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A Nikaein

Publications and source records attributed to A Nikaein.

26 records · Page 2Linked to original sources
PubMed1988

The autologous mixed lymphocyte response: isolation of mononuclear cell populations by counterflow centrifugal elutriation.

We have used counterflow centrifugal elutriation (CCE) to isolate cell populations for an autologous mixed lymphocyte response (AMLR). Enriched T lymphocyte and monocyte populations were obtained rapidly without the need for cells to first form rosettes with sheep RBC (T cells) or adhere to plastic (monocytes). In 16 separate experiments, peripheral blood (PB) was separated by CCE (9) and/or a plastic adherence and nylon wool column method (9). Viability by all methods was greater than 95% CCE yielded greater than 97% lymphocytes in F20 and greater than 90% lymphocytes in F26. Cells obtained after passage through nylon wool yielded greater than 90% lymphocytes. Both CCE (F34) and plastic adherence techniques yielded greater than 75% monocytes. Similar AMLR response was obtained using either cell separation method. We conclude that mononuclear cells isolated by CCE are responsive in the AMLR and yield comparable data to other more tedious techniques.

Adult↗
PubMed1987

Development of class I-specific helper-inducer T-cell clone.

A unique alloreactive human helper-inducer T-cell clone which reacts with the class I HLA antigen was characterized. The clone was derived from a mixed lymphocyte culture between cells from a HLA-A2-; B35,w51; Bw4,Bw6; Cw4,-; DR1,4; DQw1,-; DRw53 responder and a HLA-A2,3; B7,14; Bw6; Cw8,-; DR7,-; DQw2,w3; DRw52 stimulator. When screened against a panel of stimulator cells, this clone was found to have a specificity towards a stimulator HLA-B14 and consisted entirely of Leu-4, Leu-3, and 4B4 positive T cells, which is a T helper-inducer phenotype. Using monoclonal antibodies directed towards various monomorphic class I and II HLA epitopes in an inhibition experiment, it was found that both monoclonal antibodies w6/32 and 4E (recognizing class I monomorphic and HLA-B epitopes, respectively) inhibited proliferation. However, monoclonal antibodies BBm.1 and L227 (directed against beta 2-microglobulin and Ia-like molecule, respectively) had no inhibitory effect. Functional evaluation of this clone demonstrated helper activity on the proliferation of MLC response. The helper-induction effect on MLC cultures remained intact following irradiation of the clone for either 500 or 2000 rad suggesting that helper function of the clone was radiation resistant. The helper activity of this clone was MHC nonrestricted since it enhanced proliferation of the original responder and stimulator MLC as well as third and fourth party individuals. By CTLL cell line proliferation assay, this clone was found to release IL-2. When assayed (day 1 to 7) for class II HLA products expression following stimulation, HLA-DRw53 was consistently expressed by the clone. However, HLA-DR1, DQw1 were found to be expressed simultaneously on day 2 through day 7 and HLA-DR4, DQw3 on day 2 and 3. These data demonstrate, for the first time, the generation of a class I specific helper-inducer T-cell clone in MLC response.

Antibodies, Monoclonal↗
PubMed1984

Heterogeneity of human T-lymphocyte clones generated from autologous mixed-lymphocyte cultures.

To assess the heterogeneity of T cells activated during the autologous mixed-lymphocyte reaction (AMLR), a cloning procedure based on the soft agar colony assay was developed. Supernatants of allogeneic MLR cultures were used as a source of interleukin 2 (IL-2) to generate two types of colonies: upper and lower colonies. Both types of colonies were expanded in long-term cultures using supernatants of phytohemagglutinin (PHA)-activated lymphocyte cultures. Cloned cells underwent secondary proliferation when stimulated by autologous monocytes, although certain clones also responded to autologous B cells. Most autoactivated clones expressed the serological determinants of HLA-DR, MB, and MT and were OKT3+, OKT4+, OKT8-. They did not induce cytolysis of autologous monocytes, B lymphoblasts, or PHA blasts nor did they express natural killer-like activity toward K562 cells. Several autoactivated clones (irradiated with 500 R) expressed helper activity, shown by an enhancing effect on AMLR proliferation. Furthermore, many irradiated clones were capable of inducing proliferation of autologous T cells in the absence of accessory cells. These observations suggest that autoactivated clones generated from soft agar colonies may interact with autologous T lymphocytes.

Adult↗
PubMed1984

Monoclonal antibody analysis of responder and stimulator cells in the human autologous mixed lymphocyte reaction.

Responder and stimulator cell subpopulations in the autologous mixed lymphocyte reaction (AMLR) were determined with the OK series of monoclonal antibodies. Mitomycin-C-treated, monocyte-enriched cell populations were used as stimulator cells in the AMLR. Treatment of these monocytes with either OKM and/or OKI monoclonal antibodies and complement resulted in a marked loss of ability of these cells to act as stimulators in the AMLR. Removal of OKT3+ and OKT4+ cells diminished the proliferative responses of AMLR cultures. Interaction of T cells with autologous monocytes resulted in generation of cells capable of suppressing both MLR and AMLR cultures. The suppressor activity of these cells was diminished by treatment with OKI , OKT4 or OKT8 monoclonal antibodies. No cytotoxic activity to autologous or allogeneic monocytes was observed. Additional studies showed an increased number of OKT9 + and OKI + as well as OKT8+ T cells in the AMLR responder cell population. This study indicates that cultures of T lymphocytes with autologous monocytes yield T cell subset(s) which suppress MLR and AMLR reactivity.

Antibodies, Monoclonal↗
PubMedDate not supplied

Effect of major dietary modifications on immune system in patients with breast cancer: a pilot study.

A pilot study was conducted to evaluate the effect of diet on immune function in nine premenopausal, post-therapy patients with breast cancer. The patients were instructed on following the American Cancer Society dietary guidelines and were told to do so from day 0 to day 28. These guidelines recommend a high-fiber, low-fat diet. On day 29, the patients continued the diet but included fish high in omega-3 fatty acids until day 56. Twenty-four-hour urine and blood samples, and 3-day diet records were obtained on days 0, 28, and 56. The following parameters were monitored: lymphocyte subsets, T-cell function (proliferation and cytolytic response), and urinary prostaglandin E2 (PGE2). Results throughout the study suggested a benefit from decreasing dietary fat intake, and increasing fish intake. Helper T-cell (CD4) percentage increased from day 0 to days 28 and 56 (P = 0.048). Cytotoxic/suppressor T-cell (CD8) percentage decreased from day 0 to days 28 and 56 (P = 0.002). The CD4/CD8 cell ratio increased by days 28 and 56 (P = 0.0004). The proliferation of CD4 cells increased from day 0 to days 28 and 56 (P = 0.005). Significant changes were not found in the cytolytic activity of T cells, natural killer cells, total T and B cells, or urinary prostaglandin E2. Results suggest that patients with breast cancer may benefit from following American Cancer Society dietary guidelines and consuming cold-water ocean fish.

Adult↗