Combination chemotherapy of disseminated Kaposi's sarcoma in patients with the acquired immune deficiency syndrome.

Two clinical trials were conducted to assess the efficacy and safety of a combination chemotherapy regimen for the treatment of Kaposi's sarcoma in patients with the acquired immune deficiency syndrome (AIDS). Eighteen consecutive patients with disseminated Kaposi's sarcoma were treated with a six-drug regimen of doxorubicin (Adriamycin), vinblastine, bleomycin/actinomycin D, vincristine, dacarbazine (ABV/ADV). A brief partial or complete response was achieved in 13 patients. Most patients died of opportunistic infections. Eighteen consecutive patients with disseminated Kaposi's sarcoma were then randomly assigned to therapy with either recombinant alpha interferon or ABV/ADV. The treatment responses in these two groups were comparable to results of earlier trials, and the incidence of opportunistic infections during therapy did not differ between the two treatment arms. It is concluded that chemotherapy is effective and safe for use in palliative management of Kaposi's sarcoma in patients with AIDS.

The relationship of serum alpha-interferon and ultrastructural markers in HIV-seropositive individuals.

Two inclusions of the endoplasmic reticulum, tubuloreticular inclusion (TRI) and cylindrical confronting cisternae (CCC), are common to lymphocytes from individuals with AIDS and AIDS-related conditions. Both inclusions can be induced in vitro with alpha-interferon (IFN). IFN may also be elevated in both populations. Circulating lymphocytes containing TRI are seen prior to the appearance of serum IFN. CCC appear in circulating lymphocytes after TRI, and both regularly antedate the diagnosis of AIDS. As in systemic lupus erythematosus (SLE), it can be hypothesized that lymphocytes exposed locally to IFN acquire TRI and then appear in the peripheral blood to be followed subsequently by IFN. The data strongly suggest that the appearance of these markers may predict the progression to AIDS.

Serum interferon in patients with psychosis.

High titers of interferon were found in serum from 20 (24.4%) of 82 patients with psychosis and from only two (3.1%) of 64 control subjects. Interferon-positive patients were more likely than interferon-negative patients to have had a recent onset or exacerbation of their illness and to be on low-dose or no medication. No interferon was detected in the CSF of 65 patients or 20 control subjects. These findings suggest that there may be immunological abnormalities or viral infections in some patients with psychosis.

Interferon-induced 2'-5' oligoadenylate synthetase during interferon-alpha therapy in homosexual men with Kaposi's sarcoma: marked deficiency in biochemical response to interferon in patients with acquired immunodeficiency syndrome.

Titers of circulating interferon (IFN) and the activity of 2'-5' oligoadenylate (2-5A) synthetase, an enzyme specifically induced by IFN, were measured in 28 homosexual men with acquired immunodeficiency syndrome (AIDS) who received one- to six-month courses of antineoplastic therapy with IFN-alpha and in homosexual and heterosexual controls. Fifteen of the patients and two of seven healthy homosexual men had high endogenous levels of 2-5A synthetase. IFN therapy induced further increases in this enzyme in only 10 of the 28 patients with AIDS. Furthermore, peripheral blood cells from all but one of the patients with AIDS and homosexual controls tested were markedly deficient in their ability to respond to IFN in vitro, as measured by increased levels of 2-5A synthetase. We did not find a statistical correlation between cytomegalovirus viremia and pretherapy endogenous circulating IFN, nor any apparent correlation between disseminated infection with cytomegalovirus and either basal levels of 2-5A synthetase or changes in enzyme level during therapy. Pretherapy circulating IFN was significantly correlated with progressive Kaposi's sarcoma during therapy, but rises in levels of 2-5A synthetase were not sufficient to predict a good clinical response.

Human lymphoblastoid interferon treatment of Kaposi's sarcoma in the acquired immune deficiency syndrome. Clinical response and prognostic parameters.

Thirty consecutive patients with the acquired immune deficiency syndrome were treated with intramuscular human lymphoblastoid interferon for Kaposi's sarcoma. Patients were divided into three groups receiving 7.5 million units/m2 per day, 15 million units/m2 per day, or 25 million units/m2 per day for 28 days. Because of dose-limiting toxicity in the highest dose group, all patients received between 6 and 15 million units/m2 per day. There were three partial responses and four minor responses. The responses were not dependent on drug dose, but did correlate with higher total lymphocyte and OKT4-positive lymphocyte numbers and absence of prior opportunistic infection. Patients who had endogenous acid-labile alpha-interferon prior to therapy were more likely to have progressive disease during interferon administration.

Serum alpha interferon and lymphocyte inclusions in systemic lupus erythematosus.

The relationship between serum acid-labile alpha interferon and tubuloreticular inclusions within the cytoplasm of circulating lymphocytes was studied in 46 patients with systemic lupus erythematosus. Elevated levels of interferon (greater than or equal to 8 IU/ml) were found in 17 patients and lymphocyte inclusions in 35. The mean serum interferon concentration in patients with lymphocyte inclusions was significantly higher than in patients without inclusions (17.2 versus 2.4 IU/ml, p less than 0.01). Inclusions were found in 16 of 17 patients with elevated interferon and also in 19 of 29 patients without interferon (p = 0.026). In lupus, serum interferon appears to be a sufficient though not an essential marker for the presence of lymphocyte inclusions.

Persisting illness and fatigue in adults with evidence of Epstein-Barr virus infection.

Clinical, serologic, virologic, and immunologic evaluations for 31 adults with chronic illness and fatigue suggested that 23 had persisting Epstein-Barr virus infection. Among these 23 patients, cellular immune mechanisms were generally normal, but 4 had mild immunoglobulin deficiencies. However, 20 patients had abnormal serologic profiles specific for Epstein-Barr virus shown by significantly elevated titers of antibodies to the viral capsid antigen or early antigen, or by a deficiency of late-appearing antibodies. In 11 of 15 patients tested, circulating immune complexes were found. Circulating interferon was not found in 18 patients tested, but the activity of 2-5 oligoadenylate synthetase, an interferon-induced enzyme, was increased in 5 patients studied. Of 19 patients, 18 had persisting suppressor T-cell activity typically found in patients recovering from acute infectious mononucleosis. We believe that the Epstein-Barr virus may be associated with chronic illness in adults.

A sensitive immunoenzymometric assay for 2',5'-oligoadenylate. Detection of elevated 2',5'-oligoadenylate synthetase in human peripheral mononuclear cells.

A competition immunoenzymometric assay for 2',5'-oligoadenylate was developed and employed to measure the interferon-inducible enzyme 2',5'-oligoadenylate synthetase in cell extracts. Microtiter plates coated with a novel conjugate of p5'A2'p5'A2'p5'A and N-(2-aminoethyl)-carbamylmethylated-Ficoll (AECM-Ficoll) bound rabbit polyclonal or mouse monoclonal antibody directed against 2',5'-oligoadenylate. Binding was inhibited by soluble 2',5'-oligoadenylate. Estimates of 2',5'-oligoadenylate concentrations based on inhibition of antibody binding compared favorably with those obtained using a protein synthesis inhibition assay. Low concentrations of 2',5'-oligoadenylate synthesized in vitro by extracts of human peripheral mononuclear cells were conveniently estimated using less than or equal to 10(6) cells. Virtually identical results were obtained when either total extract or synthetase bound to poly(I) . poly(C)-agarose was used for the in vitro incubation. When peripheral mononuclear cells were incubated in vitro with interferon, the normally low levels of 2',5'-oligo(A) synthetase rose dramatically. The assay was employed to measure synthetase levels in peripheral mononuclear cells isolated from patients with systemic lupus erythematosus. Some of these patients were found to have elevated levels of 2',5'-oligoadenylate synthetase.

Acid-labile alpha interferon. A possible preclinical marker for the acquired immunodeficiency syndrome in hemophilia.

Many homosexual men with the acquired immunodeficiency syndrome (AIDS) have an unusual acid-labile form of human leukocyte, or alpha, interferon in their serum. Male patients with classic hemophilia treated with lyophilized clotting-factor concentrates are also at high risk for the development of AIDS. To determine whether the level of alpha interferon may be a preclinical marker of early subclinical disease, we examined stored plasma and serum from three hemophilic patients with AIDS. Persistently elevated levels of the acid-labile form of alpha interferon were found in all three patients. In two patients the appearance of circulating alpha interferon preceded the onset of clinical disease by 3 to 10 months. In contrast, alpha-interferon levels were not elevated in 43 of 46 unselected patients with hemophilia; three of these patients had transient elevations. These results suggest that acid-labile alpha interferon may be a marker that can be used to identify affected asymptomatic members of high-risk groups before the onset of clinical disease.

Interferon-induced alterations in cells: relevance to viral and nonviral diseases.

Thus, interferon has diverse effects on cellular structure and/or function. Although some of these effects may be involved in interferon's antiviral actions, they may also play a role in normal physiologic processes. Inappropriate production of or response to interferon may, therefore, contribute to abnormal cell-cell interactions seen in a variety of disease states. In view of the increasingly widespread use of human interferons in antiviral and anticancer therapy, further investigation is needed to understand the many effects of interferons on cells. For example, insight into the biologic properties of each of the numerous subspecies of alpha-interferon may allow more rational decisions about the type of interferon, dose, and administration schedule necessary for maximal beneficial effects in cancer patients. Further studies on the immunoregulatory effects of the different types of interferons are also necessary to elucidate whether interferon is involved in the pathophysiology of immune disorders.

Interferon-induced 2'-5' adenylate synthetase in vivo and interferon production in vitro by lymphocytes from systemic lupus erythematosus patients with and without circulating interferon.

The interferon (IFN)-induced enzyme 2-5A synthetase was elevated in mononuclear cells from both serum IFN-positive and -negative systemic lupus erythematosus (SLE) patients. This suggests that a much higher percentage of patients than previously thought produce endogenous IFN. These results may partly explain findings that mononuclear cells from SLE patients are deficient in IFN production in vitro in response to certain IFN inducers. Although normal lymphocytes can produce an acid-labile alpha IFN after stimulation with C. parvum in vitro, the reason for endogenous production of this unusual alpha IFN by SLE patients remains unknown.

Hydrocephalus in weanling mice induced by a temperature-sensitive mutant of vesicular stomatitis virus.

Hydrocephalus developed in weanling Swiss-Webster mice after intracerebral (IC) inoculation of a naturally selected temperature-sensitive (ts) mutant of vesicular stomatitis virus (VSV). This spontaneous ts mutant was isolated from a persistent infection (pi) of mouse L cells with VSV, and named VSV-tspi 364 (complementation Group I). High doses of the mutant virus induced hydrocephalus in 87% of the mice. Infected mice were clinically asymptomatic, except for a few with transient hind-limb paralysis and proximal muscle weakness. After inoculation, mice were killed every other day for the first two weeks, and weekly thereafter for two months. Virological studies showed replication in the brain in the first nine days post-inoculation (DPI). Neutralizing antibody titers increased rapidly after 15 DPI, and elevated titers were measured at 30 DPI. Pathologically, there was patchy ependymal cell necrosis in the aqueduct and lateral ventricles, as early as the second DPI. Mild meningoencephalitis and severe ependymal cell necrosis with focal aqueductal stenosis were present iun the first two weeks of infection. Hydrocephalus began as early as 10 DPI and became severe at 28 DPI. This represents the first animal model for hydrocephalus following IC inoculation of a spontaneous ts mutant of a rhabdovirus. In our study, inoculation of mice with wild-type VSV and with other spontaneous and chemical ts mutants of VSV IC as well as with tspi 364 by other routes did not cause hydrocephalus.

Acid-labile human leukocyte interferon in homosexual men with Kaposi's sarcoma and lymphadenopathy.

Some immunologic parameters in homosexual patients with Kaposi's sarcoma (KS) or unexplained lymphadenopathy resemble findings in patients with autoimmune diseases such as systemic lupus erythematosus (SLE). Many patients with SLE have an unusual acid-labile form of human leukocyte interferon (HuIFN-alpha) in their serum. Sera from 91 homosexual men were tested for the presence of HuIFN. Of 27 patients with KS, 17 had significant titers of HuIFN in their serum. Ten of 35 patients with lymphadenopathy and three of four patients with other clinical symptoms also had circulating HuIFN. In contrast, only two of 25 apparently healthy subjects had serum HuIFN. All 32 samples of HuIFN had antiviral activity on bovine cells, a characteristic of HuIFN-alpha, and all of 14 representative samples tested were neutralized by antibody to HuIFN-alpha. In addition, the HuIFN-alpha in six of eight representative patients was inactivated at pH 2 and therefore appears to be similar to the HuIFN-alpha found in patients with SLE. These findings suggest that an autoimmune disorder may underly lymphadenopathy and KS in homosexual men.

Systemic lupus erythematosus: presence in human serum of an unusual acid-labile leukocyte interferon.

A previously undescribed species of human leukocyte, or alpha, interferon is present in the serum of many patients with systemic lupus erythematosus. It was shown to be alpha-interferon by neutralization with specific antiserums, affinity column chromatography, and antiviral activity on bovine cells. However, 23 of 30 interferon samples tested were inactivated by incubation at pH 2, a characteristic of human "immune," or gamma, interferon. Multiple samples of interferon from the same patient had similar biological properties, but samples from different patients were not all identical, suggesting that several variants of this species of human alpha-interferon may exist.

Neurovirulence mutant of vesicular stomatitis virus with an altered target cell tropism in vivo.

Intracerebral infection of weanling Swiss mice with a temperature-sensitive (ts) mutant of vesicular stomatitis virus (VSV), ts pi364, resulted in a unique neuropathological syndrome not previously described with other VSV mutants. Mice infected with wild-type VSV died from an acute encephalitis characterized by neuronal necrosis and efficient virus replication in both brain and spinal cord. In contrast, with VSV ts pi364, the most prominent histopathological feature was destruction of the ependyma of the lateral ventricles. Virus antigen was also limited to the leptomeninges and the lateral ventricles. Infected mice survived and developed hydrocephalus. Replication of ts pi364 in the brain was 10- to 100- fold less than that of wild-type VSV, and appearance of virus in the spinal cord was delayed. VSV ts pi364 was isolated from mouse cells persistently infected with VSV. Another VSV ts pi mutant, isolated from the same persistent infection, behaved in vivo like wild-type VSV, even though both mutants were very similar in plaque size, reversion frequency, cut-off temperature, and synthesis of virus-specific proteins at semipermissive temperature. These results strongly suggest that VSV ts pi364 has a second, non-ts mutation which results in a restricted target cell range in vivo; wild-type VSV can infect both neurons and ependymal cells, whereas ts pi364 does not replicate in neurons.

Persistent infection of L cells with vesicular stomatitis virus: evolution of virus populations.

A previous report (Youngner et al., J. Virol. 19:90-101, 1976) documented that noncytocidal persistent infection can be established with wild-type vesicular stomatitis virus (VSV) in mouse L cells at 37 degrees C and that a rapid selection of RNA(-), group I temperature-sensitive (ts) mutants consistently occurs in this system. To assess the selective advantage of the RNA(-)ts phenotype, evolution of the virus population was studied in persistent infections initiated in L cells by use of VSV ts 0 23 and ts 0 45, RNA(+) mutants belonging to complementation groups III and V. In L cells persistently infected with ts 0 23, the ts RNA(+) virus population was replaced gradually by viruses which had a ts RNA(-) phenotype. VSV ts 0 45 (V) has another marker in addition to reduced virus yield at 39.5 degrees C: a defective protein (G) which renders virion infectivity heat labile at 50 degrees C. Persistent infections initiated with this virus (ts, heat labile, RNA(+)) evolved into a virus population which was ts, heat resistant, and RNA(-). These findings suggest that the ts phenotype itself is not sufficient to stabilize the VSV population in persistently infected L cells and also indicate that the ts RNA(-) phenotype may have a unique selective advantage in this system. In addition to the selection of ts RNA(-) mutants, other mechanisms which also might operate in the maintenance of persistent VSV infections of L cells were explored. Whereas defective-interfering particles did not seem to mediate the carrier state, evidence was obtained that interferon may play a role in the regulation of persistent infections of L cells with VSV.