Weishui Y. Weiser

Modulation of eosinophil cytotoxicity by blood mononuclear cells from healthy subjects and patients with chronic Schistosomiasis mansoni

Human blood mononuclear cells in culture release a factor(s) that markedly enhances eosinophil cytotoxicity. This factor(s) stimulates eosinophils to kill Schistosoma mansoni larvae at low antibody concentrations and cell/target ratios. A study of the mononuclear cells of 78 subjects with chronic schistosomiasis mansoni and 33 controls suggests that the production of eosinophil cytotoxicity enhancing activity (ECEA) is suppressed in most patients with S. mansoni infections. Suppression of ECEA production was not observed, however, with cells from many patients with heavy infections, including patients with hepatosplenomegaly. The possible role of ECEA in the development of pathology is discussed.

Human recombinant migration inhibitory factor activates human macrophages to kill tumor cells

A recombinant form of human migration inhibitory factor (rMIF) obtained from COS-1 cells transfected with MIF-specific cDNA is able to activate cultured human peripheral blood monocytes and monocyte-derived macrophages, in a dose-dependent manner to become cytotoxic for tumor cells in vitro. The cytotoxicity exhibited by macrophages treated with rMIF is > or = 30% above that of cells incubated with control supernatants or with media and peaks 72 hr after the addition of tumor targets. rMIF also induces macrophages to produce tumor necrosis factor (TNF-alpha) and interleukin-1 beta (IL-1 beta). These results demonstrate that rMIF is able to modulate macrophage functions and plays a role in cell-mediated immune response.

Generation of human hybridomas producing migration inhibitory factor (MIF) and of murine hybridomas secreting monoclonal antibodies to human MIF

Human T-cell hybridomas were established by hybridization of concanavalin A (Con A)-stimulated human peripheral blood T lymphocytes with cells from a 6-thioguanine-resistant, aminopterin-sensitive mutant line designated CEM-WH4, derived from the continuously growing human T cell line, CEM. High levels of MIF activity were demonstrated in the supernatants of two hybridoma lines, T-CEMA and T-CEMB but not of CEM-WH4 when stimulated with phorbol myristate acetate and phytohemagglutinin. In comparison, MIF derived from Con A-stimulated peripheral blood mononuclear cells showed 100 times less activity. Upon isoelectrofocusing, MIF activity of T-CEMB was found exclusively between pH 4.6 and 5.3 whereas MIF derived from T-CEMA showed heterogeneity with a major peak of MIF recovered at pH 4.6-5.3 and a minor peak at pH 2.4-3.3. These molecules, however, were all found to have an apparent MW of 68,000 and were resistant to trypsin. Most of these characteristics are in accordance with second day pH 3- and pH 5-MIF derived from peripheral blood mononuclear cells. When spleen cells from BALB/c mice immunized with T-CEMB-MIF were used to fuse with NS-1 mouse myeloma cells, nine hybridomas secreting antibodies to human MIF were obtained. Clone D112 which demonstrated the highest MIF-neutralizing activity was found to neutralize MIF derived from T-CEMA, peripheral blood mononuclear cells, and a T cell line, Mo.

An acidic lymphokine distinct from interferon-γ inhibits the replication of herpes simplex virus in human pulmonary macrophages

Supernatants from concanavalin A-stimulated human peripheral blood mononuclear cells were fractionated by gel filtration and isoelectric focusing. A fraction with an isoelectric point of 2.2-3.3 containing macrophage migration inhibition factor activity inhibited the replication of herpes simplex virus type 1 in human pulmonary macrophages and U937 cells. This fraction did not inhibit the replication of herpes simplex virus in human fibroblasts. Moreover, the ability of this lymphokine fraction to inhibit viral growth in macrophages was not neutralized by antibody against interferon-gamma. These findings identify a macrophage specific antiviral lymphokine which is distinct biochemically and immunologically from interferon-gamma.

Lymphokines and macrophages.

It is a pleasure and a privilege to be here today to honor Lewis Thomas. As I look out on this distinguished audience and see so many good friends, it brings on an attack of nostalgia for the early sixties on the sixth floor of Building D in Bellevue. Those years with Jerry and Lew were some of the most exciting and satisfying of my career. The sixties may not have been golden years for the country, but it certainly was a golden time to start to work in research, particularly at New York University. Perhaps it was a lucky conjoining of time and place, but, in any event, one remembers above all the everyday generosity, openness, and civility of working life. In retrospect, it is clear that what made it that way was the people, many of them attracted or held by the magnet of Lewis Thomas. There never seemed to be anxiety about grant funds, but I know now that a lot of work got done on not very much money. No one pressured us to publish; in fact, I came to New York University in 1961 and my first papers came out in 1964. There was not much space and there were lots of people. I have always suspected that my lab in Jerry’s unit and Peter Elsbach’s lab two doors down were actually closets. We did not make up for lack of space with lots of equipment either. Sharing was not the polite thing to do, it was the only thing. Sharing and fixing: one could, and did, find Saul Farber at seven o’clock at night fixing the ancient Bellevue autoclave. But, what we did have, above all and in plenty, was discussion, mainly in the hallways because no one had an office in which to hide. And, often, at the end of the day, Lew would pop into the lab to ask what had happened in the latest experiment. You could rely on getting four or five ideas from him as he thought about the possibilities. All would be brilliant, at least two would be undoable (though we often tried to do them anyway), but usually one would add something new and exciting to the next day’s work. The work I will review here started when Lewis Thomas returned from a visit to John Vaughan in Rochester bringing back capillary tubes and Mackaness-type chambers. When I came to New York University, Salah Al-Askari and I set up and modified the inhibition of migration system so that it could be used routinely with guinea pig cells. The work in this area proceeded like a hobby, as the main thrust was on transfer factor. Indeed, Jerry hoped that the inhibition of migration technique could be used

Partial purification and characterization of a human lymphokine which induces antileishmanial activity in mouse macrophages

Human blood mononuclear cells stimulated in vitro with concanavalin A secrete a lymphokine which activates mouse macrophages to kill Leishmania enriettii. Supernatants of cells cultivated for 1 day and for 2 days were analyzed for this activity after G-100 gel filtration and isoelectrofocusing. First day antileishmanial activity was found in a MW range of 23,000 with an isoelectric point of 3.6 to 4.0. Second day antileishmanial activity eluted in a peak in the MW range of 23,000 to 65,000 with an isoelectric point of 4.0 to 4.3. This activity could be completely separated from migration-inhibitory factor (MIF) after isoelectrofocusing in first day and in second day supernatants. Antileishmanial activity could be separated from interferon-gamma in first day, but not in second day supernatants.

Dissociation of human interferon-gamma-like activity from migration-inhibition factor☆

Supernatants harvested from concanavalin A-stimulated human peripheral mononuclear cells after 24 hr of incubation contain one interferon species similar to human interferon-gamma (IFN-gamma) with a pI of 4.6-5.3 (first day pH 5 IFN-gamm). In contrast, during the subsequent 24 hr of incubation two species with properties of IFN-gamma are produced with pI of 3.6-4.0 (second day pH 4 IFN-gamma) and 4.6-5.6 (second day pH 5 IFN-gamma), respectively. First day pH 5 IFN-gamma and second day pH 5 IFN-gamma have been found to differ on the basis of trypsin sensitivity. This pattern of polymorphism is similar to the pattern previously described for human migration-inhibitory factor (MIF) which can be separated into first day pH 5 MIF, second day pH 3 MIF, and second day pH 5 MIF. However, IFN-gamma-like species can be differentiated from MIF biochemically and antigenically. Fractions with second day pH 4 IFN-gamma have no MIF activity and fractions with second day pH 3 MIF contain no IFN activity. In addition, first and second day pH 5 MIF, which also contain IFN-gamma activity, can be separated from the latter by precipitation as well as neutralization with polyclonal and monoclonal anti-human MIF antibodies.

Identification and Characterization of a Non-Interferon Antileishmanial Macrophage Activating Factor (Antileishmanial MAF)

A non-interferon lymphokine elaborated from PHA and Con A-stimulated human T-cell hybridoma, T-CEMA, has been found to activate monocyte-derived macrophages for the intracellular killing of L. donovani (antileishmanial MAF). This T-cell hybridoma derived antileishmanial MAF which has an apparent mw of 65,000 and pI of 5.3-5.6, contains neither antiviral activity nor colony stimulating activity. Furthermore, antileishmanial MAF is not neutralized by anti-MIF, anti-IFN-gamma or anti-GM-CSF antibodies.

Antigen-dependent heterogeneity of human migration inhibitory factor

Human migration inhibitory factor (MIF) produced by peripheral blood mononuclear cells stimulated with purified protein derivative, tetanus toxoid, streptokinase-streptodornase, or Candida albicans antigen was analyzed by gel filtration and isoelectrofocusing. In all cases, supernatants harvested after a 24-hr exposure of the mononuclear cells to the antigen yielded only one MIF species with an isoelectric point of 5. In contrast, isoelectrofocusing of supernatants obtained from cells exposed to the antigen for an additional 24 hr demonstrated that different antigens induce the elaboration of different MIF species. Streptokinase-streptodornase and tetanus toxoid induced the production of one MIF species with an isoelectric point of 5 (pH 5-MIF). Stimulation of cells with Candida antigen elaborated a MIF species with an isoelectric point of 3 (pH 3-MIF). In contrast, stimulation of cells with purified protein derivative induced the production of both pH 3-MIF and pH 5-MIF.