Protective activity of specific transfer factor against Salmonella typhimurium infection

Specific transfer factor (TF) extracted from spleens of sensitized and non-sensitized guinea pigs to study the efficacy of transfer of cellular immunity specific for salmonella . Two groups each of five guinea pigs were used for in vivo TF preparation. The First group was inoculated with 1 ml of aromatic dependent Salmonella typhimurium SL 1479 vaccine at a dose of 10' cfu/ml intramuscularly twice at two weeks intervals. The second group was injected with trypticase soy broth similarly . These two groups used as a donor for TF, and TFn respectively. Twenty one recipient guinea pigs were divided into three groups, the first group was TF at a dose of 1 ml equivalent to 5X10 cell intramuscularly three times/2 days intervals, Similarly the second group was given TF, where as the third group was given PBS- Cell mediated immunity in recipient animal was evaluated by delayed type hypersensitivity - skin test, Macrophage migration inhibition test (MIF) and then challenged with virulent Salmonella typhimurium. The TFt recipient group induced skin test and showed migration indices less than 0.8 and overcome the challenge organism. Contrary to TFn & PBS recipient groups which did not show any response for skin test and given migration indices more than 0.8 and did not show resistance for virulent Salmonella typhimurium .

The Beauty of Simplicity: Delayed-Type Hypersensitivity Reaction to Measure Cellular Immune Responses in RNA-SARS-Cov-2 Vaccinated Individuals

Background: Monitoring cellular immune responses elicited in vaccinated individuals is highly complicated. Methods: 28 individuals participated during the vaccination process with 12 BNT162b2 mRNA (Pfizer) vaccine. Specific anti-RBD IgG using a classic ELISA was performed in days 10 and 20 (after one dose of the vaccine) and on day 35 (after two vaccine doses) in serum samples of all participants. In parallel, DTH (delayed-type hypersensitivity) Skin Test using S protein was performed before (11/28) and after two doses (28/28) of the vaccine. Results: 6/28 individuals were considered positive for the specific anti-RBD IgG positive at day 10, whereas all 28 individuals were positive at day 20. Moreover, 28/28 individuals increased the OD ratios at day 36 (2 doses). DTH cutaneous test was performed on 11/28 participants at day 20 (1 dose) showing 8/11 a positive reaction at 12 h. DTH of all participants was performed on day 36 (2 doses), showing 28/28 positive reactions at 12 h. Conclusion: This report describes the first publication of the results obtained using an in vivo method, the classical DTH response to the Spike protein to assess T-cell immune responses in vaccinated individuals. This affordable and simple test would help to answer basic immunogenicity questions on large-scale population vaccine studies.

Anaphylaxis After the Covid-19 Vaccine in a Patient With Cholinergic Urticaria

ABSTRACT Cholinergic urticaria is a common disorder that has been associated with anaphylaxis. We report the events, workup, and eventual second dose vaccination of a patient at the Walter Reed National Military Medical Center, who had immediate anaphylaxis after administration of the first Pfizer-BioNTech Covid-19 (BNT162b2) vaccine dose. During the initial evaluation after anaphylaxis, the patient described a history of symptoms suspicious for cholinergic urticaria but had never had this condition confirmed with standardized testing. After the episode of anaphylaxis, we performed several studies including immediate hypersensitivity skin testing, which did not demonstrate vaccine or component sensitization. We then performed an exercise provocation challenge and confirmed the diagnosis of cholinergic urticaria. These results, combined with the patient history, suggested that the episode of anaphylaxis was most likely driven by a severe flare of cholinergic urticaria. After obtaining the patient’s consent, she received and tolerated her second dose without any objective findings of anaphylaxis. We conclude that patients with mast cell disorders or anaphylaxis after their first Covid-19 immunization will benefit from referral to an allergist since receipt of their second Covid-19 immunization may be possible.

Case Report: Successful use of fondaparinux in a case of heparin intolerance during pregnancy

Heparin is the anticoagulant of choice during pregnancy. However, in cases of intolerance or adverse effects, another anti-coagulant agent should be administered. Here, we describe a case of hypersensitivity skin reaction seen in a 37-year-old pregnant patient at 11 weeks of gestation who used low-molecular-weight heparin (LMWH). Fondaparinux was used as an alternative during her pregnancy with a successful outcome.