B lymphocytes are compartmentalized within lymphoid organs. The organization of these compartments depends upon signaling initiated by G-protein linked chemoattractant receptors. To address the importance of the G-proteins Gαi2 and Gαi3 in chemoattractant signaling we created mice lacking both proteins in their B lymphocytes. While bone marrow B cell development and egress is grossly intact; mucosal sites, splenic marginal zones, and lymph nodes essentially lack B cells. There is a partial block in splenic follicular B cell development and a 50-60% reduction in splenic B cells, yet normal numbers of splenic T cells. The absence of Gαi2 and Gαi3 in B cells profoundly disturbs the architecture of lymphoid organs with loss of B cell compartments in the spleen, thymus, lymph nodes, and gastrointestinal tract. This results in a severe disruption of B cell function and a hyper-IgM like syndrome. Beyond the pro-B cell stage, B cells are refractory to chemokine stimulation, and splenic B cells are poorly responsive to antigen receptor engagement. Gαi2 and Gαi3 are therefore critical for B cell chemoattractant receptor signaling and for normal B cell function. These mice provide a worst case scenario of the consequences of losing chemoattractant receptor signaling in B cells.

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Introduction: Varicella zoster virus (VZV) meningitis is primarily an infection of the immuno-compromised. However, it can also affect immunocompetent individuals. Reactivation of VZV typically presents with a distinct dermatomal rash suggestive of varicella zoster, but there have also been reports of VZV meningitis presenting without a rash. Case Report: We describe a case of VZV meningitis in a healthy, 30-year-old male presenting to the emergency department shortly after receiving his first coronavirus disease 2019 vaccination. He was treated with intravenous acyclovir and then discharged home on oral valacyclovir. Conclusion: Emergency physicians should consider aseptic meningitis in immunocompetent patients presenting with atypical headaches in this population.

Case presentation: A 33-year-old male presented to the emergency department following a motor vehicle collision with complaints of right eye pain after hitting his head on the steering wheel. Point-of-care ultrasound (POCUS) revealed retinal detachment and an anterior lens dislocation. Discussion: Lens dislocations following blunt head trauma can often be diagnosed using POCUS. Anterior ocular lens dislocation is a rare but vision-threatening result of head trauma. This case highlights how POCUS can facilitate early detection of ocular pathology, such as lens dislocation, and improves patient outcomes.