The uptake of a labeled double-stranded polynucleotide by cultured rabbit kidney cells: an electron microscopic study

Polyribocytidylate-³H-polyriboinosinate (rC-³H:rI) enters cultured rabbit kidney cells from the surrounding medium within ½ hr after exposure. Grains are found in the cytoplasm, nucleus, and nucleolus. At 2 hr, grains are localized predominantly over the nucleolar regions. Subsequently, the grains in the nucleus become dispersed. A specific receptor site for the initiation of interferon production was not revealed.

Prevalence of HTLV-I-associated T-cell lymphoma

In order to assess the prevalence rate of HTLV-1-associated T-cell lymphomas and human retrovirus infection in general, approximately 21,000 individuals representing various patient populations, retroviral risk groups, and blood donors were examined for HTLV-I, HTLV-II, HIV-1, or HIV-2 infection using serologic and PCR assays. The prevalence rates among volunteer blood donors were 0.02% and 0% for HTLV and HIV, respectively. Significantly increased HTLV prevalence rates were observed among paid blood donors, African American health care clinic patients, Amerindians, recipients of HTLV-positive cellular blood products, intravenous drug users, sexual contacts and family members of HTLV-positive people, and patients with primary thrombocytosis and other-than-low-grade non-Hodgkin's lymphoma (NHL). Among some of these groups there were significant differences in the prevalence of HTLV-I versus HTLV-II. The eight HTLV-positive NHL patients all had mature, high-grade, CD4+ T-cell lymphomas with clonally integrated HTLV-I, for a prevalence of 4% among other-than-low-grade NHL patients. Seven of the eight died from their disease within 2 years despite treatment. Interestingly, two groups at risk for HTLV infection, namely needle stick victims and recipients of HTLV-infected and/or pooled plasma products, showed no evidence for infection. Significantly increased HIV-1 prevalence was observed among paid blood donors, African Americans, homosexuals, female prostitutes, hemophiliacs, and other-than-low-grade NHL patients. Only one patient was infected with HIV-2. Of the nine HIV-positive, other-than-low-grade NHL patients, seven HIV-1 positives had B-cell lymphomas, one HIV-1 positive had an HTLV-I-positive CD4+ T-cell lymphoma, and one infected with HIV-2 had a CD4+ T-cell lymphoma that was HTLV negative. The data indicate that HTLV-I lymphoma, while uncommon, is not necessarily rare among other-than-low-grade NHL cases in the United States and, given its poor prognosis, should probably be studied separately in clinical trials.

Pegylated-liposomal doxorubicin versus doxorubicin, bleomycin, and vincristine in the treatment of AIDS-related Kaposi's sarcoma: results of a randomized phase III clinical trial

PURPOSE

Kaposi's sarcoma (KS), the most common neoplasm in patients with AIDS, is a significant clinical problem for which current therapies are frequently unsatisfactory. We conducted a randomized phase III clinical trial to compare the efficacy and toxicities of a new form of therapy, pegylated-liposomal doxorubicin, with standard combination chemotherapy in patients with advanced AIDS-related KS (AIDS-KS).

PATIENTS AND METHODS

Two hundred fifty-eight patients with advanced AIDS-KS were randomly assigned to receive either pegylated-liposomal doxorubicin (20 mg/m2) or the combination of doxorubicin (20 mg/m2), bleomycin (10 mg/m2) and vincristine (1 mg) (ABV) every 14 days for six cycles. Standard response criteria, toxicity criteria, and predefined indicators of clinical benefit were examined to evaluate outcomes.

RESULTS

Among 133 patients randomized to receive pegylated-liposomal doxorubicin, one achieved a complete clinical response and 60 achieved a partial response for an overall response rate of 45.9% (95% confidence interval [CI], 37% to 54%). Among 125 patients randomized to receive ABV, 31 achieved a partial response (24.8%; 95% confidence interval [CI], 17% to 32%). This difference was statistically significant (P < .001). In addition to objective responses, prospectively defined clinical benefits and toxicity outcomes also favored pegylated-liposomal doxorubicin.

CONCLUSION

Pegylated-liposomal doxorubicin is more effective and less toxic than the standard combination chemotherapy regimen ABV for treatment of AIDS-KS.

Detection and titration of human herpesvirus-8-specific antibodies in sera from blood donors, acquired immunodeficiency syndrome patients, and Kaposi's sarcoma patients using a whole virus enzyme-linked immunosorbent assay

A human herpesvirus-8 (HHV-8) enzyme-linked immunosorbent assay (ELISA) with a whole virus lysate as antigen was developed and used to measure the seroprevalence rate and levels of IgG antibodies to HHV-8 in sera/plasma of various patient groups and blood donors. The virus antigen was prepared from the KS-1 cell line, which produces lytic virus, and therefore contains a broad array of viral proteins. Seroprevalence studies using this ELISA showed the following: 10 of 91 blood donors (11%) had an average HHV-8 antibody titer of 118; 67 of 72 (93%) classic Kaposi's sarcoma (KS) patients were positive with an average titer of 14,111; and 57 of 62 (92%) KS/human immunodeficiency virus (HIV) patients were positive with an average titer of 4,000. A study on a very limited number of serial serum samples from patients before and after diagnosis with KS showed highly elevated antibody titers to HHV-8 virus after KS lesions developed. Preliminary data show that 50% of the sera from HIV-1(+) homosexual patients contain IgG antibodies to HHV-8 suggesting that this population is at high risk for developing KS. Antibody results correlated well with the confirmatory immunofluorescent assays (IFA) using KS-1 cells as the substrate. This HHV-8 IgG antibody detection ELISA is sensitive and specific and does not cross-react with Epstein-Barr virus (EBV) or other human herpesviruses. The results of this HHV-8 antibody survey suggest that this rapid ELISA assay can be used to screen large numbers of sera to find those at risk for developing KS.

Pulsed dye laser treatment of molluscum contagiosum in a patient with acquired immunodeficiency syndrome

BACKGROUND

Molluscum contagiosum is usually a self-limited benign viral disease in children and young adults. In patients with acquired immunodeficiency syndrome (AIDS), however, the infection is often widespread, disfiguring, and recalcitrant to conventional therapy.

OBJECTIVE

A treatment modality for widespread, recurrent molluscum contagiosum is necessary that is effective, safe, and simple.

METHODS

Widespread molluscum contagiosum recalcitrant to conventional therapy in a patient with AIDS was treated with the 585-nm pulsed dye laser.

RESULTS

There was a significant reduction in the number of molluscum contagiosum lesions following a single treatment with the pulsed dye laser. Treated-areas remained disease-free after 4 months. No complications were associated with the procedure.

CONCLUSION

Pulsed dye laser treatment may offer another therapeutic modality that is effective and safe in the treatment of widespread and recurrent molluscum contagiosum.

Absence of human herpes virus 8 DNA sequences in large granular lymphocyte (LGL) leukemia

The etiology of large granular lymphocyte (LGL) leukemia is uncertain. Recently, a Kaposi's sarcoma-associated herpes virus, denoted as human herpes virus 8 (HHV-8), has been identified. Some data suggest that HHV-8 and Epstein-Barr virus (EBV) may interact to induce malignant transformation. Infection with EBV has been implicated in the pathogenesis of some cases of LGL leukemia. Therefore, we performed PCR analyses for HHV-8 detection in samples from nineteen patients with LGL leukemia; three of these samples contained the EBV genome. We could not detect HHV-8 sequences in any of these patients. Therefore, HHV-8 infection is not involved in the pathogenesis of T-LGL leukemia.

Management of acyclovir-resistant herpes simplex and varicella-zoster virus infections

Persons with AIDS who have CD4+ counts < or = 100 and transplant patients, especially bone marrow allograft recipients, may experience clinically significant infections with acyclovir-resistant herpes simplex virus (HSV) or varicella-zoster virus (VZV). Patients who have received prior repeated acyclovir treatment appear to be at the highest risk of harboring acyclovir-resistant strains. Algorithms for the management of these infections were developed at a recent roundtable symposium. The consensus of the panelists was that treatment with foscarnet should be initiated within 7-10 days in patients suspected to have acyclovir-resistant HSV or VZV infections. Foscarnet therapy should be continued for at least 10 days or until lesions are completely healed.

Prognostic factors and staging classification of patients with epidemic Kaposi's sarcoma

Two hundred twelve patients with acquired immune deficiency syndrome (AIDS)-related Kaposi's sarcoma (KS) were followed prospectively. Univariate and multivariate analyses were performed to determine significant predictors of survival and development of opportunistic infection (OI) from the time of diagnosis of KS. Clinical variables analyzed were age at onset, presence of systemic symptoms, prior or coexistent OI, development of OI greater than 3 months following KS diagnosis, and extent of disease. Laboratory variables analyzed were absolute number of peripheral T-helper lymphocytes (T4), helper/suppressor ratio (T4/T8), serum beta-2-microglobulin, and serum acid labile alfa interferon. Three independent variables were predictive of shorter survival: (1) prior or coexistent OI (P = .02), (2) presence of systemic symptoms (P = .001), and (3) absolute T4 count less than 300 cells/microL (P = .002). Based on survival, patients with AIDS-related KS can be divided into four groups: (1) those with no prior or coexistent OI, no systemic symptoms, T4 greater than or equal to 300 cells/microL (median survival, 31 months): (2) those with no prior or coexistent OI, no systemic symptoms, and T4 less than 300 cells/microL (median survival, 20 months); (3) those with no prior or coexistent OI and presence of systemic symptoms (median survival, 15 months); and (4) those with prior or coexistent OI (median survival, 7 months).

Sperm and seminal plasma antibodies in acquired immune deficiency (AIDS) and other associated syndromes

Although HIV has been established as the etiologic agent in AIDS, other contributory cofactors may be responsible for selective clinical manifestations of the syndrome. While the pathogenesis remains unclear, the development of immunologic abnormalities observed in some homosexual males with AIDS and AIDS-related complex may be attributed to repeated exposure to allogeneic sperm and seminal plasma components. Accordingly, antibody levels to semen fractions were measured in sera from 338 individuals (295 AIDS, 36 ARC, 16 randomly selected homosexuals, 29 patients with infectious hepatitis, 12 hemophiliacs, 20 rheumatic disease patients, and 24 healthy heterosexual adults). The methods were (i) passive hemagglutination for antibodies to human seminal plasma (HuSePl), and (ii) indirect immunofluorescence (IF) assay on methanol-fixed human sperm noting staining of acrosomal, equatorial, postnuclear, and tail main-piece regions. HuSePl was positive in 31% AIDS sera, while 39% were positive by IF. ARC sera were 30% positive for HuSePl and 38% positive IF. No control sera were positive. Results reveal a significant incidence of antibody to sperm and seminal plasma components in ARC and AIDS patients. Because of the known immunomodulating properties of both, it is possible that these responses may indicate risk factors for disease progression and severity.

Identification of human immunodeficiency virus sequences by using in vitro enzymatic amplification and oligomer cleavage detection

Human immunodeficiency virus (HIV) has been associated with acquired immunodeficiency syndrome and related disorders. Assays to detect antibodies to HIV proteins have been developed and used to screen sera for the identification of individuals who have been exposed to the virus. Although these serological tests have significant sensitivity and specificity for detecting exposure to the virus, they do not provide direct identification of HIV. We report here the application of recently developed nucleic acid amplification and oligonucleotide-based detection procedures for the identification of HIV sequences in established infected cell lines and in cells cultured from infected individuals.

Presence of chromosomal abnormalities and lack of AIDS retrovirus DNA sequences in AIDS-associated Kaposi's sarcoma

The frequent occurrence of Kaposi's sarcoma (KS) in association with the acquired immune deficiency syndrome (AIDS) could be due to the fact that the etiological agent of this tumor is the same retrovirus causing AIDS, to another oncogenic virus frequently found in AIDS patients, or to the unmasking of the tumorigenic potential of KS cells by immunosuppression. We have therefore investigated the presence of DNA sequences homologous to the AIDS retrovirus, cytomegalovirus (CMV), and hepatitis B virus in 13 KS necropsies and biopsies from AIDS patients. All KS DNA samples were negative for AIDS retrovirus or hepatitis B DNA sequences. Two DNAs from necropsies contained CMV DNA, but the data suggested the presence of replicating CMV DNA due to generalized infection. We have also studied cell cultures derived from KS skin biopsies of AIDS patients. These cultures had a short lifetime in vitro and expressed some markers of endothelial cells. The cells were not tumorigenic in nude mice but contained a number of chromosomal rearrangements which were often monoclonal within the same culture. However, these abnormalities were different from culture to culture and even in cultures from the same biopsy. The presence of these chromosomal abnormalities seemed to correlate with the cell positivity for endothelial markers. Taken together these results indicate that neither the AIDS retrovirus, CMV, or hepatitis B virus is directly responsible for the altered growth of KS cells, that KS may be polyclonal even within the same lesion, and that KS cells have a tendency to karyotypic rearrangements.

Partial plasma exchange in patients with AIDS and Kaposi's sarcoma. Plasmapheresis in AIDS

Intensive plasma exchange was performed in seven male homosexual patients with AIDS and Kaposi's sarcoma. Serial 1.2 plasma volume exchange procedures were performed three times a week for six weeks. In five of the patients, plasma replacement included gamma globulin in the form of plasma (two patients), or an IV IgG preparation (three patients). No changes in the mean number of helper-inducer or suppressor-cytotoxic cells were noted during the treatment period or the weeks following completion of the last procedure. The mean mitogenic response of the patients' lymphocytes to PHA increased by 32.4% during the course of the plasmapheresis procedures (p less than .05), but returned to baseline over the eight weeks following treatment. Mitogenic responsiveness to PWM did not significantly increase during the course of treatment. No regression of Kaposi's sarcoma lesions was found in any of the patients treated.

Thymosin alpha 1 and thymosin beta 4 in serum: comparison of normal, cord, homosexual and AIDS serum

Thymosin alpha 1 and thymosin beta 4 were first isolated from thymosin fr. 5 and have demonstrated biological activities on the immune system. They are chemically distinct and differ in their immunological activity profiles. The levels of thymosin alpha 1 and thymosin beta 4 were assessed by radioimmunoassay in the same serum samples. Normal thymosin alpha 1 levels were 670 +/- 163 pg/ml for males and 652 +/- 162 pg/ml for females. Normal thymosin beta 4 levels were 974 +/- 400 ng/ml for males and 889 +/- 345 ng/ml for females. No correlation between the levels of the peptides in serum from normal donors was observed. Although many samples of serum from neonates (cord blood), homosexuals and AIDS patients had elevated levels of one or both peptides, no correlation between the two peptides was found. Of potential significance is the observation that while thymosin alpha 1 and beta 4 are elevated in many individuals with AIDS (57 and 48% respectively), the individuals with AIDS related immune dysfunctions had predominantly elevated thymosin alpha 1 (54 vs 15%). These studies suggest that serum levels of the two peptides are modulated separately and that both are of potential value in defining the risk of individuals for developing AIDS.

Treatment of epidemic Kaposi's sarcoma with etoposide or a combination of doxorubicin, bleomycin, and vinblastine

An epidemic of disseminated Kaposi's sarcoma in male homosexuals has recently been described. Forty-one evaluable patients with epidemic Kaposi's sarcoma were treated with etoposide. The majority of these patients had early stage disease, no prior opportunistic infections, and no prior therapy. Twelve patients (30%) achieved complete remission, 19 (46%) partial remission, and ten (24%) no response. With follow-up time to 31 months, the median response duration is nine months. The median survival of patients with complete and partial remissions has not been reached. A combination of doxorubicin (Adriamycin, Adria Laboratories, Columbus, Ohio), bleomycin, and vinblastine (ABV) was used in 31 evaluable patients with epidemic Kaposi's sarcoma. The majority of these patients had late stage disease, prior opportunistic infections, or had failed prior treatment. Seven patients (23%) achieved complete remission, 19 (61%) partial remission, and five (61%) no response. With follow-up time to 24 months, the median response duration is eight months. The projected median survival for all patients treated with ABV is nine months. Both regimens were well tolerated, with an overall response rate of 76% for etoposide and 84% for ABV. However, while successfully treating the Kaposi's sarcoma, the underlying immune deficiency in these patients has persisted. Future treatments of Kaposi's sarcoma will need to focus on reversing the underlying immune incompetence as well as controlling the malignant manifestations of Kaposi's sarcoma arising in relation to the acquired immune deficiency syndrome.

Immunologic abnormalities in homosexual men. Relationship to Kaposi's sarcoma

Studies were performed to define the immunologic status of various groups of homosexual men including homosexual men with Kaposi's sarcoma, healthy homosexual men who were of similar ages to the homosexual patients with Kaposi's sarcoma and homosexual men with hyperplastic lymphadenopathy. Heterosexual men with Kaposi's sarcoma were also studied. Immunologic parameters which were examined included serum immunoglobulin levels, enumeration of B cells, T cells, and T-cell subsets, and quantitation of lymphocyte responsive to phytohemagglutinin (PHA) and pokeweed mitogen (PWM). Significant immunologic abnormalities were observed in all three groups of homosexuals studied. These were most severe in the homosexuals with Kaposi's sarcoma, somewhat less severe in homosexual men with lymphadenopathy, and least marked but still significant in healthy homosexual men. Heterosexual men with Kaposi's sarcoma displayed essentially normal immunologic profiles. The possible etiologic factors underlying the immunologic abnormalities in the male homosexual population studied and the role of an altered immune system in the development of and the fulminant course of Kaposi's sarcoma in these patients are discussed.