Nanoparticles — particles in the size range 1–100 nm — are emerging as a class of therapeutics for cancer. Early clinical results suggest that nanoparticle therapeutics can
show enhanced efficacy, while simultaneously reducing side effects, owing to properties such as more targeted localization in tumours and active cellular uptake. Here, we
highlight the features of nanoparticle therapeutics that distinguish them from previous anticancer therapies, and describe how these features provide the potential for
therapeutic effects that are not achievable with other modalities. While large numbers of preclinical studies have been published, the emphasis here is placed on preclinical and clinical studies that are likely to affect clinical investigations and their implications for advancing the treatment of patients with cancer.

Nanoparticle therapeutics: an emerging treatment modality for cancer

A murine monoclonal antibody specific for calf intestinal alkaline phosphatase has been prepared and used in an unlabeled antibody bridge technique for labeling monoclonal antibodies. This procedure--the alkaline phosphatase monoclonal anti-alkaline phosphatase (APAAP) method--gives excellent immunocytochemical labeling of tissue sections and cell smears, comparable in clarity and intensity to that achieved with immunoperoxidase labeling. If the enzyme label is developed with a naphthol salt as a coupling agent and Fast Red or hexazotized new fuchsin as a capture agent, a vivid red reaction product is obtained which is very easily detected by the human eye. For this reason the APAAP technique was found particularly suitable for labeling cell smears (for both cytoplasmic and surface-membrane antigens) and for detecting low numbers of antigen-bearing cells in a specimen (e.g., carcinoma cells in a malignant effusion). It was found possible to enhance the intensity of the APAAP labeling reaction substantially by repeating the second and third incubation steps (i.e., the unlabelled "bridge" antibody and APAAP complexes). The APAAP technique was superior to immunoperoxidase labeling for staining tissues rich in endogenous peroxidase, and could be used in conjunction with immunoperoxidase methods for double immunoenzymatic staining. The method was also applicable to the detection of antigenic molecules following their electrophoretic transfer from SDS-polyacrylamide gels to nitrocellulose sheets ("immunoblotting").

Immunoenzymatic labeling of monoclonal antibodies using immune complexes of alkaline phosphatase and monoclonal anti-alkaline phosphatase (APAAP complexes).

A revised European-American classification of lymphoid neoplasms: a proposal from the International Lymphoma study group

Background DNA fragments that appeared to belong to an unidentified human herpesvirus were recently found in more than 90 percent of Kaposi's sarcoma lesions associated with the acquired immunodeficiency syndrome (AIDS). These fragments were also found in 6 of 39 tissue samples without Kaposi's sarcoma, including 3 malignant lymphomas, from patients with AIDS, but not in samples from patients without AIDS. Methods We examined the DNA of 193 lymphomas from 42 patients with AIDS and 151 patients who did not have AIDS. We searched the DNA for sequences of Kaposi's sarcoma–associated herpesvirus (KSHV) by Southern blot hybridization, the polymerase chain reaction (PCR), or both. The PCR products in the positive samples were sequenced and compared with the KSHV sequences in Kaposi's sarcoma tissues from patients with AIDS. Results KSHV sequences were identified in eight lymphomas in patients infected with the human immunodeficiency virus. All eight, and only these eight, were body-cavity–based lymphomas — that...

Kaposi's Sarcoma–Associated Herpesvirus-Like DNA Sequences in AIDS-Related Body-Cavity–Based Lymphomas

Unmutated Ig V(H) genes are associated with a more aggressive form of chronic lymphocytic leukemia.

A tissue processing instrument (the Histokinette) was modified by the addition of an electronic timing device which allows an immunocytochemical staining technique (the APAAP method) to be performed as a semiautomated procedure. After incubation with primary monoclonal antibodies (applied by hand) slides (up to 72 in a batch) are placed in racks and cycled through tanks of reagents, comprising anti-mouse Ig followed by APAAP complexes with intervening timed draining and washing stages. This semiautomated process gave consistent staining results and offered considerable savings in time compared with conventional methods. The same reagent baths were used over four months on an almost daily basis without deterioration in staining intensity, and consequently the calculated overall cost of the staining procedure was less than if the reagents had been applied by hand and then discarded. The machine is now into its eleventh month of operation; the reagents have been changed twice. It is suggested that this approach, because of savings in time and increased consistency, may be an attractive technique for the routine immunocytochemical staining of slides, and that the nature of the APAAP method is particularly suitable for automation as the necessary reagents can be produced at low cost.

https://jcp.bmj.com/content/jclinpath/42/1/106.full.pdf

Automation of APAAP immunocytochemical technique.

Detection of 14;18 chromosomal translocation in paraffin-embedded lymphoma tissue.

The present paper describes two new MoAbs, GHI/75 and VMP55, which were raised against a glycoprotein enriched lysate of hairy cell leukaemia. These antibodies recognized a new antigen of 72 kD (unreduced) and 83 kD (reduced) molecular weight. GHI/75 and VMP55 gave very strong staining of plasma cells, moderate labelling of circulating B cells but only weak staining of monocytes, some tissue macrophages and lymphoid cells. Neither antibody reacted with neutrophils or any non-haematopoietic cells. Both antibodies, however, strongly labelled the tumour cells in hairy cell leukaemia, multiple myeloma, plasmacytoma and lymphoplasmacytic lymphomas. No staining was seen of the neoplastic cells in Hodgkin's disease, myeloid leukaemia or T cell lymphomas. The two antibodies, GHI/75 and VMP55, may be of value in the differential diagnosis of hairy cell leukaemias and plasma cell neoplasms. In addition, the ease with which their antigen can be purified provides the possibility for a detailed study of this molecule.

A 72‐kD B cell‐associated surface glycoprotein expressed at high levels in hairy cell leukaemia and plasma cell neoplasms

Cell smears from serous effusions containing large numbers of lymphoid cells were stained by the alkaline phosphatase-anti-alkaline phosphatase technique with a panel of monoclonal antibodies, including anti-B and anti-T cell antibodies and anti-HLA-DR. Samples from 17 patients with lymphoproliferative disorders--such as chronic lymphocytic leukaemia and non-Hodgkin's lymphoma--and from 19 patients who had no evidence of lymphoid neoplasia--for example, cases of carcinoma, cardiac failure--were investigated. The majority of lymphoid cells in reactive effusions were T cells, which lacked HLA-DR and showed a marked excess of helper/inducer cells (mean helper to suppressor ratio of 3 X 5). In contrast, lymphoid cells in samples from nine cases of B cell neoplasia were positive for B cell antigen and HLA-DR. In a further four B cell neoplasms most lymphoid cells were reactive T cells. Two cases of T cell lymphoid leukaemia could also be characterised by immunocytochemical staining, both being classified as T helper cell neoplasms. Labelling was performed on routinely prepared, air dried cell smears, which could be stored in the unfixed state for long periods before staining. The technique may therefore be of use in many clinical cytology laboratories for the diagnosis of effusions containing numerous lymphoid cells.

https://jcp.bmj.com/content/jclinpath/38/6/608.full.pdf

Immunocytochemical staining of T and B lymphocytes in serous effusions.

SUMMARY

It has been reported that the monoclonal antibody BE2, raised against leukaemic T cells, reacts specifically with malignant lymphoid cells and represents a valuable reagent for the early identification of cutaneous T-cell lymphomas. To test this hypothesis, a comprehensive range of nodal and cutaneous biopsies have been examined immunohistologically using single and double immunoenzymatic and immunofluorescent staining methods. BE2 showed a broad range of reactivity, consistently labelling normal endothelial cells, B-lymphocytes in mantle and marginal zones, T-lymphocytes in the paracortex of lymph nodes and medulla of thymus, as well as a variety of different macrophage types, including Langerhans cells and dermal macrophages. Furthermore, although BE2-positive T-lymphocytes were most frequent in malignant lymphomas, they were also found in four of 19 benign dermatoses. We conclude that BH2 is neither T-cell nor tumour-cell specific, and that use of this reagent on tissue sections is unlikely to improve the diagnosis of cutaneous lymphomas.

D Y Mason

Papers

Automation of APAAP immunocytochemical technique.

Detection of 14;18 chromosomal translocation in paraffin-embedded lymphoma tissue.

A 72‐kD B cell‐associated surface glycoprotein expressed at high levels in hairy cell leukaemia and plasma cell neoplasms

Immunocytochemical staining of T and B lymphocytes in serous effusions.

Immunohistological reactivity pattern of the anti‐cutaneous T‐cell lymphoma antibody BE2