2+ 15- phenotype rather than suppressor cells which are Leu 15+. Leu 2 and Leu 3 bearing cells exhibited an excess of membrane-bound immunoglobulins which were easily elutable at 37 degrees C. An increased percentage of an HLA-DR framework determinant bearing T cells were also detected. Within the NK cell family, Leu 7 cells were moderately increased and the functionally unidentified Leu 2+ 7+ population was strikingly elevated. LAN or AIDS patients were compared to healthy homosexual controls. Lower percentages of Leu 3 cells and higher percentages of Leu 2 cells were evident in LAN patients. These subsets were similar in LAN and AIDS patients. The increase in Leu 2+ cells was due to the Leu 2+ 15- cytotoxic subset. Fewer T cells had immunoglobulin in LAN and AIDS. A definite increase in Leu 2+ DR+ cells but not Leu 3+ DR+ cells occurred in AIDS compared to LAN or healthy controls. NK cell changes already present in healthy homosexuals persisted in LAN and AIDS patients. No differences in the distribution of B cells was detected in any intergroup comparisons. Changes in monocytes or pan-T cells were relatively insensitive measures of immunologic alterations among any of the groups. These results indicate many of the changes in lymphocyte subsets seen in AIDS and LAN subjects are already present in a carefully screened population of healthy homosexuals in San Francisco. Many of the changes in Leu 2 and NK family of cells suggest a possible adaptive response to viral or neoplastic challenge. Whether these interesting phenotypic alterations relate to functional changes in response to such challenge of the identified subsets waits further investigation.

Lymphocyte subpopulations in Spanish parenteral drug addicts

Lymphocyte subpopulations were studied in 29 symptom-free Spanish prisoners who were active parenteral drug abusers. In 16/29 drug addicts (55%) the helper-inducer/suppressor-cytotoxic ratio (Leu 3a/Leu 2a) was less than 1. None of these 16 patients had lymphopenia and only 2 had a reduction in the number of Leu 3a cells. In drug addicts the number of lymphocytes (p less than 0.01) and the number and percentage of Leu 2a cells (p less than 0.001) were significantly raised. The addicts also had a higher absolute number of T cells when measured by their ability to react with the Leu 4 antibody (p less than 0.01). However, the E-rosette forming cells were significantly reduced. Thus the E-rosette test may lead to an overestimation of "null" cells. Furthermore drug addicts had a higher percentage (p less than 0.001) of Leu 7 positive cells (NK and K cells), but a normal percentage of B and phagocytic cells. Five drug addicts had generalized persistent lymphadenopathies, and 2 had skin anergy. We believe that most of the immunologic abnormalities seen in these apparently healthy drug abusers can be explained by an antigenic overload.

Influence of sexual preference and chronic hepatitis B virus infection on T lymphocyte subsets, natural killer activity, and suppressor cell activity

To determine whether abnormalities of cell-mediated immunity are associated with chronic hepatitis B virus infection or with homosexuality, we studied 15 homo- and 11 heterosexual men with chronic hepatitis B virus infection, as well as 11 homo- and 16 heterosexual apparently healthy men. T lymphocyte subsets, natural killer activity, and suppressor cell activity were determined. Homosexual men had significantly lower peripheral blood T4/T8 ratios resulting from a significant increase in T8-positive (suppressor/cytotoxic) cells, and they also had lower natural killer activity. These effects of homosexuality were independent of chronic hepatitis B virus infection, which caused no significant changes independent of homosexuality, and they were not caused by infection with human immunodeficiency virus (formerly HTLV-III/LAV). Suppressor cell function was unaltered in this study. We conclude that studies of cellular immunity in hepatitis B virus infection must take male sexual preference into account.