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B Safai

Publications and source records attributed to B Safai.

At least 37 records · Page 2Linked to original sources
PubMed1987

A conserved region at the COOH terminus of human immunodeficiency virus gp120 envelope protein contains an immunodominant epitope.

A highly immunogenic epitope from a conserved COOH-terminal region of the human immunodeficiency virus (HIV) gp120 envelope protein has been identified with antisera from HIV-seropositive subjects and a synthetic peptide (SP-22) containing 15 amino acids from this region (Ala-Pro-Thr-Lys-Ala-Lys-Arg-Arg-Val-Val-Gln-Arg-Glu-Lys-Arg). Peptide SP-22 absorbed up to 100% of anti-gp120 antibody reactivity from select HIV+ patient sera in immunoblot assays and up to 79% of serum anti-gp120 antibody reactivity in competition RIA. In RIA, 45% of HIV-seropositive subjects had antibodies that bound to peptide SP-22. Human anti-SP-22 antibodies that bound to and were eluted from an SP-22 affinity column reacted with gp120 in RIA and immunoblot assays but did not neutralize HIV or inhibit HIV-induced syncytium formation in vitro, even though these antibodies comprised 70% of all anti-gp120 antibodies in the test serum. In contrast, the remaining 30% of SP-22 nonreactive anti-gp120 antibodies did not react with gp120 in immunoblot assays but did not react in RIA and neutralized HIV in vitro. Thus, approximately 50% of HIV-seropositive patients make high titers of nonneutralizing antibodies to an immunodominant antigen on gp120 defined by SP-22. Moreover, the COOH terminus of gp120 contains the major antigen or antigens identified by human anti-gp120 antibodies in immunoblot assays.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Epidermal Langerhans cells--a target for HTLV-III/LAV infection.

Langerhans cells (LC) are bone marrow-derived, Ia+, CD1+, CD4+, ATPase+ dendritic antigen-presenting cells within the human epidermis. Since the CD4 molecule has been implicated as a receptor structure for HTLV-III/LAV (human T-cell leukemia virus/lymphadenopathy-associated virus), we asked whether LC from HTLV-III/LAV-seropositive individuals display signs of HTLV-III/LAV infection. In skin biopsies from 7/40 HTLV-III/LAV-infected persons (1 asymptomatic carrier, 2 patients with acquired immunodeficiency syndrome (AIDS)-related complex and 4 patients with AIDS), LC were the only epidermal cells to react with a monoclonal antibody specific for the HTLV-III core protein p17. A varying percentage of p17+ LC were morphologically altered with blunt dendrites and poorly demarcated cellular contours. In one of these biopsies, the presence of LC-associated viral particles characteristic of HTLV-III/LAV as well as cytopathic changes in approximately one-third of the LC population were demonstrated by electron microscopy. These results strongly suggest that LC may harbor HTLV-III/LAV. The infection of LC with this retrovirus may have deleterious consequences for the immunologic functions of this cell system and may thus contribute to both the acquisition of immunodeficiency and the infectious and neoplastic complications of AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Pathophysiology and epidemiology of epidemic Kaposi's sarcoma.

The epidemic form of Kaposi's sarcoma (KS) that occurs in patients with the acquired immune deficiency syndrome (AIDS) produces lesions that, histopathologically, are indistinguishable from those of classical KS or of the endemic form of the disease seen in children and adults in certain areas of Africa. There are, however, important differences in the pathogenesis of the disease in the different groups affected by the neoplasm. Compared with classical KS in people of eastern European and Mediterranean descent, which commonly takes a protracted, indolent course, the epidemic Kaposi's sarcoma (EKS) is far more aggressive. However, the KS seen in adults in endemic areas of Africa may also become florid and rapidly progressive after years of quiescence. Some degree of immune dysfunction is thought to be a factor in all forms of KS, with immune depression being the hallmark of EKS and the setting in which it occurs. Cytomegalovirus (CMV) is thought to be at least a cofactor in the disease, but it has also been suggested that the etiologic agent of AIDS, human immunodeficiency virus (HIV), may also play a role in EKS.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Antigen-specific and polyclonal B-cell responses in patients with acquired immunodeficiency disease syndrome.

Patients with acquired immunodeficiency disease syndrome (AIDS) show a complex spectrum of immunological abnormalities. We have examined B-lymphocyte function in 58 patients with AIDS and Kaposi's sarcoma. The major finding has been that the specific antibody response to sheep red blood cell antigen in vitro is severely depressed. Analysis of the defect in specific antibody production indicates that it is not caused by lack of T-cell help or excessive T-cell suppression, and suggests that it reflects an abnormality of the B-cell compartment itself. The defect does not affect the ability of B cells to respond to polyclonal stimulation. The possibility is considered that continuous hyperactivation of B cells in AIDS patients (as reflected in the increase in both immunoglobulin-secreting cells and serum immunoglobulin levels) results in depletion of the pool from which precursors for antigen specific B-cell responses are normally recruited.

Acquired Immunodeficiency Syndrome↗
PubMed1986

Identification with the monoclonal antibody 26.163 of a determinant shared by the beta chains of the gene products of the HLA-DR, DQ, and DP loci.

Immunochemical studies (sequential immunoprecipitation followed by SDS-PAGE and two-dimensional gel electrophoresis) have shown that the monoclonal antibody (MoAb) 26.163 reacts with HLA-DR, DQ, and DP antigens. Testing with isolated alpha and beta chains of HLA class II antigens and immunoblot analysis also demonstrated that the determinant defined by the MoAb 26.163 is localized on beta chains and does not require their association with alpha chains for its expression. The MoAb 26.163 appears to be the first example of a monoclonal antibody with specificity for the gene products of HLA-DR, DQ, and DP loci.

Antibodies, Monoclonal↗
PubMed1986

Importance of complete cutaneous examination for the detection of malignant melanoma.

With the rate of melanoma increasing 1,000% in the past 50 years, the early detection of the disease is becoming more important. Data from 2,239 persons seen at the Manhattan Melanoma/Skin Cancer Detection Screening Program were analyzed to determine if a complete cutaneous examination would significantly increase the chance of detecting melanoma. Thirteen of the fourteen melanomas detected were on anatomic sites normally covered by clothing. Patients having complete skin examinations were 6.4 times more likely to have a melanoma detected than those having partial examinations (p = 0.025). These findings reinforce the importance of complete skin examination for the early detection of malignant melanoma.

Basal Cell Carcinoma↗
PubMed1985

Characterization of envelope and core structural gene products of HTLV-III with sera from AIDS patients.

The envelope (env) and structural (gag) gene products of human T-cell leukemia (lymphotropic) virus type III were identified by immunoaffinity chromatography, immunoprecipitation, and two-dimensional oligopeptide mapping methods. The env gene specifies a glycosylated polypeptide with a molecular weight of 160,000 (gp160) that is processed to gp120 and smaller gene products. The gag gene specifies two polypeptides of 70,000 and 55,000 molecular weight (p70 and p55), both of which contain p24, the major structural protein of the mature virion. The techniques in this study can be used to define the extent of variability of the env gene product among different virus isolates and may identify the nature and patterns of the humoral immune response that lead to an immunologically protected state.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Analysis of T cell subsets in different clinical subgroups of patients with the acquired immune deficiency syndrome. Comparison with the "classic" form of Kaposi's sarcoma.

Ninety patients were grouped according to three different forms of acquired immune deficiency syndrome (AIDS): Kaposi's sarcoma "recent outbreak" type (38), reactive lymphadenopathy (27), and opportunistic infections (17), and a fourth group of patients with "classic" Kaposi's sarcoma (8). All patients with "classic" Kaposi's sarcoma were previously treated with electron-beam irradiation. These four groups were compared with 40 normal control subjects. Peripheral blood mononuclear cells isolated by density separation were reacted with a panel of mouse monoclonal antibodies that recognizes all peripheral blood T cells (OKT3-positive), helper (OKT4-positive), and suppressor (OKT8-positive) T cell subsets. The OKT4/OKT8 ratio was used to define the balance between these two subsets. All three groups with AIDS with or without Kaposi's sarcoma showed a decrease in the OKT4/OKT8 ratio. The group with "classic" Kaposi's sarcoma showed individual T cell subset values that were also abnormal. These findings confirm the previously reported imbalance of T cell subsets in patients with AIDS and Kaposi's sarcoma, which is also evident in patients with treated "classic" Kaposi's sarcoma.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Human leukocyte antigen associations in basal cell carcinoma.

Basal cell carcinoma is the most common form of skin cancer and is one in which both host and environmental factors are thought to play a role in its pathogenesis. For an investigation of the role of human leukocyte antigen (HLA)-associated variations in genetic susceptibility, thirty-one patients with multiple basal cell carcinomas were typed for HLA-A, B, C, and DR antigens. Patients were compared with both local and appropriate ethnic group controls. No statistically significant association with HLA-A, B, or C antigens was noted in any group. However, a significant increase in HLA-DR1 was noted in non-Irish, non-Ashkenazi patients. A tendency toward a decrease in HLA-DR3 was also noted among patients of Irish or Ashkenazi Jewish descent. The role of HLA-associated genetic factors in this form of skin cancer needs further investigation.

Basal Cell Carcinoma↗
PubMed1985

Basal cell carcinoma and breast carcinoma following repeated fluoroscopic examinations of the chest.

A 69-year-old white Italian woman was first seen at Memorial Sloan-Kettering Cancer Center in 1981 concerning several skin growths on her back. The patient had had several basal cell carcinomas surgically removed from her back during the preceding 5 years. There was no history of arsenic ingestion or prolonged sun exposure and her family history was negative for skin cancer. The patient had developed pulmonary tuberculosis in 1938 and was treated with pneumothorax therapy. She had had more than 50 fluoroscopic examinations of the chest following this therapy, as well as multiple diagnostic x-ray films since that time. She recalled that she had faced the fluoroscopy beam during the procedure. In 1959, she had a transabdominal hysterectomy for fibroid tumors. In 1980 she underwent a right modified radical mastectomy for adenoid cystic carcinoma of the breast; biopsies of lymph nodes were negative. Physical examination revealed a thin, white woman with a right mastectomy scar. On the back, clustered in the interscapular region, were multiple scars and nine erythematous nodules with pearly borders, telangiectasia, and translucent surfaces. Within several nodules there were areas of light and dark brown pigmentation. There were no other suspicious lesions on the head, chest, or extremities, nor did the patient show any evidence of the basal cell nevus syndrome. Biopsy of all lesions revealed basal cell carcinoma, some of which were pigmented, without evidence of chronic radiodermatitis. All lesions were treated with curettage and electrodesiccation three times with good cosmetic results (Fig. 1).

Breast Neoplasms↗
PubMed1985

The natural history of Kaposi's sarcoma in the acquired immunodeficiency syndrome.

Kaposi's sarcoma is a multifocal systemic neoplasm histologically characterized by proliferating fibroblastic and microvascular elements. Initial signs include macules, papules, or nodules on the skin or mucosal surface. Lesions are frequently found on the trunk, arms, and head and neck. In general, sites of involvement and tumor load do not correlate with prognosis. A general decrease in the functional capacities of T and B cells is found in most patients. Kaposi's sarcoma is reported as the initial manifestation of the acquired immunodeficiency syndrome (AIDS) in approximately 30% of cases. Most cases are in men, although it has been reported in all risk groups. Kaposi's sarcoma in AIDS is more frequent among whites and homosexuals than blacks and intravenous drug abusers. Overall mortality is approximately 41%, with over 60% of patients alive at 1 year and 50% at 22 months. Overall survival is 18 months; however, some patients who have had the disease for 3 to 4 years are still doing well.

Acquired Immunodeficiency Syndrome↗
PubMed1985

Spectrum of Kaposi's sarcoma in the epidemic of AIDS.

Kaposi's sarcoma (KS) is seen with increased frequency in the course of the epidemic of acquired immune deficiency syndrome. In this population, KS has manifested in an aggressive and more disseminated fashion as compared to the classical type. As the epidemic of acquired immune deficiency syndrome continues to spread and more cases of KS are evaluated, a distinct diversity in the clinical presentation and in the course of the disease as well as in variation in the prognosis and response to therapy is being observed. A preliminary description of the spectrum of KS in the epidemic of acquired immune deficiency syndrome is presented here.

Acquired Immunodeficiency Syndrome↗