Kohli-Pamnani A, Rodenas M, Duah BA, Ansah-Twum J, Blessing M, et al.
JBJS case connector •
A 65-year-old woman with alpha-gal syndrome (AGS) required total hip arthroplasty. Laboratories revealed galactose-alpha-1,3-galactose immunoglobulin E 0.4 kU/L (abnormal ≥ 0.1 kU/L). In the absence of published guidelines for perioperative management of AGS, we used a pragmatic approach incorporating omalizumab. Perioperative management of AGS incorporated omalizumab injections, avoidance of high-risk medications and surgical materials containing mammalian derivatives, and pretreatment (corticosteroids, H1 and H2 antihistamines, montelukast). She tolerated hip arthroplasty without perioperative anaphylaxis or AGS symptoms by 4 months of follow-up. High-risk medications include propofol (may contain glycerol), analgesics (gelatin, magnesium stearate, lactose), and heparin (porcine, bovine).
Ticks are hematophagous arthropods that transmit disease-causing pathogens worldwide. Tick saliva deposited into the tick-bite site is composed of an array of immunomodulatory proteins that ensure successful feeding and pathogen transmission. These salivary proteins are often glycosylated, and glycosylation is potentially critical for the function of these proteins. Some salivary glycans are linked to the phenomenon of red meat allergy - an allergic response to red meat consumption in humans exposed to certain tick species. Tick salivary glycans are also invoked in the phenomenon of acquired tick resistance wherein non-natural host species exposed to tick bites develop an immune response that thwarts subsequent tick feeding. This review dwells on our current knowledge of these two phenomena, thematically linked by salivary glycans.
DuPont M, Visca H, Moshnikova A, Engelman DM, Reshetnyak YK, et al.
Frontiers in bioengineering and biotechnology •
Targeted antigen delivery allows activation of the immune system to kill cancer cells. Here we report the targeted delivery of various epitopes, including a peptide, a small molecule, and a sugar, to tumors by pH Low Insertion Peptides (pHLIPs), which respond to surface acidity and insert to span the membranes of metabolically activated cancer and immune cells within tumors. Epitopes linked to the extracellular ends of pH Low Insertion Peptide peptides were positioned at the surfaces of tumor cells and were recognized by corresponding anti-epitope antibodies. Special attention was devoted to the targeted delivery of the nine residue HA peptide epitope from the Flu virus hemagglutinin. The HA sequence is not present in the human genome, and immunity is readily developed during viral infection or immunization with KLH-HA supplemented with adjuvants. We tested and refined a series of double-headed HA-pHLIP agents, where two HA epitopes were linked to a single pH Low Insertion Peptide peptide two Peg12 or Peg24 polymers, which enable HA epitopes to engage both antibody binding sites. HA-epitopes positioned at the surfaces of tumor cells remain exposed to the extracellular space for 24-48 h and are then internalized. Different vaccination schemes and various adjuvants, including analogs of FDA approved adjuvants, were tested in mice and resulted in a high titer of anti-HA antibodies. Anti-HA antibody binds HA-pHLIP in blood and travels as a complex leading to significant tumor targeting with no accumulation in organs and to hepatic clearance. HA-pHLIP agents induced regression of 4T1 triple negative breast tumor and B16F10 MHC-I negative melanoma tumors in immunized mice. The therapeutic efficacy potentially is limited by the drop of the level of anti-HA antibodies in the blood to background level after three injections of HA-pHLIP. We hypothesize that additional boosts would be required to keep a high titer of anti-HA antibodies to enhance efficacy. pH Low Insertion Peptide-targeted antigen therapy may provide an opportunity to treat tumors unresponsive to T cell based therapies, having a small number of neo-antigens, or deficient in MHC-I presentation at the surfaces of cancer cells either alone or in combination with other approaches.
Cetuximab therapy has been effectively combined with cytotoxic chemotherapy in the first-, second-, and third-line treatment settings. In general, treatment with cetuximab is well tolerated, though it has been associated with the development of hypersensitivity reactions (HSRs). In the case of severe HSRs, further therapy with cetuximab is not possible. In contrast with cetuximab, HSRs have been rarely observed with panitumumab therapy. Currently, panitumumab is indicated for patients with metastatic colorectal cancer (mCRC) with progressive refractory disease, and there is recent evidence documenting its clinical efficacy with cytotoxic chemotherapy in the first-line and second-line settings. However, the safety and efficacy of panitumumab after progression with cetuximab has not been well documented. We present a retrospective review of our experience in treating 15 patients with mCRC who tolerated panitumumab with clinical benefit after failure on cetuximab therapy from November 2006 through September 2008 at the Yale Cancer Center in New Haven, CT and at the Saint Francis Cancer Treatment Center in Grand Island, NE. KRAS status was retrospectively assessed in patients with readily available tumor tissue. All 15 patients were treated with a standard dose of panitumumab 6 mg/kg intravenously every 2 weeks. No patient received premedication therapy. Of the 15 patients treated, 4 received only 2 doses of panitumumab but stopped further therapy because of deterioration in performance status. Of the 11 evaluable patients, we noted minor radiographic responses (Response Evaluation Criteria in Solid Tumors) in 3 patients and stable disease (SD) in 3 other patients after 8 weeks of therapy. Five patients had evidence for progressive disease, and further therapy was stopped. The median duration of SD was 4 months (range, 2-8 months). Among the 11 evaluable patients, 1 patient achieved > 50% reduction in carcinoembryonic antigen (CEA; 112 to 49 U/L), 3 patients had a 25% reduction (59 to 43 U/L, 84 to 61 U/L, and 67 to 42 U/L), and 1 patient had minor reduction in CEA (98 to 83 U/L). All patients tolerated panitumumab well with no occurrence of hypersensitivity reactions. Grade 3/4 toxicities were skin rash in 5 patients and asthenia in 1 patient. The other adverse events observed included grade 1-2 skin rash in 2 patients, grade 2 paronychia in 4 patients, grade 2 hypomagnesemia in 2 patients, and fatigue in 3 patients. One patient had wild-type KRAS, and this individual experienced a minor response to antibody therapy with > 50% reduction in CEA. A second patient was found to have mutant KRAS and, in terms of clinical response, this patient experienced SD for 6 months. The third patient evaluated had mutant KRAS, and this individual was unable to tolerate more than 2 doses and was therefore not evaluable for response. Panitumumab may represent an alternative treatment strategy for patients with refractory mCRC who have experienced failure with standard therapy including cetuximab-based regimens. Our relatively small clinical experience suggests that cetuximab and panitumumab may exert their antitumor activity through different mechanisms; however, further work is required to investigate this potentially interesting issue.
Monoclonal antibodies (MAbs) targeting epidermal growth factor receptor (EGFR) are effective in treatment of metastatic colorectal cancer (mCRC). Cetuximab, a chimeric MAb targets EGFR. Even with premedication, cetuximab can cause a hypersensitivity reaction (HSR). In case of severe HSR, further therapy with cetuximab is contraindicated, thus preventing these patients from receiving potentially beneficial anti-EGFR therapy. Panitumumab is a fully human MAb also targets EGFR. To date, no human antihuman Ab have been detected, and unlike CET, HSR are infrequent, and no premedication is required. Safety of panitumumab in patients with a previous severe HSR with cetuximab is not fully known. We present three patients with GI cancers who tolerated panitumumab without HSR after experiencing severe HSR to cetuximab. Three patients were challenged with standard dose of panitumumab (6 mg/kg) after experiencing grade 3 HSR to standard dose of cetuximab under strict observation and no premedication. First patient, a 58-year-old male with mCRC developed grade 3 HSR during 8th dose of cetuximab. Second patient was a 58-year-old female with mCRC developed grade 3 HSR during 12th dose of cetuximab. Third patient was a 61-year-old male with pancreatic cancer who experienced grade 3 HSR during loading dose of cetuximab. Charts were reviewed to find history of prior allergy, including H1 blocker use, drug allergy, bee sting allergy, eczema, allergic reactive airways disease, or food allergy. All patients were Caucasians with an average age of 59 year with no history of prior allergy. No patient received any premedication. First patient received panitumumab for 2 months, second patient was treated for 6 months, and third patient who was rechallenged 1 week after HSR to cetuximab had a partial response following 6 months of therapy. HSR are serious complications associated with MAbs. Thanks to hybridoma technology that newer generations of MAbs contain less or no mouse-specific protein sequences, hence reducing the risk of HSR. Identification of individuals likely to develop severe and sometimes life-threatening HSR is challenging. Our report of three patients successfully treated with panitumumab after they had severe HSR to cetuximab warrant further investigation.
Saif MW, Syrigos KI, Hotchkiss S, Shanley J, Grasso J, et al.
Cancer chemotherapy and pharmacology •
Cetuximab and panitumumab are chimeric and fully human monoclonal antibodies, respectively, against epidermal growth factor receptor used in the treatment of metastatic colorectal cancer (mCRC). Incidence of documented infusion reaction (IR) is more common with cetuximab (all grades [g]: 15-21%, g 3/4: 2-5%) than panitumumab (all g: 4%, g 3/4: 1%). Anecdotal reports suggest successful challenge with panitumumab following IR with cetuximab (Saif et al. in Cancer Chemother Pharmacol 63(6):1017-1022, 2009). However, safety of cetuximab after IR with panitumumab is not known. We report two patients successfully desensitized with cetuximab after IR with panitumumab. A 42-year-old female with mCRC received panitumumab as a third-line agent. She developed severe chest tightness, pain, and shortness of breath (SOB), 5 min after first panitumumab infusion. A second 70-year-old male with mCRC developed severe facial flushing, back pain, SOB, tachycardia and hypotension, 5 min after second dose of panitumumab plus irinotecan as a second-line therapy. These two patients received desensitization protocol for cetuximab after a test dose of 20 mg IV over 10 min followed by a slow infusion 10% of original rate in 0-2 h, 25% of original rate in 2-2.5 h, 50% reduced rate in 2.5-3 h, and then 100% infusion rate after 3 h. Patients were observed 4 h after completion of infusion. First patient received a total of 12 cycles of cetuximab with stable disease, no recurrence of IR, and grade 1-2 acniform rash that first developed after third cycle. Second patient received a total of eight cycles uneventfully without IR. To our knowledge, this is the first report of two patients with documented IR with panitumumab being desensitized successfully with cetuximab. Though anecdotal reports suggest safety of panitumumab in patients following IR with cetuximab, panitumumab can also cause severe IR. Our experience suggests that in case of limited options, such patients can be successfully challenged with cetuximab in a hospital after appropriate desensitization and premedication. Further studies focusing on desensitization and identifying hypersensitivity profile of different anti-epidermal growth factor receptor antibodies are warranted.
Germline mutations in the tumor suppressor genes BRCA1 and BRCA2 have been proven to predict a drastically increased lifetime risk of breast and ovarian cancers in the individuals who carry them. A number of studies have shown that the third most common cancer associated with these mutations is pancreatic cancer. There is evidence of in vivo therapeutic response to the cross-linking agents; such as mitomycin C (MMC) in BRCA2 mutated pancreatic cell lines. We present the 'first patient' who achieved a prolonged survival on irinotecan, a topoisomerase I poison, administered alone and then in combination with cetuximab. Our patient presented at the age of 71 years with a dual diagnosis of prostate carcinoma and pancreatic carcinoma on the background of a significant family history of cancer. On genetic testing, he was found to have the common Ashkenazi Jewish BRCA2 mutation, 6174delT. To date, he has received 22 cycles of docetaxel, capecitabine, and gemcitibine followed by single agent irinotecan every 3 weeks for 27 cycles, and then weekly cetuximab was added to the regimen at cycle 28. His disease then remained stable for an additional 13 months. He did not have mutated KRAS. MMC and oxaliplatin was then introduced upon progression. His current treatment is MMC plus irinotecan as oxaliplatin was removed because of a hypersensitivity reaction. This patient is stable with an Eastern Cooperative Oncology Group performance status of 0, four and a half years (56 months) after his initial diagnosis. DNA topoisomerases are nuclear enzymes responsible for the regulation of DNA topology. They are involved in basic DNA transactions during replication, transcription, and recombination. BRCA2-deficient human cells are deficient in the repair of double-strand breaks and DNA cross-links through homologous recombination. Active poisons of topoisomerase I include derivatives of camptothecin. Our case is the first clinical piece of evidence that demonstrates an increased sensitivity to camptothecin-11 and a reduced topoisomerase I relaxation activity in BRCA2 associated pancreatic cancer. This case shows that patients with metastatic pancreatic carcinoma and BRCA2 mutations may have disease that is biologically more chemosensitive and consequently prolong survival despite prognostically unfavorable disease.
Cetuximab is a human/mouse chimeric monoclonal antibody that binds to the EGF receptor, competitively inhibiting ligand binding, and inducing receptor dimerization and downregulation. Cetuximab has been active in multiple tumors, including colorectal cancer (CRC), head and neck, pancreatic and lung cancers. Cetuximab has been approved by the FDA, in combination with irinotecan, for the treatment of metastatic CRC in patients refractory to irinotecan, and for use as a single agent in the treatment of recurrent metastatic CRC in patients intolerant of irinotecan-based chemotherapy. Most common toxicities are rash, diarrhea, fever, headache, nausea, hypomagnesemia and hypersensitivity reactions. Data from several clinical trials with cetuximab show a positive correlation between rash and response and/or survival. Rash occurred on 90% of patients treated with cetuximab monotherapy and grade 3 or 4 skin reactions occurred on as many as 16% of patients in the trials using cetuximab. A rash usually presents as pustular or maculopapular follicular eruption, often referred to as acneiform. Cetuximab will engage in productive dimerization complexes in human skin causing significant disruption of the normal development and maintenance of the hair follicle, which leads to follicular response and inflammatory response. At this time there are no standard or evidence-based treatment plans for the rash. Most of the evidence is based on institutional or personal experiences. The most commonly used agents are topical antibiotics, oral antibiotics, topical steroids, systemic immunomodulatory agents, topical immunomodulatory agents and anti-inflammatory preparations. As cetuximab is becoming widely used in general oncology practice, it is important to understand the toxicity of rash to develop practice guidelines for their management. This review addresses recommendations for toxicity management of rash caused by cetuximab in treatment of metatstatic CRC.
Many retroviral vectors for hematopoietic cell and other clinical gene therapy are derived from murine packaging cell lines. The exposure of these retroviruses and packaging cell lines to adult human serum (AS) inactivates them by complement and anti-alpha-galactosyl natural antibody-mediated mechanisms. We show that virus stability and infection efficiency of CRIP/BAG, a murine packaging cell line derived amphotropic retrovirus vector is reduced > 95% following a 30-min incubation in AS. This inactivation is prevented by replacing AS with umbilical cord serum (CS), wherein full retroviral transduction efficiency is maintained after 30 min of incubation. The loss of retrovirus transduction efficiency in AS was smaller upon blockage of anti-alpha-galactosyl antibodies with galactose alpha 1-3-galactose. Serum levels of CH 100, as well as C1q complement which inactivates retroviruses by an antibody-independent mechanism were similar in AS and CS. The high stability of CRIP/BAG retrovirus vector in CS is likely due to its lower levels of maternally derived anti-alpha-galactosyl antibodies. These results have implications for in vivo gene transfer in adults and also in newborns since neonates do not produce natural antibodies during the initial months of life.
Ariga T, Yu RK, Scarsdale JN, Suzuki M, Kuroda Y, et al.
Biochemistry •
In a previous paper, we reported the presence of globoside as a major neutral glycolipid in PC12 pheochromocytoma cells [Ariga, T., Macala, L. J., Saito, M., Margolis, R. K., Greene, L. A., Margolis, R. U., & Yu, R. K. (1988) Biochemistry 27, 52-58]. Recently, we found that subcloned PC12h cells accumulated another unusual neutral glycolipid. In order to characterize this glycolipid, PC12h cells were subcutaneously transplanted into rats. The induced tumor tissue accumulated two major neutral glycolipids, which were purified by Iatrobeads column and preparative thin-layer chromatographies. One of the glycolipids was found to be globoside, and the other had a globotriaosyl structure with an additional terminal Gal alpha 1-3 residue. Its structure was determined by fast atom bombardment mass spectrometry, two-dimensional proton nuclear magnetic resonance spectrometry (2D NMR), permethylation study, sequential degradation with exoglycosidase, and mild acid hydrolysis to be Gal(alpha 1-3)Gal(alpha 1-4)Gal(beta 1-4)Glc(beta 1-1')Cer.
