Heat shock protein (HSP) preparations derived from cancer cells and virus-infected cells have been shown previously to elicit cancer-specific or virus-specific immunity. The immunogenicity of HSP preparations has been attributed to peptides associated with the HSPs. The studies reported here demonstrate that immunogenic HSP–peptide complexes can also be reconstituted in vitro. The studies show that (a) complexes of hsp70 or gp96 HSP molecules with a variety of synthetic peptides can be generated in vitro; (b) the binding of HSPs with peptides is specific in that a number of other proteins tested do not bind synthetic peptides under the conditions in which gp96 molecules do; (c) HSP–peptide complexes reconstituted in vitro are immunologically active, as tested by their ability to elicit antitumor immunity and specific CD8+ cytolytic T lymphocyte response; and (d) synthetic peptides reconstituted in vitro with gp96 are capable of being taken up and re-presented by macrophage in the same manner as gp96– peptides complexes generated in vivo. These observations demonstrate that HSPs are CD8+ T cell response–eliciting adjuvants.

One hundred patients with tuberculous mastitis were referred to the Tata Memorial Hospital, a cancer center, with a clinical diagnosis of malignancy. This study identifies the possible causes of misdiagnosis and reviews the management of these patients. A lump in the breast with or without ulceration was the commonest presentation, the others being diffuse nodularity and multiple sinuses. Concomitant axillary lymph nodes were found in one-third of the patients. Tuberculosis lesions such as nodular mastitis, disseminated mastitis, and sclerosing lesions clinically mimicked a fibroadenoma, carcinoma, and fibrocystic mastitis depending on the mode of presentation. A young, multiparous, lactating woman with a lesion should arouse the suspicion of tuberculous mastitis, although pretherapeutic pathologic confirmation of a benign disease is mandatory. Mammography, fine-needle aspiration cytology, and excision biopsy for this purpose are successful in 14%, 12%, and 60% of cases, respectively. Acid-fast bacilli were identified in 12% patients. All patients received antituberculous chemotherapy, and 14% patients required simple mastectomy, due to either lack of response to chemotherapy (10%) or large painful, ulcerative lesions involving the entire breast (4%). Axillary dissection was performed in only 8% patients with large ulcerated axillary nodes. All patients, followed for a minimum of 2 years, were free of disease after therapy.

Mice immunized with optimal doses of autologous tumor–derived gp96 resist a challenge with the tumor that was the source of gp96. Immunization with quantities of gp96 5–10 times larger than the optimal dose does not elicit tumor immunity. This lack of effect is shown to be an active, antigen-specific effect, in that immunization with high doses of tumor-derived gp96, but not normal tissue–derived gp96, downregulates the antitumor immune response. Furthermore, immunization with fractionated doses of gp96 elicits the same kind and level of response as elicited by a single dose equivalent to the total of the fractionated doses. This is true of  the tumor-protective doses as well as the high downregulatory doses of gp96. The downregulatory activity can be adoptively transferred by CD4+ but not CD8+ T lymphocytes from mice immunized with high doses of gp96. These observations indicate that immunization with gp96 induces a highly regulated immune response that, depending upon the conditions of immunization, results in tumor immunity or downregulation.

Injury causes tissue breakdown, which releases large quantities of intracellular contents into the extracellular space. Some of these materials are well-established activators of the immune system and include heat shock proteins (HSPs), uric acid, nucleotides, High Mobility Group Box-1 protein (HMGB-1), and DNA. Here, we show that in vivo delivery of HSPs into BALB/cJ mice with full-thickness wounds accelerates the rate of wound closure by 60% as compared with control-treated mice. The onset is rapid and the effect is sustained, dose dependent, and protein specific. Adoptive transfer of RAW264 macrophages pretreated with HSP70 into naïve recipients with a wound transfers the HSP-mediated effect on the rate of wound closure. Further, we demonstrate that part of the mechanism by which HSP70 accelerates wound closure is through the stimulation of macrophage-mediated phagocytosis of wound debris. Disabling the HSP70-mediated enhancement of phagocytosis abrogates the HSP-mediated acceleration of the healing process. These findings create two opportunities: one, therapeutic, wherein HSP70 could be used in the clinical management of wounds; and two, pathophysiologic, to decode signals by which the host defenses recognize and respond to injury.

Immunization with heat-shock protein (HSP) gp96 elicits protective immunity to the cancer or virus-infected cells from which it is derived. Low doses of gp96 generate immunity, while doses 10 times the immunizing dose do not. We show here that injection of high doses of gp96 generates CD4(+) T cells that down-regulate a variety of ongoing immune responses. Immunization with high doses of gp96 prevents myelin basic protein- or proteolipid protein-induced autoimmune encephalomyelitis in SJL mice and the onset of diabetes in non-obese diabetic mice. The suppression of immune response can be adoptively transferred with CD4(+) cells and does not partition with the CD25 phenotype. The immunomodulatory properties of gp96 (and possibly other HSP) may be used for antigen-specific activation or suppression of cellular immune responses. The latter may form the basis for novel immunotherapies for autoimmune diseases.

The extracellular presence of endotoxinfree heat shock protein 70 (HSP70) enhances the rate and capacity of macrophage-mediated phagocytosis at 6 times the basal rate. It is protein-specific, doseand time-dependent and involves the internalization of inert microspheres, Grampositive and -negative bacteria and fungi. Structurally, exogenous HSP70 binds the macrophage plasma membrane, specifically on its lipid raft-microdomain. Disruption of lipid rafts, HSP70-LR interaction, or denaturing HSP70 abrogates the HSPmediated increase in phagocytosis. Further, HSP70-mediated phagocytosis directly enhances the processing and presentation of internalized antigens via the endocytic MHC class-II pathway to CD4 ؉ T lymphocytes. Modulating the HSP70-LR interaction presents an opportunity to intervene at the level of hostpathogen interface: a therapeutic tool for emerging infections, especially when conventional treatment with antibiotics is ineffective (antibiotic resistance) or unavailable (rapidly spreading, endemic). These results identify a new role for HSP70, a highly conserved molecule in stimulating phagocytosis: a primordial macrophage function, thereby influencing both innate and adaptive immune responses. (Blood.

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Fifty consecutive patients with sacrococcygeal chordomas treated during 1941-1991 at the Tata Memorial Hospital in India were studied retrospectively. Pain was the commonest presenting symptom (82%). An average time lapse of 14 months between the onset of pain and definitive diagnosis emphasizes the importance of a high index of suspicion and prompt use of sophisticated imaging techniques leading to an early diagnosis. All patients underwent a partial sacrococcygectomy, through a sacral approach in 22 patients (44%) and an abdominosacral approach in 28 (56%). Postoperative complications included urinary incontinence (14%), rectal incontinence (6%), hemorrhage (4%), and rectal injury (2%). Radiotherapy offered significant pain relief to patients with widespread recurrence. A total of 38 patients were ambulatory, and 12 needed support. The average disease-free survival was 63 months, and the overall survival was 7 years. Aggressive resection through a combined abdominosacral approach offers the best results. Because postrecurrence salvage rates are poor, the primary surgery must be complete and curative.