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H E Prince

Publications and source records attributed to H E Prince.

At least 55 records · Page 3Linked to original sources

In vitro activation of T lymphocytes from human immunodeficiency virus (HIV)-seropositive blood donors. I. Soluble interleukin 2 receptor (IL2R) production parallels cellular IL2R expression and DNA synthesis.

We investigated the relationship of soluble interleukin 2 receptor (sIL2R) production to cellular IL2R expression and DNA synthesis by mitogen-stimulated mononuclear cells from blood donors seropositive for human immunodeficiency virus (HIV). SIL2R was measured using an enzyme-linked immunosorbent assay which employed 2 anti-IL2R monoclonal antibodies recognizing distinct IL2R epitopes. Decreased phytohemagglutinin-induced DNA synthesis and cellular IL2R expression were accompanied by decreased levels of sIL2R in cell culture supernatants. Similar findings were observed for pokeweed mitogen-induced responses. There was no detectable spontaneous secretion of sIL2R into culture supernatants by unstimulated mononuclear cells from either HIV-seropositive or control seronegative donors. These findings indicate that the in vitro T-cell activation defects which characterize HIV infection include decreased sIL2R production, as well as decreased cellular IL2R expression and DNA synthesis. Further, they show that assessment of supernatant sIL2R levels can be used as a valid, reliable assay for T-cell activation.

Acquired Immunodeficiency Syndrome↗

In vitro activation of T lymphocytes from HIV-seropositive blood donors. II. Decreased mitogen-induced expression of interleukin 2 receptor by both CD4 and CD8 cell subsets.

Mononuclear cells (MC) from many individuals exposed to human immunodeficiency virus (HIV) exhibit a reduced proliferative response to a suboptimal concentration of phytohemagglutinin (PHA). However, the relative contributions of the 2 major T-cell subsets, namely CD4 and CD8 lymphocytes, to this reduced response remain unclear. Based on reports that interleukin 2 receptor (IL2R) expression correlates well with proliferative responses in HIV infection, we used dual-color cytofluorometry to measure IL2R expression by CD4 and CD8 cells following PHA activation of MC from HIV-seropositive blood donors. For data analysis, this study group was divided into two subgroups on the basis of DNA synthesis responses (seropositive with normal DNA synthesis, designated sero + NML, or seropositive with decreased DNA synthesis, designated sero + LOW). When compared to the seronegative control and sero + NML groups, the sero + LOW group exhibited significant reductions in the percentage of MC expressing IL2R, the proportion of CD4 cells expressing IL2R, and the proportion of CD8 cells expressing IL2R. In contrast, these parameters were unchanged in the sero + NML group compared to the control group. These findings show that reduced PHA-induced proliferative responses by MC from HIV-infected persons are associated with decreased IL2R expression by both CD4 and CD8 lymphocyte subsets.

Antigens, Differentiation, T-Lymphocyte↗

Flow cytometric analysis of lymphocyte activation in the mixed lymphocyte response.

Interleukin 2 receptor (IL2R) expression may be a useful parameter for assessing lymphocyte activation in the mixed lymphocyte response (MLR). However, the contribution of irradiated stimulator (S*) cells to the levels of IL2R+ cells recovered must first be defined. We have used a flow cytometric parameter termed the sip count to assess this potential contribution of S* cells. This parameter, which is the number of cells within a defined cell gate, is a reflection of the viable cell number per culture well, since (a) a constant number of cells were plated per well on day 0, (b) cells recovered from a well were resuspended in a constant volume, (c) the flow cytometer aspirated (sipped) a constant volume of cell suspension, and (d) nonviable cells were not included in the gate. Sip count assessment showed that only 5% of S* cells were recoverable by day 4 of culture; in contrast, 70% or more of unstimulated responder cells were recoverable. Sip counts of MLR cultures identified an increase in cell number beginning on day 5, reflecting DNA synthesis and cell division. We then used the sip count to assess changes in the levels of IL2R+ cells in MLR cultures. The number of IL2R+ cells continued to increase up to day 7, even though maximal DNA synthesis occurred on day 5. Further, dual color analysis revealed that the proportion of CD4 cells expressing IL2R was maximal on day 5, whereas the proportion of CD8 cells expressing IL2R continued to increase until day 9. These findings show that flow cytometry can be used to study lymphocyte activation by alloantigens.

Antigens, Differentiation, T-Lymphocyte↗

Abnormalities of interleukin 2 receptor expression associated with decreased antigen-induced lymphocyte proliferation in patients with AIDS and related disorders.

Several parameters of lymphocyte interleukin 2 receptor (IL-2R) expression in response to tetanus toxoid (TT) were monitored using a receptor-specific monoclonal antibody and flow cytometry in patients with acquired immunodeficiency syndrome (AIDS, n = 6), AIDS-related complex (ARC, n = 8), or lymphadenopathy syndrome (LAS, n = 9). These parameters, measured on days 6 and 7 of culture, included (a) the percentage of recovered lymphocytes expressing IL-2R, (b) the number of IL-2R-positive cells/lymphocyte trigger region (a relative measure of the number of IL-2R-positive cells per culture), and (c) mean fluorescence intensity of IL-2R-positive cells. Data were then assessed in relation to DNA synthesis on day 7 of culture. Normal DNA synthesis was observed in nine patients (Pt-N group), and the mean values for all three IL-2R expression parameters in this group did not significantly differ from those of the healthy control group (n = 20). In contrast, 14 patients exhibited low proliferation (Pt-L group) and mean values for all three parameters were significantly lower in this group compared to both the Pt-N and control groups. When considering individual patient values, day 7 IL-2R+ cell number proved the best predictor of DNA synthesis results: all 14 patients in the Pt-L group exhibited low IL-2R+ cell number, while seven of nine patients in the Pt-N group exhibited normal IL-2R+ cell number. Thus, low TT-induced lymphocyte proliferation in AIDS and related disorders is associated with defective IL-2R expression. Further, assessment of IL-2R+ cell number appears to be a valid alternative assay for monitored antigen-induced T cell proliferation in vitro.

AIDS-Related Complex↗

CD4 and CD8 subsets defined by dual-color cytofluorometry which distinguish symptomatic from asymptomatic blood donors seropositive for human immunodeficiency virus.

As part of a larger study to characterize immune alterations in blood donors seropositive for human immunodeficiency virus (HIV), we measured subsets of CD4 (T helper/inducer) and CD8 (T suppressor/cytotoxic) cells by 2-color cytofluorometry. Alterations observed in asymptomatic seropositive donors (ASP) included: 1) decreased mean levels of Leu 8+ CD4 cells, although the proportion of Leu 8+ cells within the CD4 population was unchanged; 2) a selective increase in Leu 8- CD8 and Leu 18- CD8 cell levels; and 3) increased levels of both CD8 subsets defined by Leu 7, Leu 17, or HLA-DR expression. Alterations observed in symptomatic seropositive donors (SSP) were: 1) a further decrease in Leu 8+ CD4 cell levels, with a decrease in the proportion of Leu 8+ CD4 cells; 2) decreased levels of both Leu 18- and Leu 18+ CD4 subsets; 3) selective increases in Leu 8- and Leu 18- CD8 cell levels; and 4) increases in Leu 7+ CD8, Leu 17+ CD8, and HLA-DR+ CD8 subsets but not the reciprocal negative CD8 subsets. Thus, changes merely reflective of HIV infection included decreased levels of Leu 8+ CD4 cells and increased levels of Leu 8- CD8, Leu 18- CD8, Leu 7+ CD8, Leu 17+ CD8, and HLA-DR+ CD8 cells. Development of symptoms were associated with a further, preferential loss of Leu 8+ CD4 cells, proportional losses of both CD4 subsets defined by Leu 18 expression, and a return to normal levels of Leu 7- CD8, Leu 17- CD8, and HLA-DR- CD8 cells.

Adult↗

Cryopreservation and short-term storage of human lymphocytes for surface marker analysis. Comparison of three methods.

Three methods were compared for the cryopreservation and short-term storage of human lymphocytes for cell surface marker analysis with monoclonal antibodies and flow cytometry. These methods were controlled-rate freezing followed by storage in liquid nitrogen (CR), direct placement into liquid nitrogen (LN), and direct placement at -70 degrees C (-70). Our findings show that the LN and -70 methods of cryopreserving lymphocytes are as effective as the CR method for the purpose of determining T cell and large granular lymphocyte subsets within 1 month after freezing.

Antibodies, Monoclonal↗

Human T cell leukemia virus type III antibody, lymphadenopathy, and acquired immune deficiency syndrome in hemophiliac subjects. Results of a prospective study.

A cohort of 63 hemophiliac subjects was followed for clinical and immunologic abnormalities related to the acquired immune deficiency syndrome (AIDS). When evaluated in early 1984, antibody to human T cell leukemia virus type III (HTLV-III) was detected in the serum of 59 percent (24 of 41) of factor VIII or IX concentrate recipients, but in none (0 of six) of the cryoprecipitate/fresh frozen plasma recipients. HTLV-III-seropositive hemophiliac subjects, on average, had been exposed to twice as much concentrate during the previous year as seronegative hemophiliac subjects. The seropositive group had a significantly lower mean helper/suppressor T cell ratio and absolute helper T cell level than the seronegative group. By early 1984, 13 hemophiliac subjects in the study population had lymphadenopathy and one had AIDS. Antibody to HTLV-III was detected in the serum of 13 of these 14 hemophiliac subjects with overt clinical disease. The prevalence of lymphadenopathy or AIDS among HTLV-III-seropositive hemophiliac subjects was 54 percent (13 of 24). It is concluded that HTLV-III antibody occurs with high frequency in hemophiliac subjects, and is related to the amount of factor VIII or IX concentrate infused. Over half of HTLV-III-seropositive hemophiliac subjects in this population had overt clinical disease with either lymphadenopathy or AIDS.

Acquired Immunodeficiency Syndrome↗

Effect of storage on lymphocyte surface markers in whole blood units.

Pretransplant transfusions of stored donor-specific blood have been shown to improve renal allograft survival while reducing the frequency of lymphocytotoxic antibody production when compared with fresh blood. As part of studies to define the mechanism(s) of this phenomenon, we have monitored lymphocyte surface markers during storage of four units of whole blood. Both mononuclear cell preparations (obtained by density gradient centrifugation) and whole blood preparations were analyzed using monoclonal antibodies and a flow cytometer enabling lymphocytes to be distinguished from other white cells and nonviable cells. In both cell preparations, the percentage of viable lymphocytes expressing CD3 (all T cells), CD4 (T helper cells), CD8 (T suppressor cells,) HLA-class I (A,B,C), or HLA-DR antigens remained stable for at least 14 days, although median fluorescence intensity declined for the first three markers. After day 14, the number of viable lymphocytes recovered from a standard volume of whole blood was insufficient for further assessment of surface markers, even though the white cell count (determined by cell volume) remained near original levels. Thus the distribution of viable lymphocyte subpopulations defined by surface markers was stable for at least two weeks in stored blood; however, a nonspecific loss of lymphocyte viability began after 10 days of storage. These findings suggest that loss of cell viability, rather than loss of specific lymphocyte subpopulations, may be related to the mechanism by which pretransplant transfusion of stored blood improves renal allograft survival without inducing a high incidence of lymphocytotoxic antibody.

Antigens, Differentiation, T-Lymphocyte↗

Anti-HTLV III ELISA and Western blot testing in a blood donor population: implications for donor notification.

We have evaluated the western blot (WB) test for distinguishing anti-HTLV III ELISA-positive donors who have likely been exposed to HTLV III from those that are false positives. Of 1,955 donors, 26 were positive for anti-HTLV III by ELISA testing. Only 6 (23%) were positive by WB: 5 of these 6 were male homosexuals with multiple partners and 5 of 6 had low Th/Ts ratios. The WB-positive donors gave the highest absorbance values in the anti-HTLV III ELISA assay. The immunologic abnormalities in the WB-positive donors suggest that they should be notified of their test results. We conclude that basing a donor notification policy on WB results is the optimum public health strategy for blood banks at the present time.

Antibodies, Viral↗

Cyclosporine inhibits the expression of receptors for interleukin 2 and transferrin on mitogen-activated human T lymphocytes.

The effect of cyclosporine A (CsA) on the mitogen-induced expression of Interleukin 2 receptor (IL2R) and transferrin receptor (TR) was monitored using receptor-specific monoclonal antibodies and flow cytometry. For all mitogens tested (PHA, Con A, OKT3, and Leu 4), expression of IL2R and TR, as well as DNA synthesis (3H-thymidine incorporation), were significantly reduced in the presence of CsA (0.5 microgram/ml). Titration experiments in the OKT3 system, the mitogen system most profoundly affected by CsA, revealed that CsA concentrations as low as 0.05 microgram/ml inhibited IL2R and TR expression and DNA synthesis, and that changes in DNA synthesis reflected changes in IL2R and TR expression. The addition of exogenous IL2 partially abrogated the CsA-mediated inhibition of all three activation parameters (IL2R, TR, DNA synthesis) in response to PHA, OKT3, and Leu 4. In contrast, exogenous IL2 did not reverse CsA-mediated reductions in Con A-stimulated activation parameters. These findings indicate that CsA inhibits mitogen-induced expression of IL2R and TR, and for some mitogen systems, this inhibition appears, at least in part, to be secondary to decreased IL2 production.

Antibodies, Monoclonal↗

Unique pattern of interleukin 2 receptor expression by lymphocytes in response to anti-Leu 4 monoclonal antibody: relationship to monocyte accessory cell function.

The relationship of early interleukin 2 receptor (IL2R) expression to subsequent DNA synthesis by mitogen-stimulated human mononuclear cells (MC) was studied. For serial dilutions of a given mitogen, the percentage of lymphocytes expressing IL2R after 1 day of culture was plotted vs 3H-thymidine incorporation on day 3, and the IL2R value associated with a proliferative response of 50,000 counts per minute (IL2R-50K) determined. A mean IL2R-50K value of 7 characterized PHA, Con A, and OKT3 responses, while a higher mean value of 29 characterized anti-Leu 4(L4) responses. As tested in OKT3 and L4 systems, the addition of exogenous IL2 did not alter IL2R-50K values. Because both OKT3 and L4 recognize the lymphocyte CD3 antigen but react with different monocyte Fc receptors, the role of monocytes in producing elevated L4 IL2R-50K values was explored. MC from healthy L4 nonresponders (NR), induced to proliferate with L4 in the presence of responder (R) monocytes, also yielded an elevated mean IL2R-50K value of 31. In contrast, direct stimulation of R-MC, NR-MC, or NR-MC plus R monocytes by L4-coated sepharose beads produced lower mean IL2R-50K values of 12 or 13. Two-color cytofluorescence studies measuring IL2R and transferrin receptor (TR) on day 2 of culture revealed that most of the increase in IL2R+ cells in response to L4 was attributable to IL2R+TR-cells. These findings suggest that crosslinking of lymphocyte-bound soluble L4 by R monocytes leads to a uniquely elevated pattern of IL2R expression involving a disproportionate increase in the level of IL2R+TR-cells.

Antibodies, Monoclonal↗

Early activation marker expression to detect impaired proliferative responses to pokeweed mitogen and tetanus toxoid: studies in patients with AIDS and related disorders.

We tested the premise that measurement of interleukin 2 receptor (IL2R) and transferrin receptor (TR) can be used to assess proliferative responses to pokeweed mitogen (PWM) and tetanus toxoid (TT). Our study group consisted of patients with Human Immunodeficiency Virus (HIV) infection, including patients with acquired immunodeficiency syndrome (AIDS, n = 10), AIDS-related complex (n = 14), lymphadenopathy syndrome (n = 7), or homosexual men seropositive for HIV (n = 6). Controls were 40 healthy seronegative blood donors. IL2R and TR expression by stimulated mononuclear cells were assessed using specific monoclonal antibodies and flow cytometry, and results were analyzed using the 3H-thymidine assay for DNA synthesis as a standard for comparisons. For identifying low PWM responses, both the IL2R+ cell percent and the IL2R+ cell number (no.) per lymphocyte trigger region (a relative measure of IL2R+ cell no. per culture) on day 3 (72 h) were sensitive (greater than 90%) and specific (80%); day 3 TR+ cell no. was also sensitive (92%) and specific (100%). For detecting low TT-induced responses, day 7 IL2R+ cell no. proved the most sensitive (100%) and specific (78%) parameter. These findings indicate that cytofluorometric analysis of IL2R and/or TR expression is a reliable method for detecting impaired proliferative responses to PWM and TT in these patients. Such a method offers an attractive alternative to the regulatory and disposal problems associated with radioactivity in the conventional DNA synthesis assay, as well as providing insight to the mechanism(s) responsible for impaired proliferation.

Acquired Immunodeficiency Syndrome↗

Defective monocyte function in acquired immune deficiency syndrome (AIDS): evidence from a monocyte-dependent T-cell proliferative system.

T-cell proliferative responses to the mitogenic monoclonal antibody anti-Leu 4 were assessed in healthy controls, lymphadenopathy syndrome (LAS) patients, and acquired immune deficiency syndrome (AIDS) patients. While 19% of the control group showed low anti-Leu 4 responses (less than 12,000 cpm), 60% of the LAS patients, 71% of the AIDS-opportunistic infection patients, and 50% of the AIDS-Kaposi's sarcoma patients showed low responses. T-cell responsiveness in healthy low responders was greatly enhanced by the addition of monocytes from an anti-Leu 4 high responder (responder monocytes). We therefore sought to determine if the low-responder state in LAS and AIDS patients was also mediated by monocytes and, thus, correctable by the addition of responder monocytes. In the LAS low-responder group, the level of enhancement by healthy responder monocytes was similar to that observed for the healthy low-responder group. In the AIDS low-responder group, however, the level of enhancement was significantly lower than that observed in the healthy low-responder and LAS low-responder groups. These findings suggest that impaired proliferation to anti-Leu 4 in LAS patients may be due to a monocyte defect similar to the monocyte defect responsible for low anti-Leu 4 responses in healthy controls. AIDS patients, however, show additional defects in anti-Leu 4-induced proliferation that are not fully corrected by the addition of responder monocytes.

Acquired Immunodeficiency Syndrome↗

Multicentric angiofollicular lymph node hyperplasia (Castleman's disease) followed by Kaposi's sarcoma in two homosexual males with the acquired immunodeficiency syndrome (AIDS).

Two homosexual men with the acquired immunodeficiency syndrome (AIDS) who developed a multicentric variant of angiofollicular lymph node hyperplasia (AFLNH) (Castleman's disease) and Kaposi's sarcoma are reported. Both had diffuse adenopathy, splenomegaly, and a systemic inflammatory state. Both had an absolute increase in Leu 1+ lymphocytes, which was associated with markedly decreased Leu 3+ lymphocytes, markedly increased Leu-2+ lymphocytes, and a very low Leu 3/2 ratio. The lymphocytes of both patients had a normal blastogenic response to PHA. The lymphocytes of patient 1 had a poor response to autologous or allogenic cells in the mixed lymphocyte culture reaction. AFLNH represents another lymphoreticular complication of AIDS. Given the interrelationships between AFLNH, the development of Kaposi's sarcoma, and the aggressive clinical course seen in our two patients and those in the literature, the aggressive use of lymph node biopsy may be an important prognostic tool for the patient with the acquired immunodeficiency syndrome.

Acquired Immunodeficiency Syndrome↗

Antibody to human T-lymphotropic virus type III in wives of hemophiliacs. Evidence for heterosexual transmission.

To evaluate the risk of heterosexual transmission of the acquired immunodeficiency syndrome, lymphadenopathy, and infection with human T-lymphotropic virus type III (HTLV-III), we studied 42 hemophiliacs and their wives. By early 1984, 9 of the hemophiliacs had asymptomatic lymphadenopathy and 1 had the acquired immunodeficiency syndrome. Twenty-one hemophiliacs, including all 10 with clinically overt disease, had antibody to HTLV-III. None of the 42 wives had lymphadenopathy or the acquired immunodeficiency syndrome but 2 had HTLV-III antibody. One of these women had evidence of immunologic dysfunction with a markedly reduced T-helper/suppressor cell ratio. The husbands of these 2 women both had HTLV-III antibody, but neither had overt acquired immunodeficiency syndrome-related disease. Thus, as of early 1984, the prevalence of HTLV-III antibody in wives of hemophiliacs seropositive for HTLV-III was 9.5% (2 of 21). We conclude that transmission of HTLV-III occurs between hemophiliacs and their heterosexual partners.

Acquired Immunodeficiency Syndrome↗

Influence of racial background on the distribution of T-cell subsets and Leu 11-positive lymphocytes in healthy blood donors.

As part of a study to define the factors affecting the distribution of lymphocyte subpopulations in healthy blood donors, we have measured lymphocyte surface markers in various racial groups. Markers tested were T3 (all T cells), T4A (T helper cells), T8 (T suppressor cells), and Leu 11 (natural killer cells). Racial groups included three Asian groups (Chinese, Japanese, Other Orientals) and three non-Asian groups (Caucasians, Hispanics, American Blacks). The mean percentage of T3 + cells and T4A + cells were significantly lower in Asians compared with non-Asians, while T8 levels did not differ. These changes resulted in a significantly lower mean T4A:T8 ratio in Asians compared with non-Asians. The mean percentage of Leu 11 + cells was higher in Asians compared with non-Asians. Within the Asian group, Chinese had a higher mean Leu 11 + value than the other two Asian groups combined. Further, pairwise comparisons showed that Chinese had a significantly higher mean Leu 11 + value compared with each of the other five racial groups. This increased mean Leu 11 + level in the Chinese group reflected a distinct cluster of high values for about half the subjects. These findings show that racial background should be a major consideration when defining the normal range for lymphocyte subpopulations detected by surface markers.

Adult↗

Distinctive lymphocyte subpopulation abnormalities in patients with congenital coagulation disorders who exhibit lymph node enlargement.

The majority of patients with congenital clotting disorders who use clotting factor concentrate exhibit lymphocyte subpopulation abnormalities. A subset of these patients develop lymph node enlargement (LNE), part of the spectrum of clinical disease associated with the acquired immune deficiency syndrome (AIDS). It is therefore important to determine if these patients with LNE exhibit specific immune alterations suggestive of early infection with the AIDS agent. We used one- and two-color immunofluorescence to distinguish the lymphocyte subpopulation alterations associated with concentrate use from those associated with LNE. Patients who use concentrate had elevated levels of Leu-2+ (T suppressor phenotype) cells and Leu-7+ (phenotype of some natural killer) cells. These increased levels were largely caused by a dramatic (2.6-fold) increase in the number of lymphocytes co-expressing Leu-2 and Leu-7 (2+7+). A dose-response effect between amount of concentrate infused during the preceding year and level of 2+7+ cells was observed. Concentrate recipients, as a group, also showed increased levels of T cells expressing Dr antigen (T+Dr+ phenotype, characteristic of activated or immature T cells) and cells expressing the T10 antigen (phenotype of some null cells and activated/immature T cells). Patients with LNE showed a further increase in T10+ cells as well as a distinctive decrease in Leu-3+ (T helper phenotype) lymphocytes. All LNE patients exhibited either low Leu-3+ levels, high T10+ levels, or both. Thus, concentrate use was associated with increased levels of Leu-2+ (particularly 2+7+) cells and T+Dr+ cells, whereas LNE was associated with decreased levels of Leu-3+ cells and high levels of T10+ cells.

Acquired Immunodeficiency Syndrome↗

HLA studies in acquired immune deficiency syndrome patients with Kaposi's sarcoma.

To investigate the possible contribution of genetic susceptibility to Kaposi's sarcoma associated with acquired immune deficiency syndrome (AIDS-KS), 21 patients were typed for HLA-A, B, C, and DR antigens. Significantly increased frequencies of HLA-Aw23, and HLA-Bw49 antigens were observed in the Caucasian AIDS-KS group. In this same group, the frequencies of HLA-DR5 and HLA-Bw44 antigens were increased at the P less than 0.1 level. Increased frequencies of HLA-A29 and HLA-Cw4 antigens and a decreased frequency of HLA-B8 antigen were also noted, but with P greater than 0.1, in the Caucasian AIDS-KS group.

Acquired Immunodeficiency Syndrome↗